Million Solar Roofs Bill Signed into Law
H. E. Taylor
After a long roller-coaster ride in the California legislature, the Million
Solar Roofs Bill, SB1, is now law. Governor Schwarzenegger, who campaigned
on a pledge to create a major solar program, signed the bill Monday. The
bill, authored by Senator Kevin Murray, went through an evolution of
different versions over the past three years leading to collective moments
of both euphoria and disappointment for the solar industry. This final
version proved suitable enough to California lawmakers and the competing
special interests with a stake in its outcome.
[...]
<http://www.renewableenergyaccess.com/rea/news/story?id=45786>
See also:
2006/08/22: SOSD: Bill signing completes governor's [million solar roofs] plan -
More panels, cleaner power goal of project
<http://www.signonsandiego.com/news/state/20060822-9999-1n22solar.html>
2006/08/22: TLC: California Leads the Way in Solar Power
<http://www.theleftcoaster.com/archives/008537.php>
--
"Ignorance, allied with power, is the most ferocious enemy
justice can have." -James Baldwin
Energy Alternatives: http://www.autobahn.mb.ca/~het/energy/energy.html
H.E. Taylor http://www.autobahn.mb.ca/~het/
Eeyore
"H. E. Taylor" wrote:
> 2006/08/23: REA: Million Solar Roofs Bill Signed into Law
>
> After a long roller-coaster ride in the California legislature, the Million
> Solar Roofs Bill, SB1, is now law. Governor Schwarzenegger, who campaigned
> on a pledge to create a major solar program, signed the bill Monday. The
> bill, authored by Senator Kevin Murray, went through an evolution of
> different versions over the past three years leading to collective moments
> of both euphoria and disappointment for the solar industry. This final
> version proved suitable enough to California lawmakers and the competing
> special interests with a stake in its outcome.
> [...]
> <http://www.renewableenergyaccess.com/rea/news/story?id=45786>
>
> See also:
> 2006/08/22: SOSD: Bill signing completes governor's [million solar roofs] plan -
> More panels, cleaner power goal of project
> <http://www.signonsandiego.com/news/state/20060822-9999-1n22solar.html>
I just read this. Is this PV solar ? Sounds like it.
It depends on 1 million homes each generating an average 3kW throughout the 24 hr
day !
Are they joking ?
Graham
Alex Terrell
That's a pretty big solar array - so it seems to me the numbers don't
add up.
Still, if you've got a 3KW array, you can keep your air conditioning
running when there's one of the regualr power blackouts.
mike...@yahoo.com
Well with 3KW you can still run some stuff. It's better than a total
blackout, and
this way the homes can contribute power to the grid instead of just
sucking it
up.
Mel
financing grid connected PV, and requiring utilities to develope solar
rebate programmes
I think it's great news; in heavy air conditioning using areas, such as
California, peak summer daytime loads and hence strain on th local grid
can be reduced.
Alex and Mike:
Grid connected means no grid, no solar production. If you want grid
backup we're talking about back up systems; it's not quite the same thing.
And 3kWp to low to be useful? Are you kidding? A 3kWp system should be
producing well over 3000kWh/year in California, that's more than half
what an intelligent electricity consummer family should be consuming.
Mel
Alex Terrell a écrit :
Matthew Beasley
>"Mel" <mel...@pasdespam.chezmoi> wrote in message
>news:44ed78e7$0$10964$636a...@news.free.fr...
>And 3kWp to low to be useful? Are you kidding? A 3kWp system should be
>producing well over 3000kWh/year in California, that's more than half what
>an intelligent electricity consummer family should be consuming.
3MWh? I'm using 1/3 of that during shoulder months, but that's one month
usage for me in the worst of summer or winter. I didn't think I was that
wasteful. Well insulated house, compact flourescents for most used lights,
programmable thermostat, etc...
do...@xrexxmilli.usenet.us.com
<rabbitsfriend...@removethis.hotmail.com> wrote:
> I just read this. Is this PV solar ? Sounds like it.
> It depends on 1 million homes each generating an average 3kW throughout
> the 24 hr day !
I didn't see kWh, or per day, or annual yield.
I see "3,000 megawatts" If we divide that by the title of the project, 1
million roofs, that's a 3KW system.
Further down, it says that the "typical house, about $15,000", so that is
in line with the 3KW system.
I would think that should be the average sized system. With the net
metering plans, you don't want to generate all of your own energy.
3KW would be beyond the needs pf many people.
--
---
Clarence A Dold - Hidden Valley Lake, CA, USA GPS: 38.8,-122.5
Eeyore
do...@XReXXMilli.usenet.us.com wrote:
> In alt.solar.photovoltaic Eeyore
> <rabbitsfriend...@removethis.hotmail.com> wrote:
>
> > I just read this. Is this PV solar ? Sounds like it.
>
> > It depends on 1 million homes each generating an average 3kW throughout
> > the 24 hr day !
>
> I didn't see kWh, or per day, or annual yield.
>
> I see "3,000 megawatts" If we divide that by the title of the project, 1
> million roofs, that's a 3KW system.
Exactly. 3kW. As I said.
> Further down, it says that the "typical house, about $15,000", so that is
> in line with the 3KW system.
PV ? No way. $15,000 would give you about 1000W for maybe 7 hours a day ?
> I would think that should be the average sized system. With the net
> metering plans, you don't want to generate all of your own energy.
> 3KW would be beyond the needs pf many people.
Really ?
Graham
Eeyore
mike...@yahoo.com wrote:
PV only makes electricity when the sun's shining. To produce an average of 3kW you'de
need say 9kW worth of panels, say 900 sq ft !
Graham
do...@xrexxmilli.usenet.us.com
> And 3kWp to low to be useful? Are you kidding? A 3kWp system should be
> producing well over 3000kWh/year in California, that's more than half
> what an intelligent electricity consummer family should be consuming.
My system lagged behind the A/C demand for the last couple of months, which
was abnormally high, but it is doing well for me this year. It has
displaced $1,046.63 in PG&E billing. My 3.8KW array has produced 4190KWH,
60% of my usage.
http://cdold.home.mchsi.com/Solar-generation.htm
do...@xrexxmilli.usenet.us.com
> They mean 3GW of capacity, which is 3KW each peak, which is about 30m2.
My array is 3.8KW, 33m2, 52'x7'.
http://cdold.home.mchsi.com/Solar-generation.htm
> That's a pretty big solar array - so it seems to me the numbers don't
> add up.
The numbers look right. Whether that's too big is in the eye of the
beholder. Mine is roof mount. My neighbor's is ground mount.
Jim has a 10 kw system that is larger than his roof.
http://www.baber.org/
> Still, if you've got a 3KW array, you can keep your air conditioning
> running when there's one of the regualr power blackouts.
The "$15,000 system" that the article mentions would not have battery
backup. When the power goes out, the grid-tie PV inverter shuts down.
Dan Bloomquist
do...@XReXXMilli.usenet.us.com wrote:
> In alt.solar.photovoltaic Mel <mel...@pasdespam.chezmoi> wrote:
>
>>And 3kWp to low to be useful? Are you kidding? A 3kWp system should be
>>producing well over 3000kWh/year in California, that's more than half
>>what an intelligent electricity consummer family should be consuming.
>
>
> My system lagged behind the A/C demand for the last couple of months, which
> was abnormally high, but it is doing well for me this year. It has
> displaced $1,046.63 in PG&E billing. My 3.8KW array has produced 4190KWH,
> 60% of my usage.
>
> http://cdold.home.mchsi.com/Solar-generation.htm
Hay, that makes you a neighbor of Haverty. Does he still own Lakeside TV
& Appliance?
Best, Dan.
Eeyore
do...@XReXXMilli.usenet.us.com wrote:
> In alt.solar.photovoltaic Alex Terrell <alext...@yahoo.com> wrote:
>
> > They mean 3GW of capacity, which is 3KW each peak, which is about 30m2.
>
> My array is 3.8KW, 33m2, 52'x7'.
> http://cdold.home.mchsi.com/Solar-generation.htm
>
> > That's a pretty big solar array - so it seems to me the numbers don't
> > add up.
>
> The numbers look right. Whether that's too big is in the eye of the
> beholder. Mine is roof mount. My neighbor's is ground mount.
>
> Jim has a 10 kw system that is larger than his roof.
Hardly surprising for 10kW. To generate 10kW year round would take ~ 10,000 sq
ft !
Graham
do...@xrexxmilli.usenet.us.com
<rabbitsfriend...@removethis.hotmail.com> wrote:
> PV only makes electricity when the sun's shining. To produce an average
> of 3kW you'de need say 9kW worth of panels, say 900 sq ft !
A system in California is sold based on a "CEC Rated kilowatt Output".
All systems should be rated to some standard insolation.
http://rredc.nrel.gov/solar/codes_algs/PVWATTS//system.html
What you are suggesting is that a set of 10 panels installed in Mexico
should be called "10k worth" and the same set of panels installed
in England should be called "2k worth", because of the different average
output.
Eeyore
do...@XReXXMilli.usenet.us.com wrote:
> In alt.solar.photovoltaic Eeyore
> <rabbitsfriend...@removethis.hotmail.com> wrote:
>
> > PV only makes electricity when the sun's shining. To produce an average
> > of 3kW you'de need say 9kW worth of panels, say 900 sq ft !
>
> A system in California is sold based on a "CEC Rated kilowatt Output".
>
> All systems should be rated to some standard insolation.
> http://rredc.nrel.gov/solar/codes_algs/PVWATTS//system.html
>
> What you are suggesting is that a set of 10 panels installed in Mexico
> should be called "10k worth" and the same set of panels installed
> in England should be called "2k worth", because of the different average
> output.
Of course, because that's the real output.
The PV world is full of lies and obfuscation.
Since the sun doesn't shine 24 hrs a day at full mid-day brightness those
figures should be further derated by a factor of at least 4 times.
Graham
John Ladasky
interest here.
Rather than respond to any one person specifically, I'll make a general
response. I'm a Californian, and the owner of a grid-tied residential
PV system.
Some people have questioned whether a million solar-equipped roofs is
feasible for California, or whether we could really produce 3.0
gigawatts with those million roofs, if they existed. My answer to both
questions is a qualified yes.
First of all, there's already quite a bit of solar power generated in
California, though most of it is not generated on residential land.
There are about 30,000 homes in California today with solar PV
installations, but most solar is generated in commercial and industrial
settings. In 2004, the total output from all solar power systems in the
state was 741 gigawatt-hours over the course of the year. This was
0.3% of the state's total electrical use.
http://www.energy.ca.gov/electricity/gross_system_power.html
For a residential example, let's look at my system. I have 27 BP3160
PV modules on my second-story roof, above all nearby trees and
obstructions. The system's theoretical maximum output, after the
inverters, is 4.1 kW. In practice, in direct sunshine I peak at 3.5
kW. There's a magical moment which occurs when the sun is framed by
thin clouds. Then, when I receive both direct sunlight and scattered
sunlight, my system jumps all the way up to the 4.0 kW range.
Now, there's a LOT of direct sunshine here in California. In its first
12 months of operation, my system generated 6497 kWh. Over the same
time period our house used 6967 kWh, so we generated 93% of what we
used at the house. We are a family of three.
We have an ordinary suburban home, with only a few upgrades --
compact-fluorescent lights and Energy Star appliances. I still have to
upgrade a few halogen-lamp torchieres (yuck!). We do dry a few loads
of laundry outside when the weather is good. And we don't have any
air-conditioning -- most homes within about 30 miles of the California
coast can get by without it. I may add geo-exchange heating/cooling in
the next year or two.
Mostly, what my family does is to care about turning off lights and
televisions when we leave a room. Now, for those of you who say that
you need more power -- well, MAYBE you do. Maybe you live in a place
which requires air conditioning. When we lived in Baltimore, Maryland,
we used our AC. In one particularly bad month we used a whole 900 kWh,
just for the AC.
Then again, you could be a Real American. I sure hope you aren't one
of those. I had one as a tenant for a while, and I shared his utility
bill. Big mistake. His story is here:
http://groups.google.com/group/alt.global-warming/msg/89aac384f31542e0
Some people have questioned whether a household PV system which
generates 3.0 kW peak (one million of which would generate the 3.0 GW
mentioned in the initiative) would cover any meaningful amount of load.
The answer to this question is definitely yes. On the absolute worst
days here in California, demand peaks in the mid-afternoon, at about 51
GW. Which days are these? Hot, cloudless days when everyone turns on
their air conditioning. You can learn more than you would ever want to
know about energy use in California from the Independent System
Operators' web page:
http://caiso.com/outlook/SystemStatus.html
Well, the times of peak electrical demand are, conveniently, the same
times when PV will perform at its best. Now, my PV system is actually
oriented towards the southwest rather than due south. So I am actually
generating my peak power at around 3:00 PM, not at noon. And I get
rewarded for this. California encourages (and may soon mandate?) the
installation of time-of-use meters. Electricity costs more on summer
days between 1 and 7 PM. On the other hand, surplus electricity
generated during those peak hours is worth more to me.
It may be a bit optimistic to assume that the next million PV systems
will all be oriented southwest, like mine. But, to a first
approximation, we will have added about 3 GW of headroom at our
afternoon peak power use of 51 GW. That's a 6% added safety margin
against power failures. A million roofs like mine would generate about
6000 GWh over the course of one year. That's not quite a ten-fold
increase from the 741GWh we generate using solar today.
By the way, there are about 6.8 million single-family dwellings in
California right now, so a million roofs represents only 14% of our
present total.
We might also include multi-unit dwellings in this effort.
The only problem that I see with achieving 3 kW per residential rooftop
is that not everyone's roof is as easy to use as mine. Our home was
built around 1970 and has a simple, peaked roof with two leaves. My PV
array occupies 34 square meters (367 square feet), and it's in a single
piece. Two sets of stringers support all of the PV modules. The
installation was simple and tidy.
Today's home-builders are enamored with frou-frou, "Tuscan" roofs with
lots of angle changes over short distances. These designs should be
outlawed immediately. Otherwise we'll get a million new roofs out
here, with no place to install solar! Hip roofs also decrease PV
installation space, though not as much as the pointless decorative
angle changes.
Finally, some people considered the value of adding solar PV to keep a
residence powered when the grid fails. California does not compensate
homeowners for any off-grid capabilities, and the Million Solar Roofs
Initiative will not change that. You need special "islanding"
inverters which can manage a battery bank and generate their own 60 Hz
AC in order to stay "up" when the grid goes down. If you want that
capability, you have to pay for it yourself. (And in the long run,
because you have to replace batteries, adding off-grid capability will
cost more than the rest of your system.) Having said that, your
grid-tied PV system supports the grid as a whole, and makes it less
likely that your power will fail.
I would like to see California's Million Solar Roofs Initiative copied
across every state in the Sun Belt (fat chance in Texas or Louisiana, I
know). Then, I would like to see a Ten Million Electric Vehicle
Passenger-Miles Per Day Inititative!
+-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-+
| Ladasky Home Solar, Inc.: blowing sunshine up your |
| power grid since March 24, 2005. Fiat lux! |
+-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-+
| Uptime Downtime kWh generated kWh consumed |
| 513 days 6.5 hours 9756 9718 |
+-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-+
Mel
>
snip
>
> Of course, because that's the real output.
>
> The PV world is full of lies and obfuscation.
>
> Since the sun doesn't shine 24 hrs a day at full mid-day brightness those
> figures should be further derated by a factor of at least 4 times.
>
> Graham
>
That is why the PV industry uses kWp (kiloWatt peak) and not kW
(kioWatt); it tells how much power in certain standard optimised
conditions the module can give out.
Could you imagine selling pv modules over the internet and using a power
rating that is based on a geographical location? Which geographical
location do you choose? And if you're buying for New York but the seller
has put up the Dubai rating, how's that going to help you? You'de have
to go through the conversion process anyway.
Be thankful that the industry got itselg together to define a kWp,
otherwise it would be a lot harder to know what exactly you were buying.
Mel
steve
tangent about "do numbers add up".
i followed the million solar roofs bill from the start. thru the
process i decided to get my own solar electric system. for me, in the
summer on a typical day, i produce by solar electric 120% to 140% of
what i use on a daily basis. with a passive solar home i don't have to
run AC much. my summer bills are near $0. ($1.99 is actually the
smallest bill we can get because we still pay for the grid wires).
what a "million solar roofs" means new home developments will be
desinged with solar adaption in mind - setting aside 10% of new homes
as "solar ready". you pick out the tile of your kitchen, the carpet,
and oh by the way solar electric. in time if/when solar is designed
into homes up front on a steady basis, the systems will become more
common. the costs - which i feel are already not bad - can be spread
over a 30 year loan & be very small for homeowners.
as seen with my own home, i ADD power to the grid during the day. with
1 million solar roofs ADDING to the grid a day that is the same as
adding up to 6 regular power plants to the grid.
adding - dispersing - solar roofs into the grid is using the existing
grid distribution & existing land. no one needs to buy land for new
power plants nor staff these plants as is currently done. and the
power is very oil independent.
now imagine the concept growing to where 20% of the homes are using
solar? that would be like dropping 20% of the homes OFF the grid
during the day while they add still another 40% ONTO the grid much like
my own system does each summer day.
not all states can do this because of weather issues. but the
southwest certainly should take california's lead & do something
similar.
see ya
steve
axol...@hotmail.com
installed about 14GW total in 2005; how's this going to affect the
availability and price of panels?
SJC
<axol...@hotmail.com> wrote in message news:1156610377.2...@i42g2000cwa.googlegroups.com...
> Wouldn't 3GW peak require about 15 million 200 watt panels? The world
> installed about 14GW total in 2005; how's this going to affect the
> availability and price of panels?
>
the panels that they can get, the prices will stay high and a million roofs may
take quite some time.
R.H. Allen
I think you dropped a decimal point -- worldwide installations in 2005
were more like 1.4 GW (with 1.7 GW shipped).
The only way the new policy can affect availability right now is to
lengthen waiting time for product, as most manufacturers have already
sold all of their short-term future production (6-18 months worth for
most companies). I doubt it will affect the price much, though, since
California's program is a buy-down subsidy. Under such programs, I
believe demand drops off quite sharply if prices exceed a certain level.
John Ladasky
For decades, the solar PV industry was able to buy silicon wafers which
were rejected by the semiconductor industry. About two years ago, that
changed. For the first time, the PV industry needed more silicon than
it could buy from the reject pile.
The residential PV system on my house was installed in three days last
March -- but we waited over three months for the modules!
Historically, demand for PV has varied widely even as the general trend
has been positive. Government incentives for PV come and go quickly,
as politicians maneuver for position with their constituencies. This
uncertainty has discouraged PV manufacturers and manufacturers of
silicon ingots from committing to long-term contracts.
I think that the Million Solar Roofs Initiative sends a signal to the
PV industry. They can count on customers for their product, so it's
safe to expand production. And there is some spare manufacturing
capacity. For example, I know that companies like Evergreen Solar
wanted to make more PV modules this year, but couldn't, due to supply
problems.
By next year, I would expect to see an increase in long-term contracts
between the silicon suppliers and the PV manufacturers. The supply of
finished product should be more steady, and prices shouldn't change by
much.
Lastly, California's initiative does not specify that all 3 GW of PV
will be installed in a single year. I think the target date is ten
years from now. At 0.30 GW/year, it won't be a huge jump in demand
when compared to the 14 GW which were installed last year -- just 2
percent.
John Ladasky
> axol...@hotmail.com wrote:
> > Wouldn't 3GW peak require about 15 million 200 watt panels? The world
> > installed about 14GW total in 2005; how's this going to affect the
> > availability and price of panels?
>
> I think you dropped a decimal point -- worldwide installations in 2005
> were more like 1.4 GW (with 1.7 GW shipped).
That wasn't my mistake, but in my other post --
http://groups.google.com/group/alt.solar.photovoltaic/msg/9766268eea5dead7
-- I did some math based on that figure, which will also need
correction.
I estimated that California will be adding 0.30 GW of demand to the PV
market per year, over the next ten years. I concluded that this was an
insignificant fraction of the present world-wide demand -- 0.30 GW out
of 14 GW is just two percent. But with the decimal point corrected,
0.30 GW per year is about 21% of the demand. That's pretty
significant, though I still don't think it's enough to raise PV prices.
I remember reading some rumors that California is also proposing to
provide incentives for in-state PV production. That would help. There
was something about a 100 MW/year PV factory in the works. Anyone?
Eeyore
axol...@hotmail.com wrote:
Oh dear !
You asked a pertinent question ! Shut that man up !
Actually it would need about 150 million 200 watt panels. Simply because (a) you
don't get the full power output all the time the sun's shining and also very
little during the winter months and (b) you get no power at all at dawn / dusk /
night !
OTOH a power station provides its 3GW day in, day out 24/7 !
If you do the sums you'll se that that 1 million homes don't even have remotely
enough roof area to do the job, never mind it might take several decades to make
the PV cells required. And of course cost about $150 billion for 3GW of
electricity. Utter madness.
It simply isn't going to happen simply because it's nor possible ! Then I expect
a few politicians having got egg on their faces might start questioning the
entire 'bogus science' behind PV.
PV only makes sense where there is *no grid* for power and even then only in
limited situations.
Graham
Eeyore
SJC wrote:
There's a far worse reality. The sun doesn't shine 100% all the time. Very, very far from it !
http://www.powerfromthesun.net/chapter1/images/figure1_6.gif
Graham
Eeyore
"R.H. Allen" wrote:
Unfortunately it simply can't work for far more fundamental scientific issues !
See 'insolation'.
Graham
Eeyore
John Ladasky wrote:
> R.H. Allen wrote:
> > axol...@hotmail.com wrote:
> > > Wouldn't 3GW peak require about 15 million 200 watt panels? The world
> > > installed about 14GW total in 2005; how's this going to affect the
> > > availability and price of panels?
> >
> > I think you dropped a decimal point -- worldwide installations in 2005
> > were more like 1.4 GW (with 1.7 GW shipped).
>
> That wasn't my mistake, but in my other post --
>
> http://groups.google.com/group/alt.solar.photovoltaic/msg/9766268eea5dead7
>
> -- I did some math based on that figure, which will also need
> correction.
>
> I estimated that California will be adding 0.30 GW of demand to the PV
> market per year, over the next ten years. I concluded that this was an
> insignificant fraction of the present world-wide demand -- 0.30 GW out
> of 14 GW is just two percent. But with the decimal point corrected,
> 0.30 GW per year is about 21% of the demand. That's pretty
> significant, though I still don't think it's enough to raise PV prices.
>
> I remember reading some rumors that California is also proposing to
> provide incentives for in-state PV production. That would help. There
> was something about a 100 MW/year PV factory in the works. Anyone?
You'll need a huge *silicon* factory first ! It'll need more than the entire
global semiconductor requirement for silicon most likely just to pursue a flawed
idea.
Even then it would take 30 years to do it ! And be massively energy negative and
*contribute* to pollution and global warming in the process !
At least it'll kill off PV in the long term so we won't have to suffer their
inane babble any longer.
Graham
LongmuirG
> At least it'll kill off PV in the long term so we won't have to suffer their
> inane babble any longer.
Back in the 1970s & 80s, the State of California did a pretty good job
of kneecapping the then-solar industry -- by offering big tax rebates
on things like solar swimming pool heating systems. (That's right.
Help the poor!) When the tax rebates were later withdrawn, the
industry was floored. So now history repeats. The whole PhotoVoltaic
industry depends heavily on politically-controlled subsidies in Germany
& California. Not good.
Is there a better way? How about something similar to the X-prizes for
space engineering. One wild thought -- $1 Billion cash from the State
of California to the first company which sells 10,000 unsubsidized
solar energy systems in CA -- no tax rebates, no subsidies, no
preferential pricing on the power produced. Plus $500 Million for the
second company, and $250 Million for the third company. Point of the
prize would be to make sure money gets spent on improving the
technology so that solar energy can compete on a level playing field.
Eeyore
LongmuirG wrote:
Even if PV panel efficiency improved by a factor of 3:1 ( a stupendous leap )
they'd be pissing in the wind still.
It's simple economic viability ( or the absence of it ) that'll kill PV.
Graham
Mark
R.H. Allen wrote:
> I think you dropped a decimal point -- worldwide installations in 2005
> were more like 1.4 GW (with 1.7 GW shipped).
Woops, my bad! The source said 1430MW and I mistranslated.
brenmcn
Folks,
Solar PV still needs a big breakthrough to deliver on the hopes. In the
UK it would cost $63Bn to generate a full GWe-year from current panels.
For a simple comparison of the total costs of complete systems of
Rooftop power, Coal, Gas, Wind, and Nuclear go to
http://cestar.seas.ucla.edu. Their 'papers' file shows my article on
Electricity and my Uranium article which shows how nuclear could run
10,000 reactors for several thousand years.
California, being sunny, could be 3-4 times more cost effective with
Solar PV, bringing the price down to only $20Bn per GWe-year. Nanosolar
may cut this further. There are many excellent ways to use Solar PV,
but replacing power stations is not yet one of them. Carter tried this
in 1980 - I was working in DoE at the time and read all their Solar
docs. - and the technology has not improved greatly since then.
California should go nuclear, not solar.
Brendan McNamara
daestrom
"Eeyore" <rabbitsfriend...@REMOVETHIS.hotmail.com> wrote in
message news:44F0C188...@REMOVETHIS.hotmail.com...
>
>
> axol...@hotmail.com wrote:
>
>> Wouldn't 3GW peak require about 15 million 200 watt panels? The world
>> installed about 14GW total in 2005; how's this going to affect the
>> availability and price of panels?
>
> Oh dear !
>
> You asked a pertinent question ! Shut that man up !
>
> Actually it would need about 150 million 200 watt panels. Simply because
> (a) you
> don't get the full power output all the time the sun's shining and also
> very
> little during the winter months and (b) you get no power at all at dawn /
> dusk /
> night !
>
> OTOH a power station provides its 3GW day in, day out 24/7 !
>
Why do you rant on about this? The bill doesn't say anything about the
energy production, nor does it compare the energy production of 3 GW of
solar panels versus the energy production of a 3GW power station.
Seems you have confused the power rating of 3GW of solar with the energy
production of a 3GW plant operating 100% capacity factor.
Having 3GW of solar, which of course only produces during sunny days, does
reduce the number of peaking plants needed. While a base-load power plant
may run 24/7, many peaking units only run a very few hours on only some
days. An equivalent 3GW in peaking units would not be needed if 3GW of
solar came on-line to supply the daily peak load.
Since peaking units, such as the ones these solar panels replace, generate
electricity at very high costs, then the solar panels *can* be an economic
option.
Even without subsidies, at $5 / watt over their lifetime, just four hours a
day, that $5 can generate 25kwh or more. That's $0.20/kwh. Peaking units
can run upwards from $0.20/kwh to as high as $1.50/kwh.
Which is 'utter madness', paying $0.20/kwh peak, or $1.50/kwh??
Is solar a good choice for base-load, or complete replacement? No, of
course not. The average price of grid electricity is cheaper. But it *is*
a good replacement for peaking capacity and peak power costs.
But I suppose where you are it rains too much, and you don't have the kind
of mid-day peaking that we have in the US. Maybe you should do some
research about the places you're criticising.
daestrom
SJC
"brenmcn" <bre...@leabrook.co.uk> wrote in message news:1156668737....@m79g2000cwm.googlegroups.com...
http://re.jrc.cec.eu.int/pvgis/pv/countries/countries-europe.htm
Eeyore
SJC wrote:
> I came across these solar maps of Europe, thought they were good.
> http://re.jrc.cec.eu.int/pvgis/pv/countries/countries-europe.htm
Much obliged for that !
Where I live for example ( near London UK ) it looks like the yearly solar insolation is ~ 980 kWh / m^2..
So 1 m^2 of solar panel @ 10% efficiency would produce 98 kWh annually or an average of 11W.
The value of the electricity produced would be ~ £10 p.a. The cost of a suitable size panel is ~ £500.
http://www.unlimited-power.co.uk/kyocera_solar_panels_pv_modules_uk.html
Actually, these panels say they offer 15% efficeincy so that's £15 worth of electricity produced each year. I'll
give it a miss thanks !
Graham
LongmuirG
> Even without subsidies, at $5 / watt over their lifetime, just four hours a
> day, that $5 can generate 25kwh or more. That's $0.20/kwh. Peaking units
> can run upwards from $0.20/kwh to as high as $1.50/kwh.
> Is solar a good choice for base-load, or complete replacement? No, of
> course not. The average price of grid electricity is cheaper. But it *is*
> a good replacement for peaking capacity and peak power costs.
Daestrom, did you really mean to say *is* or *may some day be* a good
replacement?
If our current inadequate solar technology could provide reliable peak
power at about 1/8 the cost of alternatives, the solar industry would
be building peaking plants all over the place, and the politicians
would be talking about taxing "Big Sun" instead of throwing out
pointless subsidies.
I suspect the issue comes back to the (un)reliability of that (solar)
peak power. Until we can store energy efficiently, photovoltaics are
probably going to continue to be a very minor contributor -- and of
course, energy storage would push up that $0.20/kWh quite a bit.
Interestingly, once economical energy storage does become available,
then solar will have to compete with baseload nuclear plants running at
a steady rate 24/7 with storage to handle the peaks.
SJC
"LongmuirG" <Long...@aol.com> wrote in message news:1156693447....@p79g2000cwp.googlegroups.com...
can be better than 70%, including losses for evaporation. So if you want to
store energy, just pump water up a hill and make electric on the way down.
However, since PV is not likely to be much more that a few percent of our
power generation and peak summer loads are so high, putting it on the grid
makes the most sense.
R.H. Allen
>
> axol...@hotmail.com wrote:
>
>> Wouldn't 3GW peak require about 15 million 200 watt panels? The world
>> installed about 14GW total in 2005; how's this going to affect the
>> availability and price of panels?
>
> Oh dear !
>
> You asked a pertinent question ! Shut that man up !
>
> Actually it would need about 150 million 200 watt panels.
Actually, you seem to have missed the word "peak". Nobody is suggesting
that 3 GW of PV will produce as much energy as 3 GW of conventional
baseload capacity. In reality it will produce between 15% and 25% as
much as 3 GW of conventional baseload plants, but PV is not a baseload
technology so the comparison is a lousy one. If you compare PV to other
peaking technologies -- that is, compare apples to apples -- it is a
much more favorable comparison (both energy- and cost-wise).
> OTOH a power station provides its 3GW day in, day out 24/7 !
A baseload power station does, provided it's not down for refueling or
maintenance (coal and nuclear plants average 70-80% uptime, though the
best manage 90%). Peaking power plants run much less often -- IIRC,
their capacity factors average something like 40% in the US.
> If you do the sums you'll se that that 1 million homes don't even have remotely
> enough roof area to do the job, never mind it might take several decades to make
> the PV cells required. And of course cost about $150 billion for 3GW of
> electricity. Utter madness.
If you do the sums *properly* you'll see that the typical home has more
than enough roof space to provide for its own energy needs with PV.
There are many, many examples of such homes all over the world, you just
have to open your eyes and look for them.
R.H. Allen
>
> John Ladasky wrote:
>
>> I remember reading some rumors that California is also proposing to
>> provide incentives for in-state PV production. That would help. There
>> was something about a 100 MW/year PV factory in the works. Anyone?
>
> You'll need a huge *silicon* factory first !
There are quite a few of them in the works.
> It'll need more than the entire
> global semiconductor requirement for silicon most likely just to pursue a flawed
> idea.
>
> Even then it would take 30 years to do it !
Well, you got something right: Silicon PV was first commercialized about
30 years ago, and in 2006 the amount of silicon used by the PV industry
will surpass that used by the microelectronics industry.
> And be massively energy negative and
> *contribute* to pollution and global warming in the process !
There are dozens and dozens of studies performed over the last several
decades refuting those points. I have tried and tried to find studies by
PV detractors concluding the opposite, but those I've found -- if they
address these issues at all -- concede that PV is overwhelmingly energy
positive (in fact, the time required to recover the energy used in
making a PV module is just about the same as that required for a coal or
nuclear plant). On the global warming front, the worst criticism I've
found is a study concluding that in years that PV shipments increase by
more than 30% PV manufacturing activities *temporarily* contribute to
global warming, but the long-term effect is overwhelmingly in favor of
global warming mitigation.
If you're aware of any rigorous criticisms that support your assertion I
would love to know what they are.
R.H. Allen
> Eeyore wrote:
>> At least it'll kill off PV in the long term so we won't have to suffer their
>> inane babble any longer.
>
> Back in the 1970s & 80s, the State of California did a pretty good job
> of kneecapping the then-solar industry -- by offering big tax rebates
> on things like solar swimming pool heating systems. (That's right.
> Help the poor!) When the tax rebates were later withdrawn, the
> industry was floored. So now history repeats.
Maybe. One of the problems with the subsidies of the '70s and '80s was
the way they were structured and the way they were withdrawn. They
basically encouraged price gouging and offered no incentive for
manufacturers and installers to reduce prices. The new California
subsidy is based on Japan's recently ended subsidy program, which
gradually reduced subsidies year after year to discourage price gouging
and encourage price reductions. In Japan it worked out quite well -- PV
prices are now fairly competitive with grid prices in Japan and their PV
market is nearly as strong now as it was before the subsidies ended.
> The whole PhotoVoltaic
> industry depends heavily on politically-controlled subsidies in Germany
> & California. Not good.
I agree with that. The industry is far too subsidy-driven, and that
needs to end as soon as possible.
R.H. Allen
>
> I suspect the issue comes back to the (un)reliability of that (solar)
> peak power. Until we can store energy efficiently, photovoltaics are
> probably going to continue to be a very minor contributor -- and of
> course, energy storage would push up that $0.20/kWh quite a bit.
IIRC, several analyses (including at least one by the Department of
Energy) have concluded the US grid could be up to 20-30% PV before
storage technology would be required. That would make it as significant
a contributor as nuclear and natural gas. Even at half that, it would
still be more significant than hydro.
LongmuirG
> The renewables group went over pumped hydro a while back. Efficiency
> can be better than 70%, including losses for evaporation. So if you want to
> store energy, just pump water up a hill and make electric on the way down.
Yes. Good plan. All we need (in addition to the source of surplus
power) is water & topography. And those are the limitations on pumped
storage. There are few places which have the right combination of
resources -- pumped storage in London or Khartoum? Those few places
which do have the right combination of resources have mainly already
been built out.
So let's just recognize that pumped storage is great where it is great,
and useless everywhere else. What is the economic energy storage
option for everywhere else?
daestrom
>> Even without subsidies, at $5 / watt over their lifetime, just four hours
>> a
>> day, that $5 can generate 25kwh or more. That's $0.20/kwh. Peaking
>> units
>> can run upwards from $0.20/kwh to as high as $1.50/kwh.
>> ...
>> Is solar a good choice for base-load, or complete replacement? No, of
>> course not. The average price of grid electricity is cheaper. But it
>> *is*
>> a good replacement for peaking capacity and peak power costs.
>
> Daestrom, did you really mean to say *is* or *may some day be* a good
> replacement?
>
> If our current inadequate solar technology could provide reliable peak
> power at about 1/8 the cost of alternatives, the solar industry would
> be building peaking plants all over the place, and the politicians
> would be talking about taxing "Big Sun" instead of throwing out
> pointless subsidies.
>
Perhaps I was being overly optimistic. But the *one* place where PV is a
good match and is likely to succeed is in peaking power production in
climates that use a large amount of A/C (such as southern California). This
is one use where the reliability of PV doesn't become a big factor. When
the sun doesn't shine, the A/C load is lower so not as much peaking power is
required.
IMHO, PV will *not* replace any form of base-load for a long time to come.
So I don't agree with those that believe that PV will enable us to shut down
all the coal/nuclear/<fill in undesirable plant type>.
The economics of PV depend strongly on the cost of peaking power plants and
the nature of the load causing the 'peaking'. For example, here in the
northeast, where peaking is caused by both A/C in summer and heating in the
winter, PV could not replace a peaker since PV would not have the
availability needed in winter.
So, while this initiative may work in California to reduce the costs of peak
power, I don't believe it is a 'universal fix' that can be applied
everywhere.
> I suspect the issue comes back to the (un)reliability of that (solar)
> peak power. Until we can store energy efficiently, photovoltaics are
> probably going to continue to be a very minor contributor -- and of
> course, energy storage would push up that $0.20/kWh quite a bit.
But if PV is *only* used during A/C load peaks, then storage is not
required. Yes, this limits PV to a small percentage of installed capacity,
and will not replace base-load. I agree with you on that. But for those
special locales that have major peaking caused by major sunshine (A/C
loads), then PV is a good match up.
> Interestingly, once economical energy storage does become available,
> then solar will have to compete with baseload nuclear plants running at
> a steady rate 24/7 with storage to handle the peaks.
>
IMHO, *that* combination has got a long way to go before it can compete with
coal/nuclear. THAT quantity of storage, quite frankly, is mind-bogglingly
huge. Imagine just two days worth of storage at 1/3 the baseload for
something like the PJM?? At 4:00 AM this morning, PJM's load was still
~65000 MW. So 48 hours worth of storage of 1/3 of that would be 1040 GW-hr
(1.0e12 Joules). And that's just for 2 days, probably not nearly enough.
And sooner or later, someone will realize that storing that much energy,
whether as pumped water or ??? is going to be just a tad dangerous.
Especially if something can trigger its release all at once (such as a dam
failure).
daestrom
daestrom
"daestrom" <daestrom@NO_SPAM_HEREtwcny.rr.com> wrote in message
news:R7mIg.23886$uH6....@twister.nyroc.rr.com...
Oops, got my sums wrong. 1/3* 65e9*48*3600=3.7e15 Joules.
(if this were pumped storage at 80%, and the elevation difference was 50 m,
that would be ~9e9 m^3 of water. If the reservoir was 20 m deep, that would
be an area of about 478 km^2. Of course it would be broken up into several
storage facilities, but still, that's a *lot* of water )
daestrom
LongmuirG
> ...
> IMHO, *that* combination has got a long way to go before it can compete with
> coal/nuclear. THAT quantity of storage, quite frankly, is mind-bogglingly
> huge. Imagine just two days worth of storage at 1/3 the baseload for
Point taken. But I was imagining something along the lines of a coal
or nuclear plant operating at a steady output which more or less
bisected the roughly sinusoidal daily demand curve. For about 12
hours, the plant would be feeding any energy it produced in excess of
demand into the storage device, and for about 12 hours the energy
storage would be making up the difference between demand & the plant's
level output.
However, your point is absolutely spot on. Even that would be a lot of
stored energy. And any conceivable store of a lot of reasonably
accessible energy is always going to have an element of risk.
Your broader point about photovoltaics is also a good one --
photovoltaic energy should be able to fill some niche uses, like power
for air conditioning in sunny locations. I keep stumbling over the
obvious follow up -- if it is such a good idea, why is it not being
done on a large scale today? The obvious answer is that photovoltaics
are not economic today, even for those niche uses. The other possible
answer is that photovoltaics really do not fit the niche properly -- in
many sunny areas, the need for air conditioning goes up after the sun
goes down, because of the increase in Relative Humidity as the
temperature drops.
I have no beef against photovoltaics -- but it is no panacea; at the
moment it is not even a factor worth considering. If someone like
William Mook can bring the installed cost of photovoltaics down by a
factor of 50, then it begins to look interesting.
Eeyore
daestrom wrote:
> Why do you rant on about this?
Because it's bollocks ?
> The bill doesn't say anything about the
> energy production, nor does it compare the energy production of 3 GW of
> solar panels versus the energy production of a 3GW power station.
The publicity does.
> Seems you have confused the power rating of 3GW of solar with the energy
> production of a 3GW plant operating 100% capacity factor.
The media has.
> Having 3GW of solar, which of course only produces during sunny days, does
> reduce the number of peaking plants needed. While a base-load power plant
> may run 24/7, many peaking units only run a very few hours on only some
> days. An equivalent 3GW in peaking units would not be needed if 3GW of
> solar came on-line to supply the daily peak load.
So why is the publicity comparing it to 3GW of nuclear ?
> Since peaking units, such as the ones these solar panels replace, generate
> electricity at very high costs, then the solar panels *can* be an economic
> option.
>
> Even without subsidies, at $5 / watt over their lifetime, just four hours a
> day, that $5 can generate 25kwh or more. That's $0.20/kwh. Peaking units
> can run upwards from $0.20/kwh to as high as $1.50/kwh.
Please show your calculations for $0.20/kWh
Graham
Eeyore
LongmuirG wrote:
There's also an issue that the peaking generation still has to be there to
provide the power on 'rainy' days and during the darker months!
http://www.powerfromthesun.net/chapter1/images/figure1_6.gif
You simply can't eliminate the need for it.
Graham
Eeyore
"R.H. Allen" wrote:
Wind power is vastly more useful.
And *cheap* !
Graham
Eeyore
"R.H. Allen" wrote:
> Eeyore wrote:
> >
> > axol...@hotmail.com wrote:
> >
> >> Wouldn't 3GW peak require about 15 million 200 watt panels? The world
> >> installed about 14GW total in 2005; how's this going to affect the
> >> availability and price of panels?
> >
> > Oh dear !
> >
> > You asked a pertinent question ! Shut that man up !
> >
> > Actually it would need about 150 million 200 watt panels.
>
> Actually, you seem to have missed the word "peak". Nobody is suggesting
> that 3 GW of PV will produce as much energy as 3 GW of conventional
> baseload capacity.
The publicity I've seen seems to suggest this though.
> In reality it will produce between 15% and 25% as
> much as 3 GW of conventional baseload plants, but PV is not a baseload
> technology so the comparison is a lousy one.
Tell that to the media !
> If you compare PV to other
> peaking technologies -- that is, compare apples to apples -- it is a
> much more favorable comparison (both energy- and cost-wise).
>
> > OTOH a power station provides its 3GW day in, day out 24/7 !
>
> A baseload power station does, provided it's not down for refueling or
> maintenance (coal and nuclear plants average 70-80% uptime, though the
> best manage 90%).
I rather thought nuclear was way better than that actually ( and probably the others
too ) .
> Peaking power plants run much less often -- IIRC,
> their capacity factors average something like 40% in the US.
>
> > If you do the sums you'll se that that 1 million homes don't even have remotely
> > enough roof area to do the job, never mind it might take several decades to make
> > the PV cells required. And of course cost about $150 billion for 3GW of
> > electricity. Utter madness.
>
> If you do the sums *properly* you'll see that the typical home has more
> than enough roof space to provide for its own energy needs with PV.
> There are many, many examples of such homes all over the world, you just
> have to open your eyes and look for them.
Ok, let's just look at 3GW peak from a million homes.
Each home would have to generate 3kW at peak insolation. A 1 m^2 panel will generate ~
100W at peak insolation in that area using the best technology currently available..
To generate 3kW would require 30 such panels or 30m^2 ( 300 sq ft ! ) and cost ~
$15,000.
So, you get 3kW of peak only electricity at only certain times of the day and in
summer only for an outlay of ~ $15 billion !
Sounds pretty dumb to me !
How much does good insulation and 'solar glass' cost in comparison ? Peanuts.
Graham
John Ladasky
You can't really value every kilowatt-hour equally. Three questions
determine the value of electricity:
1) Where is it produced?
2) When is it produced?
3) How is it produced?
California recognizes this, and has started to push the use of TOU
(time-of-use) electric meters. I got one installed when I went solar.
I pay -- OR I am paid -- $0.294/kWh for "summer peak" power (April -
October, weekdays, from noon to 6:00 PM). Summer off-peak power is
just $0.086/kWh. "Winter peak" power is $0.117/kWh, and winter
off-peak is $0.090/kWh.
http://pge.com/rates/tariffs/ResTOUCurrent.xls
We have a special problem here in California -- grid strain. During
heat waves, we have to move around way too much power. We've had
failures when main interties reached their limits. We have also had
local failures -- transformers at local substations are asked to carry
so much current that they overheat and fail.
Distributed, local sources of energy connected to every sub-station
would be VERY useful. But these power stations would also need to be
good neighbors, because they have to exist in close proximity to
people. The "how is it produced" question becomes very important.
I can't put a useful windmill on the roof of my California suburban
home -- the neighbors would tar me, feather me, and hang me from the
tower. There is no acceptable site for a windmill anywhere in my
rotating outage block. We are too built-up. Besides, the nearest good
ridge-line is several miles away.
Should we also have wind power? Of course. California has several
large wind farms, and more are on the way. We produced 4446 GWh of
electricity using wind in 2005, 1.5% of our total use, five times as
much as we produced using solar.
http://www.energy.ca.gov/electricity/gross_system_power.html
I promise you that not one kWh of that wind power was generated on lots
smaller than an acre, though.
Understand this: California is virtually cloudless for six months out
of the year. PV output is at its highest, and quite dependable,
precisely when we have high demand and grid-reliability problems.
+-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-+
| Ladasky Home Solar, Inc.: blowing sunshine up your |
| power grid since March 24, 2005. Fiat lux! |
+-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-+
| Uptime Downtime kWh generated kWh consumed |
| 520 days 6.5 hours 9908 9838 |
+-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-+
Mark
Eeyore wrote:
> To generate 3kW would require 30 such panels or 30m^2 ( 300 sq ft ! ) . .
Which would be 12'x20', easily fit on a rooftop.
Tony Wesley
For sufficiently large values of 12.
Dan Bloomquist
daestrom wrote:
>
> Perhaps I was being overly optimistic. But the *one* place where PV is
> a good match and is likely to succeed is in peaking power production in
> climates that use a large amount of A/C (such as southern California)...
It may not be PV, it may be solar thermal electric...
http://ec.europa.eu/energy/res/sectors/solar_thermal_power_en.htm
And it may get better:
http://www.sandia.gov/news-center/news-releases/2004/renew-energy-batt/Stirling.html
The reason, they could get this down to a buck a peak watt in the next
decade. Maybe thin film is on their heals, but that was the story almost
a decade ago. Whichever, it is about that buck a watt threshold.
Best, Dan.
Dan Bloomquist
Eeyore wrote:
>
>
> The publicity...
So you have been caught at a strawman rant and now you hold up your
strawman???
do...@xrexxmilli.usenet.us.com
> I keep stumbling over the obvious follow up -- if it is such a good idea,
> why is it not being done on a large scale today? The obvious answer is
> that photovoltaics are not economic today, even for those niche uses.
You surmise that as the obvious answer.
There may be many reasons why home PV installations are not more popular.
Panel availability may be one.
Lack of desire to make a financial commitment might be one.
Some lack the financial standing to make the commitment, even if they might
want to buy a PV system.
Some don't believe that it can be true, that it's a scam.
I project the economic viability of my PV system based on avoided energy
costs, which I calculate each month.
PG&E has a announced another rate hike. This one makes the news because it
will affect "tier 2" levels of users, where the previous 10 years have
seen a drop of 2% in the electric rate, from $0.133 to $0.129/kWh.
My electrical usage has not been constrained to those lower tiers. My
pre-solar usage strayed into the higher realms, where 96-current has seen
rate increases of 80-250%.
PV in California looks like a very good deal to me.
It should look like a good deal to my neighbor, who had $500 PG&E bills
last summer, but the high cost of the system required to offset that level
of usage was too much of a commitment.
There is initial negative cash flow in my projections, but that is a burden
that I believe will be well worth while in the long run. Maybe others
don't take a long view of their investments.
--
---
Clarence A Dold - Hidden Valley Lake, CA, USA GPS: 38.8,-122.5
http://cdold.home.mchsi.com/Solar-generation.htm
Eeyore
Mark wrote:
Eh ?
That's 240 sq ft !
Graham
R.H. Allen
> daestrom wrote about energy storage:
>> ...
>> IMHO, *that* combination has got a long way to go before it can compete with
>> coal/nuclear. THAT quantity of storage, quite frankly, is mind-bogglingly
>> huge. Imagine just two days worth of storage at 1/3 the baseload for
>> something like the PJM?? ...
>
> Point taken. But I was imagining something along the lines of a coal
> or nuclear plant operating at a steady output which more or less
> bisected the roughly sinusoidal daily demand curve. For about 12
> hours, the plant would be feeding any energy it produced in excess of
> demand into the storage device, and for about 12 hours the energy
> storage would be making up the difference between demand & the plant's
> level output.
>
> However, your point is absolutely spot on. Even that would be a lot of
> stored energy. And any conceivable store of a lot of reasonably
> accessible energy is always going to have an element of risk.
>
> Your broader point about photovoltaics is also a good one --
> photovoltaic energy should be able to fill some niche uses, like power
> for air conditioning in sunny locations. I keep stumbling over the
> obvious follow up -- if it is such a good idea, why is it not being
> done on a large scale today? The obvious answer is that photovoltaics
> are not economic today, even for those niche uses.
Much of the answer to that question depends on where you are -- not just
because of the climate, but because of the local cost of electricity and
how it's billed. In many cases in Japan, for example, unsubsidized PV is
economical. As I recall, in the early days of the debate about the bill
in California that started this thread the bill was primarily supported
by Republicans because their analysis suggested that the $2.9 billion in
taxpayer money spent would be more than made up for in savings to
utility ratepayers. (The underlying logic behind their calculation was
to estimate the amount of PV fed to the grid during peak hours and
compare the cost of the subsidy to the cost of an equivalent amount of
electricity bought on the spot market during peak hours.)
One thing that certainly works against PV is its high up-front cost. The
largest cost associated with a coal plant is for fuel, which is
purchased over the life of the plant, whereas for PV almost the entire
investment is made up front. There has been many a thread in these
newsgroups with folks saying they'd need a 7-10 year economic payback
period before they'd consider installing a PV system; assuming the PV
system lasts 30-35 years, they're essentially saying PV must be
available at 20-33% of grid rates before they'll buy it. Perhaps that
attitude will change in the future, particularly if PV systems
significantly increase the market price of a home, but that remains to
be seen.
> The other possible
> answer is that photovoltaics really do not fit the niche properly -- in
> many sunny areas, the need for air conditioning goes up after the sun
> goes down, because of the increase in Relative Humidity as the
> temperature drops.
>
> I have no beef against photovoltaics -- but it is no panacea; at the
> moment it is not even a factor worth considering. If someone like
> William Mook can bring the installed cost of photovoltaics down by a
> factor of 50, then it begins to look interesting.
Well, a factor of 50 would bring the economic payback period down to
just three years or so....
LongmuirG
the economics of photovoltaics:
> There is initial negative cash flow in my projections, but that is a burden
> that I believe will be well worth while in the long run. Maybe others
> don't take a long view of their investments.
Ummm -- that is exactly what is meant by "economics". Any real process
requires an initial investment, whether it is a windmill or a nuclear
power plant, followed by a period of return on that investment -- cash
in at the beginning, followed by cash out over a relatively long period
of time.
>From what you describe, many Californians view the economics of home
photovoltaics as being unattractive. The return is not enough to
justify the investment, in their assessment.You may disagree with their
assessment, just as they may see you as wasting your scarce capital on
an underperforming investment. That is the magic of markets -- lots of
individuals get to make their own judgments, and time will tell who was
correct.
If the news media are to be believed (silly statement, I know!), over
the last few years Californians have seen the value of their homes rise
substantially, and many of them have taken advantage of low interest
rates to get cash out of their homes through second mortgages. Point
is, most Californians have had access to capital to pay for the front
end costs of a home photovoltaic system -- if they had wanted to. Most
Californians clearly did not want to, which suggests their assessment
is that home photovoltaic systems are not economically attractive.
R.H. Allen
>
> There's also an issue that the peaking generation still has to be there to
> provide the power on 'rainy' days and during the darker months!
> http://www.powerfromthesun.net/chapter1/images/figure1_6.gif
>
> You simply can't eliminate the need for it.
True, but the peaks are generally smaller on rainy days and during the
darker months. Whether PV goes up and down in the same proportion is
likely a function of location and time of year, but it doesn't make PV
useless any more than the fact that droughts occur everywhere makes
hydro useless.
R.H. Allen
It's only cheap where the wind blows strongly enough, and that doesn't
happen everywhere. I gather that you're in the UK, where long distance
transmission isn't that big a deal. In the much larger US there's
technically enough wind to power the entire country, but it's not evenly
distributed by any means. The limitations of long-distance transmission
mean that wind power is neither useful nor cheap in many US locations.
One study I'm aware of suggests that wind can provide no more than about
20% of the US electricity supply before transmission issues cap its
growth. Now maybe it will never get that big to begin with, but it's
worth keeping in mind.
R.H. Allen
>
> "R.H. Allen" wrote:
>
>> Eeyore wrote:
>>> axol...@hotmail.com wrote:
>>>
>>>> Wouldn't 3GW peak require about 15 million 200 watt panels? The world
>>>> installed about 14GW total in 2005; how's this going to affect the
>>>> availability and price of panels?
>>> Oh dear !
>>>
>>> You asked a pertinent question ! Shut that man up !
>>>
>>> Actually it would need about 150 million 200 watt panels.
>> Actually, you seem to have missed the word "peak". Nobody is suggesting
>> that 3 GW of PV will produce as much energy as 3 GW of conventional
>> baseload capacity.
>
> The publicity I've seen seems to suggest this though.
Okay, then I'll amend my statement: Nobody *knowledgeable* is suggesting
this. Remember, it's also the media who were responsible for the
statement that nuclear power would one day be "too cheap to meter."
>> In reality it will produce between 15% and 25% as
>> much as 3 GW of conventional baseload plants, but PV is not a baseload
>> technology so the comparison is a lousy one.
>
> Tell that to the media !
People have, but they seem to think the concept is too difficult for the
general public.
>> If you compare PV to other
>> peaking technologies -- that is, compare apples to apples -- it is a
>> much more favorable comparison (both energy- and cost-wise).
>>
>>> OTOH a power station provides its 3GW day in, day out 24/7 !
>> A baseload power station does, provided it's not down for refueling or
>> maintenance (coal and nuclear plants average 70-80% uptime, though the
>> best manage 90%).
>
> I rather thought nuclear was way better than that actually ( and probably the others
> too ) .
I blurred the lines between uptime and capacity factor a little --
sorry. Just because a plant is running doesn't mean its running at full
power, so there's often a small discrepancy between the two. Capacity
factor is the more accurate metric for the amount of energy produced by
a plant, though.
According statistics from the US Department of Energy, nuclear plants in
the US had a collective capacity factor of 88% in 2003, up from about
70% in the mid-'90s. Also in 2003, the collective capacity factor for
coal plants in the US was 72%; for natural gas, 36% (and that's being
generous, as I'm counting all energy produced from natural gas but not
including natural gas capacity from dual-fired plants, which inflates
the capacity factor number); for petroleum, 37%; and for hydro, 31%.
Nuclear and coal together provide about 70% of US electricity, and the
rest are used primarily to meet peak demand.
>> Peaking power plants run much less often -- IIRC,
>> their capacity factors average something like 40% in the US.
>>
>>> If you do the sums you'll se that that 1 million homes don't even have remotely
>>> enough roof area to do the job, never mind it might take several decades to make
>>> the PV cells required. And of course cost about $150 billion for 3GW of
>>> electricity. Utter madness.
>> If you do the sums *properly* you'll see that the typical home has more
>> than enough roof space to provide for its own energy needs with PV.
>> There are many, many examples of such homes all over the world, you just
>> have to open your eyes and look for them.
>
> Ok, let's just look at 3GW peak from a million homes.
>
> Each home would have to generate 3kW at peak insolation. A 1 m^2 panel will generate ~
> 100W at peak insolation in that area using the best technology currently available..
Using the *best* technology currently available a 1 m^2 panel will
produce about 170 W at peak insolation, but the best technology is not
required -- 100 W/m^2 will do just fine.
> To generate 3kW would require 30 such panels or 30m^2 ( 300 sq ft ! ) and cost ~
> $15,000.
>
> So, you get 3kW of peak only electricity at only certain times of the day and in
> summer only for an outlay of ~ $15 billion !
What, that's all there is to your analysis? Peak power output is only
one aspect of the system. How much energy will the system produce? How
much energy does the average home *need*? How do they compare? How much
do the other system components cost? What's the final cost per kWh?
A typical grid-connected home is designed such that the total amount of
energy generated is about what the home requires. This means it
generates a lot of extra electricity during peak hours, which is given
to the power company. At night, the power company gives the electricity
back. It's a good deal for everybody -- the power company gets expensive
peak electricity in exchange for less valuable off-peak electricity; the
distributed generation can also ease the strain on the transmission
system. The homeowner has no electricity bill and gets to use the power
grid for energy storage.
> Sounds pretty dumb to me !
You don't even know how much the energy from a PV system will cost!
Pronouncing it "dumb" after your analysis is uninformed at best. (FYI,
unsubsidized residential PV in the US currently costs some
$0.30-0.40/kWh; for industrial and commercial systems it's more like
$0.20/kWh.)
> How much does good insulation and 'solar glass' cost in comparison ? Peanuts.
If you'd bothered to learn anything about the PV industry you would know
that PV advocates, including PV companies themselves and reputable PV
installers, advise that folks considering PV invest in energy efficiency
*first*. It's cheaper than PV, as you point out, and it also reduces the
amount of PV you need to power your home.
Mark
Like 15'! Slip of the keyboard, should be 15'x20', or 10'x30, etc.
do...@xrexxmilli.usenet.us.com
> photovoltaics as being unattractive.
Again, that is what you surmise.
I would say that more find the physical appearance unattractive, and far
more have never given it any thought at all.
> Point is, most Californians have had access to capital to pay for the
> front end costs of a home photovoltaic system -- if they had wanted to.
Many of the refinancings were to lower monthly payments and take advantage
of reduced rates. Much of the "cash out" was used to pay down credit card
debt, allowing consumers to add more debt. But, I ramble on about
what I perceive, living in the state.
> Most Californians clearly did not want to
Most Californians have never even thought about solar.
It is easy to continue buying energy from PG&E. Those at the lower end of
the economic strata have no choice. They don't own a home, or are heavily
leveraged with debt. The energy rates at the lower usage levels haven't
gone up in 10 years, so, if they don't have high energy consumption, they
have no incentive at all to look elsewhere. With the exception of one day
of publicity about the million solar roof plan, there is no seed planted in
the mind of the public.
Those at the higher end of the economic strata don't care about the cost.
They are more concerned with how the PV panels might disrupt the
architecture. There was a posting in this group within the last month or
so from someone who purchased more panels than he needed, beyond what the
net metering agreements would reimburse, so that he could cover one side of
his roof. The glaring aesthetics of a break in the roof design were more
important than the money involved.
John Ladasky
I watch with great enthusiasm the progress being made by combining
solar thermal collectors and Stirling engines. I predict that, a
decade from now, California will be generating thousands of GWh per
year using this technology.
The fact remains that transmitting power is as big an issue in
California as is generating it. My suburban substation would benefit
greatly from having local sources of peak power. However, every inch
of land here is already spoken for.
The neighbors won't let me mount a big parabolic mirror on my roof, any
more than they would allow me to install the windmill that was
mentioned earlier. Solar PV is the way to go for my location, and for
the millions of places just like it here in California.
Yes, it costs more. But, as I discussed in another post, not all
kilowatt-hours are created equal. Nor should they be valued equally.
Under the current electricity market rules, payback for my system will
be achieved in eleven years -- not as quickly as many of my other
investments, perhaps, but it's hardly the total loss that many PV
naysayers have claimed.
John Ladasky
> > Point is, most Californians have had access to capital to pay for the
> > front end costs of a home photovoltaic system -- if they had wanted to.
> Most Californians have never even thought about solar.
>
> It is easy to continue buying energy from PG&E. Those at the lower end of
> the economic strata have no choice. They don't own a home, or are heavily
> leveraged with debt. The energy rates at the lower usage levels haven't
> gone up in 10 years, so, if they don't have high energy consumption, they
> have no incentive at all to look elsewhere. With the exception of one day
> of publicity about the million solar roof plan, there is no seed planted in
> the mind of the public.
>
> Those at the higher end of the economic strata don't care about the cost.
> They are more concerned with how the PV panels might disrupt the
> architecture. There was a posting in this group within the last month or
> so from someone who purchased more panels than he needed, beyond what the
> net metering agreements would reimburse, so that he could cover one side of
> his roof. The glaring aesthetics of a break in the roof design were more
> important than the money involved.
Exactly right, Clarence! Even here in the land of sunshine and energy
crises, most Californians have never even considered solar.
You are right that there are basically two classes of Californians --
too poor, and too rich. The poor ones can't get the up-front money for
solar, and the rich ones can already afford to keep their central air
conditioning running all the time, whatever the cost.
The same rationale is at work when people go shopping for new cars. If
you're squeezed, you'll buy a Ford Focus, perhaps, or a Hyundai Accent.
If you're loaded, you'll walk right by the hybrids and shop for a BMW
SUV.
The sweet spot, where the consumer is neither too poor to buy Green nor
too wealthy to care, is really quite narrow.
Having said that, I'm modestly annoyed with the look of my PV system.
I have 27 modules in two rows, and my stringers stick out from the side
of the array. Pictures here:
I ALMOST have the money to do what that other person you mentioned did
-- buy more PV, and as a consequence, tidy up the appearance of my
roof. I have room for seven more modules -- in fact, that's why my
stringers extend out to the end of the roof. One of my two inverters
is only half-used.
Three things might push me to make the upgrade:
First possibility -- it's my understanding that the Million Solar Roofs
Initiative will be changing the rules about selling surplus power. Can
anyone confirm this? Right now, the rules say that you receive credits
over a twelve-month period for surplus power that you generate. But
the utility never pays you. If you bring your annual bill down to
zero, that's as low as you can go. The rest of your surplus power is a
gift to the grid. It's for this reason that Californians who go solar
at home often install a system which provides just 70% of their power,
but then they also install a TOU meter. They can cover 100% of their
bill with such a system, because they are generating a lot of power
during the summer peak, but they generally aren't using much power at
that time.
Second possibility -- I might need more electricity soon. I predict
that my next big environmental purchase will be a PHEV upgrade for my
Prius -- or better yet, if they're available, an entirely new, smaller
PHEV to replace my 1994 Honda Civic.
Third possibility -- if grid reliability becomes substantially worse
here, I might need to switch to islanding inverters and add a battery
backup system. This arrangement is inherently lower in efficiency than
a grid-tied system. So, to maintain the same level of output, I will
need more modules.
Eeyore
John Ladasky wrote:
> Under the current electricity market rules, payback for my system will
> be achieved in eleven years
Show me the sums !
Graham
do...@xrexxmilli.usenet.us.com
<rabbitsfriend...@removethis.hotmail.com> wrote:
> John Ladasky wrote:
My June 17, 2006, accounting from PG&E shows -176 kWh peak,
326 kWh off-peak, 150 kWh overall, billing of $-25.77.
The Peak was charged/credited in Tier 1 and Tier 2 at $.29372.
The off-peak was charged/credited in Tier 1 and Tier 2 at $.08664.
My solar system produced 698kWh, so I consumed 848kWh.
Solar was 82% of my energy, over 100% of my bill.
Using non-solar rates, $146.87 avoided PG&E billing for June.
The projection is for me to avoid $1457 in PG&E charges this year.
My projection includes a ROI break even in year 11, at which point the
avoided costs are projected to have risen to $2730. In order for this to
happen, utility rates need to rise 6.5% per annum. If that fails to
happen, and nuclear power does become too cheap to meter, I will have lost
money. On the other hand, the tier 4 rates have gone up 80% in the last 10
years, 22% since I installed my system, so I should come out okay.
Willia...@gmail.com
materials by a factor of 500! This is achieved in two ways. The first
reduces parasitic heating by increasing voltage or reducing resistance.
Sater received a patent on the first concept with his innovative VMJ
(vertical multijunction) design. Swanson received a patent on the
second concept with his point junction or back junction design, which
removed a sparse array from the front of the solar cell. Sater's
design allows increases in light intensity by factors of 1,000 and
more. Swanson allows increases in light intensity by factors of more
than 100!
Mok designed CPV systems use a combination of back-junction (think of
the PN junction as a twinkie instead of a sandwich) combined in series
(without the junction losses of Swanson's VMJ) - which virtually
eliminates parasitic or i-squared-R heating effects.
The next problem is that associated with a black body radiation source.
The sun sits in the vacuum of space and it loses energy principally by
radiation. So, it looks very much like a black body radiator operating
at 5,770K - so, there is this Planck curve that rises and peaks around
550 nm wavelength and tails off to nothing well past 1,500 nm.
Well, silicon operates at about 1,100 nm. This means that photons with
wavelengths longer than 1,100 nm don't operate the solar cell. They
just heat it. And it also means that photons with wavelengths shorter
than 1,100 nm contribute only the bandgap energy of 1,100 nm to the
operation of the cell. So, photons with wavelengths of 550 nm for
example only contribute half their energy to the operation of the solar
cell. Photons with wavelengths of 367 nm only contribute 1/3 of their
energy to the operation of the solar cell. Unusued energy shows up as
heat.
Mok designed CPV systems use a dichroic filter in front of the PV cells
to create an optical bandpass filter that rejects a lot of heat while
impacting the operation of the solar cell very little. Sure, we reject
some useful energy, but we reject a lot of heat, and that means we can
concentrate the light to higher levels and reduce PV costs more.
Another feature of our CPV system is water-filled lenses. These lenses
are molded out of PET and joined together in a water bath. The focal
point of the lenses is inside the optical medium, and the solar cells
reside at that point, surrounded on all sided by water. Convective
cooling around the solar cell is sufficient to keep the cell cool under
all conditions. Each lens body is about 1 square inch in area and each
PV device has an active area of 1 square millimeter. This is a factor
of greater than 600x - and there's no active cooling and no complex
devices at all. We basically have two hot-press molded sheets that are
bonded together in a water bath with a sparse array of PV cells. The
cost of each 4' x 8' x 1-1/2" sheet in production is less than $40!
The output of each sheet is 580 watts under ideal illumination!
This CPV system uses a proprietary method that involves light
interaction across many lenses to avoid the need of tracking the sun
across the sky. This allows the sheet of over 4,000 lenses per panel
to operate largely as a flat plate system. Once we have firm patents
established for this process I'll be glad to share it with the public.
But this makes it very easy to install and operate our panels.
With production prices this low installation costs can be a factor. A
24' x 24' array of panels involving 18 panels each 4x8 feet, cost a
total of $720 at the factory and produce over 10 kW peak. Installing
shingles on your roof can cost $10 per square foot just for labor.
That's over $5,000 in this case! So, there's a strong argument - at
these prices - for centralized installation on the ground. That's why
Mok has designed systems that consist of 1,100 panels wired together in
a 4,400 foot string - think of Christmas tree light strings -
containing 550 separate circuits that terminate at either end of the 8'
wide band. These are conveniently z-folded onto a 53' flat bed trailer
and shipped anywhere for easy installation. A simple connection at
either end of the string connects to our patented sodium sulfur
variable load flow batteries if you want to produce electrons, or our
variable load electrolyzer if you want to produce protons.
Peak power matching is important as the lighting conditions change
throughout the day. So, being able to vary the load attached to a
solar panel is important. This is usually accomplished electronically
in more conventional installations and costs around $0.40 per peak
watt. This is unacceptably high for our panels, so we created a low
cost solution.
Sodium comes from salt, and salt along with sulfur are inexpensive when
compared to lead. So, a sodium sulfur battery costs about 1/10th the
cost of lead acid by weight. Now, sodium sulfur also has about 11x the
storage capacity by weight as lead acid. This means that energy
storage with a sodium sulfur setup is less than 1% that of lead acid.
Unfortunately this system requires molten sulfur solution and liquid
sodium solutions to work, and that's a problem for home installation,
but for industrial installations, especially stationary ones, its not
really an issue. For each peak watt at least 5 watt-hours of storage
are needed to maintain constant power out. This adds about 2 cents per
peak watt to the overall cost - in production. Since most of the cost
is the ceramic electrolyte for the batteries, flow batteries are a
natural choice for very large capacities which can be achieved at very
low costs - allowing 50 to 100 watt-hours per peak watt to be
efficiently stored.
Mok electrolysis systems are configured using our proprietary variable
load technology as well. So we can efficiently produce hydrogen. The
systems involve nothing more than a series of stainless steel
electrodes in a water bath with pottasium hydroxide catalyst. The
electrodes are situated beneath headers that collect the hydrogen and
oxygen. The entire system operates at 12,000 psi, and the oxygen is
blown out through a specially built turbine. The energy generated is
used to compress water coming into the system. The hydrogen is blown
down into piplines that operate at 10,000 psi. A simple float system
keeps the water at header height. While stainless steel electrodes and
water are not suitable for mobile applications, and while PEM
technology is far more efficient, in terms of capital efficiency, the
Mok system is best - producing hydrogen at extraodinarily low costs.
While hydrogen can be used directly as fuel and delivered through
pipelines, Mok favors the use of high pressure hydrogen to directly
hydrogenate carbon sources. Carbon dioxide can be made into methane
and water, using the Sabatier process. low-rank carbon sources like
coal, biological materials, asphalts, etc., can be hydrogenated into
higher rank oils using a variant of the Bergius process. Oil can be
sold more easily than hydrogen or DC electricity.
Going back to our 24ft x 24ft array consisting of 3 strings of 6 panels
each - a small tank type enclosure that's 8 ft long and 4 ft in
diameter, is sufficient to provide 100 kWh of storage for $200, while
providing the ability to vary the load on the solar array to provide
peak power matching.
So, for less than $1,000 - a home can be provided for. The entire
system can be shipped in a 96 inch x 48 inch x 75 inch volume and
ground installed in very little time. An AC intertie operating at 5kW
peak, driven by the DC battery pack, would cost on the order of $2,000
- a total cost of $3,000 - plus installation and shipping. 24 systems
could be placed into a single truck and shipped anywhere. So, total
installed costs could be $4,500 -
While the availability of sunlight on any given day is unpredictable,
the availability of sunlight over the course of the year is well known.
This is similar to the situation that occurs with tossing a coin. Its
hard to predict heads or tails in a single toss. But in 1,000 tosses,
its easy to see that about 500 will be heads and 500 tails.
In sunny locales in North America there may be as many as 2,500 hours
of sunlight in a given year. In less sunny places, this can drop to
1,250 hours of sunlight. But this is the range.
The lifespan of the system described here is 16+ years with 99%
effectiveness at the end of the period. In that time. That's 20,000 to
40,000 hours of sunlight. With 10,000 watts peak, that's 200,000,000
to 400,000,00 watt hours. Of course this all isn't peak, since there
are cosine losses. So for an optimally oriented system, there is 70.7%
of the peak power available throughout the day on average. So, the
earlier figure falls to 140,000,000 to 280,000,000 watt hours,depending
on location. With a total cost of $4,500 this is an installed cost of
1.6 to 3.2 cents per kWh.
Installing and maintaining an home energy appliance may cost an
additional 3 to 4 cents per kWh over the life of the equipment. Since
this is less than the wheeling costs of transmitting electrical energy
long distances, this suggests again, that large central installations
in sunny regions are preferred.
This is why Mok proposes using rail rights of way to transmit HVDC
electricity around the country on a new HVDC network. Then, selling for
less than 20 cents per peak watt, intertie equipment for use by
utilities to replace generators and drive their older AC grids. This
would allow the utilities to shut down their coal fired power plants,
and replace them with emission free intertie equipment. Since
installation and maintenance costs are far lower for centralized sites,
and since central sites can be located in the sunniest of regions, we
can deliver solar electric power to utilities through an HVDC network
for as little as 3 to 4 cents per kWh.
Hydrogen produced from water can also be transmitted by pipeline, and
used in a variety of ways. The coal saved from coal fired power plants
would be hydrogenated directly to produce liquid fuels like gasoline,
diesel fuel, and jet fuel. These fuels could displace foreign oil. The
US uses about 1 billion tons per year of coal for power plants.
Replacing all coal fired generators with solar powered HVDC
electricity, and using that coal to make 6 billion barrels of oil,
would not increase our carbon load, but would provide for the nation's
oil supply and give the US control of its energy future. This is all
be powered from lands leased from mining companies in Nevada and
Arizona. Coal is taken from Powder River Basin,Wyoming. Water comes
from Utah's Great Salt Lake. Salt is used in battery production.
Hydrogen is used to clean coal forming hydrogen sulfide. This is
reduced by electrolysis to hydrogen again, and elemental sulfur, which
is used in battery production as well. Chlorine is sold to industry's
that use cholorine, like P&G and others.
The cost of oil produced in this way is about $12 per barrel. The cost
of electricity ranges from 2 cents per kwh to 4 cents per kwh -
depending on distance shipped. The HVDC network also ties the entire
US together in a new way making the system more stable.
The entire system costs $800 billion and will take 14 years to
complete. To make the oil requires massive production of hydrogen at
very low cost. This source of low cost hydrogen can be tapped by
innovators and businesses in ways to displace oil production and
transition to a hydrogen economy.
daestrom
Well, I just have to 'throw a flag on the play' there :-)
Yes, RH rises as outside temperature falls. But the vapor pressure and
latent heat load does not rise just because of that. If you look at a
psychrometric chart and plot the locations of 90% at 80F and 56% at 95F,
you'll find that the actual moisture content in the air is the same
(humidity ratio is still just 0.0707. The amount of moisture that will be
removed in a well-adjusted A/C unit in both cases is about the same.
RH is very deceptive because it is 'relative' to what the air could contain,
and that value changes with temperature as well. Dew-point can be a much
better way to monitor the humidity levels.
>
> I have no beef against photovoltaics -- but it is no panacea; at the
> moment it is not even a factor worth considering. If someone like
> William Mook can bring the installed cost of photovoltaics down by a
> factor of 50, then it begins to look interesting.
Agreed there. He's been doing some interesting work with focusing systems.
That could provide some 'quantum' price reductions (pun intended :-)
daestrom
daestrom
"Eeyore" <rabbitsfriend...@REMOVETHIS.hotmail.com> wrote in
message news:44F21810...@REMOVETHIS.hotmail.com...
You don't *need* the peaking generation if the major load during the 'peak'
is related to sunshine (i.e. A/C load). The 'peak' in winter time for some
areas is non-existent. Unfortunately for me, in NY, the peak in winter is
about the same as summer, so PV is *not* a winner here.
But in places like southern California, or Florida, where much of the daily
'peak' is caused by A/C, the peak load disappears on rainy days and 'darker
months'. Don't need a lot of peaking generation to supply a load that isn't
there.
So supplying some or a major portion of 'peak' load with PV is a good match,
*in those specific circumstances*. The fact that PV is a lousy fit where
you are is bad luck. But don't be so provincial that you can't see that
other locales are different and can make better use of PV.
daestrom
Eeyore
Willia...@gmail.com wrote:
> Concentrating Photovoltaics have the capacity to reduce the cost of PV
> materials by a factor of 500! This is achieved in two ways. The first
> reduces parasitic heating by increasing voltage or reducing resistance.
> Sater received a patent on the first concept with his innovative VMJ
> (vertical multijunction) design. Swanson received a patent on the
> second concept with his point junction or back junction design, which
> removed a sparse array from the front of the solar cell. Sater's
> design allows increases in light intensity by factors of 1,000 and
> more. Swanson allows increases in light intensity by factors of more
> than 100!
Err........ So a 1 m^2 PV cell can take 500kW of energy input ( without melting
) ?
Graham
Tim Ward
"daestrom" <daestrom@NO_SPAM_HEREtwcny.rr.com> wrote in message
news:_ILIg.42740$1Z5....@twister.nyroc.rr.com...
Yes.
Interestingly, (to me at least) the solar thermal peaking plant at Kramer
Junction nearly went bust when natural gas prices went up a few years ago.
It turns out the steam for the turbines can be generated either by natural
gas, or the solar array.
Apparently, the peak price times the availability of just the solar array is
not profitable -- at least if you're having to guarantee availability.
They're still running, as far as I know, so they must have figured out
something.
Tim Ward
Eeyore
daestrom wrote:
> "Eeyore" <rabbitsfriend...@REMOVETHIS.hotmail.com> wrote in
> message news:44F21810...@REMOVETHIS.hotmail.com...
>
> > There's also an issue that the peaking generation still has to be there to
> > provide the power on 'rainy' days and during the darker months!
> > http://www.powerfromthesun.net/chapter1/images/figure1_6.gif
> >
> > You simply can't eliminate the need for it.
>
> You don't *need* the peaking generation if the major load during the 'peak'
> is related to sunshine (i.e. A/C load). The 'peak' in winter time for some
> areas is non-existent. Unfortunately for me, in NY, the peak in winter is
> about the same as summer, so PV is *not* a winner here.
Quite so.
> But in places like southern California, or Florida, where much of the daily
> 'peak' is caused by A/C, the peak load disappears on rainy days and 'darker
> months'. Don't need a lot of peaking generation to supply a load that isn't
> there.
OK.
> So supplying some or a major portion of 'peak' load with PV is a good match,
> *in those specific circumstances*. The fact that PV is a lousy fit where
> you are is bad luck. But don't be so provincial that you can't see that
> other locales are different and can make better use of PV.
I can see the case but even so, the demand for a/c will significantly lag the
availability of PV power due to thermal time constants, so it'll never be a
perfect match.
Graham
LongmuirG
> > Well, I just have to 'throw a flag on the play' there :-)
>
> Yes, RH rises as outside temperature falls. But the vapor pressure and
You are right -- no disagreement at all on that. However, the issue I
was driving at was the suitability of solar power to drive air
conditioning units. It is a common observation in many areas that
people do *not* switch off their AC units as soon as the sun goes down
-- in part because the Relative Humidity effect can make people feel
less comfortable then even though the thermometer says that the
temperature is going down. Air conditioning dehumidifies the air as
well as cooling it.
But if we are depending on the sun to keep our air conditioning going,
then we are out of luck after sunset.
Windsun
Please explain to me how you can turn a 100 watt panel into a 5000 watt one
by concentrating.
-------------------------------------------------------------------------
<Willia...@gmail.com> wrote in message
news:1156807371.6...@75g2000cwc.googlegroups.com...
Windsun
over 100.
-------------------------------------------------------------------------
"LongmuirG" <Long...@aol.com> wrote in message
news:1156823328.8...@i42g2000cwa.googlegroups.com...
Anthony Matonak
> Concentrating Photovoltaics have the capacity to reduce the cost of PV
> materials by a factor of 500!
Hasn't so far. Every concentrating PV system developed so far has
wound up costing pretty much the same as any other PV system.
> So, for less than $1,000 - a home can be provided for.
I've got $1,000. Where do I buy one?
Anthony
nicks...@ece.villanova.edu
>If you look at a psychrometric chart and plot the locations of 90% at 80F
>and 56% at 95F, you'll find that the actual moisture content in the air
>is the same (humidity ratio is still just 0.0707.
7%?
Nick
nicks...@ece.villanova.edu
>Baloney.
>
>Please explain to me how you can turn a 100 watt panel into a 5000 watt one
>by concentrating.
That's only 50. Piece of cake :-)
>-------------------------------------------------------------------------
><Willia...@gmail.com> wrote:
>> Concentrating Photovoltaics have the capacity to reduce the cost of PV
>> materials by a factor of 500!
Nick
R.H. Allen
The question of whether or not the cell melts depends on how quickly
heat is removed, but as I recall a silicon wafer in still air will get
very hot, but not melt under such concentrations (and of course, the
still air would start moving as heat transferred from the silicon and
began a convection current). I could be mistaken about that, but the
point is moot because the temperatures achieved are too high for
effective solar cell operation and some form of cooling is required for
the system to work.
The cells also must be designed for such concentrations -- the contacts
on a solar cell designed for 1 sun will quickly burn up under the
currents generated by 500X concentration. Other aspects of the cell need
to be redesigned as well, generally those relating to the internal
resistance of the solar cell, but a well designed concentrator cell will
have a higher efficiency at high concentration than under 1 sun, and
typically a higher efficiency than a similar cell optimized for 1 sun.
Problem is, concentrators aren't very effective in areas that see much
cloudy weather -- the clouds scatter the sunlight and prevent it from
being focused.
R.H. Allen
>
> daestrom wrote:
>
>> So supplying some or a major portion of 'peak' load with PV is a good match,
>> *in those specific circumstances*. The fact that PV is a lousy fit where
>> you are is bad luck. But don't be so provincial that you can't see that
>> other locales are different and can make better use of PV.
>
> I can see the case but even so, the demand for a/c will significantly lag the
> availability of PV power due to thermal time constants, so it'll never be a
> perfect match.
Again, it depends on where you are. A number of utilities -- including
some in California, as I recall, and at least one in the southeastern US
-- have published plots of their demand curves against PV output in the
region and they match up pretty well. That doesn't happen everywhere,
but it certainly *does* happen.
Willia...@gmail.com
R.H. Allen wrote:
> Eeyore wrote:
> >
> > Willia...@gmail.com wrote:
> >
> >> Concentrating Photovoltaics have the capacity to reduce the cost of PV
> >> materials by a factor of 500! This is achieved in two ways. The first
> >> reduces parasitic heating by increasing voltage or reducing resistance.
> >> Sater received a patent on the first concept with his innovative VMJ
> >> (vertical multijunction) design. Swanson received a patent on the
> >> second concept with his point junction or back junction design, which
> >> removed a sparse array from the front of the solar cell. Sater's
> >> design allows increases in light intensity by factors of 1,000 and
> >> more. Swanson allows increases in light intensity by factors of more
> >> than 100!
> >
> > Err........ So a 1 m^2 PV cell can take 500kW of energy input ( without melting
> > ) ?
>
> The question of whether or not the cell melts depends on how quickly
> heat is removed, but as I recall a silicon wafer in still air will get
> very hot, but not melt under such concentrations (and of course, the
> still air would start moving as heat transferred from the silicon and
> began a convection current). I could be mistaken about that, but the
> point is moot because the temperatures achieved are too high for
> effective solar cell operation and some form of cooling is required for
> the system to work.
Its not the melting that's the problem, long before the melting of
things become a problem semi-conductive silicon becomes too conductive
to operate properly. Our cells operate close to 100C junction
temperature, which means they're still pretty efficient.
>
> The cells also must be designed for such concentrations -- the contacts
> on a solar cell designed for 1 sun will quickly burn up under the
> currents generated by 500X concentration.
Our cells are totally immersed in water, so they cool from both sides,
and they have a dichroic coating,which reflects ineffective
wavelengths. 60% of the energy is reflected away, and 28% is conducted
away as electricity, this means that only 12% of the incident energy
must be sunk into the water bath the solar cell finds itself.
Now direct sunlight is the kind that can be focused. And on a clear
sunny day that amounts to 850 watts per square meter. That's 85
milliwats per square centimeter.
So, at 700x concentration, of direct sunlight 85 milliwatts per square
centimeter becomes 59.5 watts per square centimeter. Now, only 12% of
this ends up as heat to be conducted away into the water bath, so
that's 7.14 watts per square centimeter of sunlight, but since the
water bath covers both sides, that's down to nearly 3 watts per square
centimeter, which is easily handled by convective water currents in the
water filled lens.
Important to note that the solar cell produces 16.7 watts per square
centimeter. At $0.16 per square centimeter, this is only 1 cent per
peak watt electrical for PV material.
> Other aspects of the cell need
> to be redesigned as well, generally those relating to the internal
> resistance of the solar cell, but a well designed concentrator cell will
> have a higher efficiency at high concentration than under 1 sun, and
> typically a higher efficiency than a similar cell optimized for 1 sun.
True. The reduction of dark current losses relative to forward current
helps here.
> Problem is, concentrators aren't very effective in areas that see much
> cloudy weather -- the clouds scatter the sunlight and prevent it from
> being focused.
True. But in cloud free skies they work great! Will they work in your
area? There's an easy way to tell. Do you ever see your shadow when
you're walking outside in daylight? If you do, then concentrator
arrays described here will work great. Remember, these are non-imaging
lenses. That's important to know. This allows me to avoid hot spots
that imaging systems might produce, but it also lets me work in less
than ideal conditions as well over the field of view of the system.
Willia...@gmail.com
Windsun wrote:
> Baloney.
>
> Please explain to me how you can turn a 100 watt panel into a 5000 watt one
> by concentrating.
You're right. Your understanding of what I said *is* baloney! lol.
So, take a step back and know that you are mistaken.
Take a square centimeter of PV material. It costs about $0.16 and
fabricated the way we do it, is about 33% efficient under full spectrum
illumination. Now, there is about 850 watts per square meter of direct
sunlight on a clear sunny day at the Earth's surface. And there are
10,000 square cenitmeters in a square meter. So, that's 85 milliwatts
per square centimeter. At 33% efficiency you've got 28 milliwatts
electrical from this setup costing $0.16 - That's $5.71 per peak watt.
Now, take two pieces of PET plastic totalling 200 micons thick and mold
them into lens like surfaces, bond them together in a water bath, and
you end up with a water filled container that focuses sunlight falling
on it. The PET plastic and water cost less than 1/300th of a penny per
square centimeter!! But that lens takes 85 milliwatts and focuses it
to a point only half a millimeter across! The cost of the lens per
watt of sunlight handled is about 1/26th of a penny per watt.
Now, the light at that tiny point is 700 times brighter than it is
falling on the lens in the first place. The solar cell at that point
is only 1/700th the size of the lens in area. So, its cost is only
1/700th the size of a solar cell needed without the lens. So, the cost
is less than 1 cent per peak watt.
So, I replace a solid surface of solar cells with a sparse array of
solar cells and a solid surface of low cost lenses. This reduces costs
to $0.07 per peak watt while allowing me to make 700x as much surface
out of a given amount of wafer material than a conventional panel.
Willia...@gmail.com
Anthony Matonak wrote:
> Willia...@gmail.com wrote:
>
> > Concentrating Photovoltaics have the capacity to reduce the cost of PV
> > materials by a factor of 500!
>
> Hasn't so far. Every concentrating PV system developed so far has
> wound up costing pretty much the same as any other PV system.
Yes, balance of systems costs take their toll. Each part of the system
has to be redesigned to effect a large reduction. This requires
billions of dollars of investment to produce a complete system as I've
described.
>
> > So, for less than $1,000 - a home can be provided for.
>
> I've got $1,000. Where do I buy one?
New Castle Pennsylvania, August 2009.
> Anthony
Anthony Matonak
Ok, I guess I'll have to get back to you in three years.
Anthony
nicks...@ece.villanova.edu
>The cells also must be designed for such concentrations -- the contacts
>on a solar cell designed for 1 sun will quickly burn up under the
>currents generated by 500X concentration. Other aspects of the cell need
>to be redesigned as well, generally those relating to the internal
>resistance of the solar cell, but a well designed concentrator cell will
>have a higher efficiency at high concentration than under 1 sun, and
>typically a higher efficiency than a similar cell optimized for 1 sun.
>Problem is, concentrators aren't very effective in areas that see much
>cloudy weather -- the clouds scatter the sunlight and prevent it from
>being focused.
How about 2-3 suns on a standard panel with water trickling over
the front surface?
Nick
John Ladasky
Thank you, Clarence, you spared me the trouble. This is pretty much
the same economic analysis that my PV contractor supplied me. However,
looking over your math, I realized that my electrical use rarely
exceeds Tier 2. I never get into Tier 4. So my monetary payback time
will actually be somewhat longer than eleven years.
On a related subject, my energy payback time -- the time it takes for
my PV system to produce the amount of energy that was needed to
manufacture it -- is independent of the billing schedule. And current
studies show that the energy payback time in sunny places like
Australia or California is eight to eleven years.
http://groups.google.com/group/alt.energy.homepower/msg/8f89d0b682359fc7
Windsun
build up, and probably algae on the panel. And you need energy to pump the
water, and more maintenance.
-------------------------------------------------------------------------
<nicks...@ece.villanova.edu> wrote in message
news:ed1r7a$a...@acadia.ece.villanova.edu...
daestrom
<nicks...@ece.villanova.edu> wrote in message
news:ed0odv$9...@acadia.ece.villanova.edu...
Nope, my bad. That's the density. I read the wrong scale.
The humidity ratio is 140.2 grains per pound of dry air (0.02 lbm water per
lbm of dry air)
daestrom
daestrom
"Tim Ward" <tjw...@charter.net> wrote in message
news:lwMIg.2261$cR....@newsfe06.lga...
>
> "daestrom" <daestrom@NO_SPAM_HEREtwcny.rr.com> wrote in message
> news:_ILIg.42740$1Z5....@twister.nyroc.rr.com...
Yes, when you start looking at day-ahead or further scheduling, the price
you can get for power varies quite a bit between 'firm' and
'unit-contingent' pricing.
Most power purchase agreements don't have a clause of, "well, if it's not
too hot that day because it's cloudy, we'll forgive you not being
available." Depends a lot on the customer and what their loading looks
like.
And don't even get started about the transmission scheduling fees. Bid with
the ISO for some MW's of transmission capacity and then don't use it? No,
you don't get a refund.
For an independent generator, the variability of PV would have a big impact
on the pricing they could get for their power.
daestrom
P.S. But for the 'million PV homes', those issues aren't quite the same.
do...@xrexxmilli.usenet.us.com
> Thank you, Clarence, you spared me the trouble. This is pretty much
> the same economic analysis that my PV contractor supplied me. However,
> looking over your math, I realized that my electrical use rarely
> exceeds Tier 2. I never get into Tier 4. So my monetary payback time
> will actually be somewhat longer than eleven years.
My usage on the E1 schedule, prior to solar installation, was heavy T3,
some T4, and a little T5 in the summertime. I provided 18 months billing
data to the salesman, which was used to prepare the ROI and system sizing.
After installing the PV, those high tiers are gone.
> On a related subject, my energy payback time -- the time it takes for
> my PV system to produce the amount of energy that was needed to
> manufacture it -- is independent of the billing schedule. And current
> studies show that the energy payback time in sunny places like
> Australia or California is eight to eleven years.
http://www.hespul.org/Vous-cherchez-des-statsitiques-des.html
"2.1 Energy Pay-Back Time (EPBT)
For rooftop-mounted PV systems, the range of EPBT is between 1.6 and 3.3
years, with the best case in Perth, Australia and the worst case in
Edinburgh, UK."
Jim Baber
Eeyore wrote:
>do...@XReXXMilli.usenet.us.com wrote:
>
>
>
>>In alt.solar.photovoltaic Alex Terrell <alext...@yahoo.com> wrote:
>>
>>
>>
>>>They mean 3GW of capacity, which is 3KW each peak, which is about 30m2.
>>>
>>>
>>My array is 3.8KW, 33m2, 52'x7'.
>>http://cdold.home.mchsi.com/Solar-generation.htm
>>
>>
>>
>>>That's a pretty big solar array - so it seems to me the numbers don't
>>>add up.
>>>
>>>
>>The numbers look right. Whether that's too big is in the eye of the
>>beholder. Mine is roof mount. My neighbor's is ground mount.
>>
>>Jim has a 10 kw system that is larger than his roof.
>>
>>
>
>Hardly surprising for 10kW. To generate 10kW year round would take ~ 10,000 sq
>ft !
>
>Graham
>
My 10 kW system has actually produced an average of 46.122 kWh each day
since it was turned on over 3 years ago on the 15th of June 2003 in
Fresno Ca. Fresno is not the best place for solar, but it is better
than some. Fresno has 2 major problems:
1. In the summer it is too hot, in the 76 days since the 15th of
June, our 5 PM temperature has averaged 99.8 F. and this reduces
the power output of solar cells.
2. There were 42 days last winter when we had our infamous "tule fog"
which does not lift at all. I still got some power most days.
There were only 2 days without any production, but none of those
foggy days were over 9.0 kW for the day. That is a long way from
my average.
By the way Graham, I actually have 1625 sq. ft. of solar panels on my
roof, not 10,000. My wife says the astronauts use us as a landmark when
they land at Edwards AFB. I admit it looks like a lot, but the roof
actually has a total of about 4,750 sq. ft. when you have to buy new
shingles for it. I did just before I put the panels up.
--
Jim Baber
Email j...@NOJUNKbaber.org
1350 W Mesa Ave.
Fresno CA, 93711
(559) 435-9068
(559) 905-2204 (Verizon IN cellphone (to other Verizon IN accounts))
See 10kW grid tied solar system at "http://www.baber.org/solarpanels.jpg"
See solar system production data at "http://www.baber.org/solar_status.htm"
Jim Baber
mike...@yahoo.com wrote:
>Well with 3KW you can still run some stuff. It's better than a total
>blackout, and this way the homes can contribute power to the grid instead of just
>sucking it up.
>
I wish that were true, but in order to get any of the benefits from the
rebate program, you MUST tie to the grid, and if you are tied to the
grid, your system MUST shut if the grid shuts down. The power companies
will not allow you to continue to generate power when they shut the grid
down, theoretically because of the dangers to their crews. In order to
avoid problems with the power companies and to prevent overloading their
inverters, most of the manufacturers of inverters capable of grid
connection have included automatic shutdown for their inverters when the
inverter senses the loss of the grid power. Overloading would occur,
because not only would you be supplementing the grid (like normally) you
would be trying to feed the entire grid by yourself and Boulder Dam you
aren't.
do...@xrexxmilli.usenet.us.com
> I wish that were true, but in order to get any of the benefits from the
> rebate program, you MUST tie to the grid, and if you are tied to the
> grid, your system MUST shut if the grid shuts down.
Your system needn't shut down. It must stop putting power onto the grid.
What you do behind a properly installed transfer switch is up to you. The
Outback inverter has a built in transfer switch.
b...@fractalfreak.com
Eeyore wrote:
>
> You'll need a huge *silicon* factory first ! It'll need more than the entire
> global semiconductor requirement for silicon most likely just to pursue a flawed
> idea.
>
> Even then it would take 30 years to do it ! And be massively energy negative and
> *contribute* to pollution and global warming in the process !
>
>
> Graham
It does take a lot of energy to produce a 'traditional' PV
(Si) cell, but they do produce more energy during their
life than went into making them
It takes no more than five years for cell to pay off
the energy that went into making it, and considering they
have lifespans measured in decades they certainly are
net producers of energy.
Makes more sense than the lame ethanol/biodiesal scams
you trumpet, which *are* energy losers no matter how
you look at it.
:P
Eric B
b...@fractalfreak.com
> Windsun wrote:
> > Baloney.
> >
> > Please explain to me how you can turn a 100 watt panel into a 5000 watt one
> > by concentrating.
>
>
> You're right. Your understanding of what I said *is* baloney! lol.
> So, take a step back and know that you are mistaken.
>
Sounds somewhat similar to what this guy in Australia is doing:
http://www.greenandgoldenergy.com.au/
He's taking very expensive triple-junction cells and then using
concentrator arrays on them. The (apparent) advantages are
somewhat reduced cost (the cells are very expensive, but he
doesn't need many of them) - $3/watt, and they work more efficiently
at high temperatures. The cells are placed on a large heatsink, and
the triple junction cells are designed to work at higher temps than
regular Si cells. Check the site out.
Eric
R.H. Allen
The water would help keep the panels cool, but it would do nothing about
the resistive losses in the module. I suspect most, if not all, 1 sun
modules could handle it for a short time, but that the length of time a
module could handle it would be a bit of a crapshoot -- some would do
better than others, but it might be difficult to tell which without
actually trying them. The best I can do, though, is guess, since there
isn't much in the way of data to back me up.
Eeyore
Jim Baber wrote:
I confess, I was out by one zero on my number.
I'm going to take a stab at your peak power being indeed ~ 10kW using around 160 sq
metres of panels.
Let's say you need ~ 50 panels for 3kW. Let's say you can get those panels for ~
$500 in bulk.
To fit a million homes with that amount of PV would cost $25 billion in solar
panels alone before even factoring in labour and the cost of the grid-tie
inverters. Easily what ? $ 40 bn ? Damn pricey !
Graham
Eeyore
b...@fractalfreak.com wrote:
> Eeyore wrote:
> >
> > You'll need a huge *silicon* factory first ! It'll need more than the entire
> > global semiconductor requirement for silicon most likely just to pursue a flawed
> > idea.
> >
> > Even then it would take 30 years to do it ! And be massively energy negative and
> > *contribute* to pollution and global warming in the process !
> >
> >
> > Graham
>
> It does take a lot of energy to produce a 'traditional' PV
> (Si) cell, but they do produce more energy during their
> life than went into making them
>
> It takes no more than five years for cell to pay off
> the energy that went into making it,
Not in most places.
> and considering they
> have lifespans measured in decades they certainly are
> net producers of energy.
>
> Makes more sense than the lame ethanol/biodiesal scams
> you trumpet, which *are* energy losers no matter how
> you look at it.
How is bio-fuel a net loss ?
Graham
Willia...@gmail.com
b...@fractalfreak.com wrote:
> Willia...@gmail.com wrote:
> > Windsun wrote:
> > > Baloney.
> > >
> > > Please explain to me how you can turn a 100 watt panel into a 5000 watt one
> > > by concentrating.
> >
> >
> > You're right. Your understanding of what I said *is* baloney! lol.
> > So, take a step back and know that you are mistaken.
> >
>
> Sounds somewhat similar to what this guy in Australia is doing:
> http://www.greenandgoldenergy.com.au/
Yes, we've been working with Spectrolab and their UTJ cells.
http://www.spectrolab.com/images/press/SPL_UTJ_Anncmnt.pdf#search='spectrolab%20utj'
>
> He's taking very expensive triple-junction cells and then using
> concentrator arrays on them. The (apparent) advantages are
> somewhat reduced cost (the cells are very expensive, but he
> doesn't need many of them) - $3/watt, and they work more efficiently
> at high temperatures.
The temperature thing is a misnomer. Optimum temps are 28C as noted in
the article above. They are more efficient however since they use a
bigger part of the spectrum.
> The cells are placed on a large heatsink,
Yes, because they can't get too hot!
> and
> the triple junction cells are designed to work at higher temps than
> regular Si cells. Check the site out.
Again, while Ge substrate and GaAs and InPh all can operate at a higher
temp than Si, the UTJ stack likes the 28C operating point. That's my
only quibble.
But this suncube design requires a sun-tracker,and involves 3M fresnel
lens sheets. These were first developed for overhead projectors and
adapted for solar energy use. 3M does not sell these cheaply, and no
one buys them in sufficient quantity to be practical yet! Although 3M
is producing advanced stretched fresnel optics
http://www.entechsolar.com/SpacePaper5.pdf#search=%223m%20fresnel%20lens%20solar%22
Which are interesting.
Water filled lenses of the type I've described previously made of
low-cost PET hot press molded is far cheaper than precision formed
silicone held prefectly in place by an aluminum structure over an
aluminum heat sink sheet. Steps in the right direction to be sure, but
far behind what I have achieved.
> Eric
Willia...@gmail.com
I can send you detailed designs of my plant and product.