Taking Solar Power To New Heights
Steve Spence
From: "Steve Spence" <ssp...@webconx.com>
To: "Energy - WebConX" <ene...@webconx.com>
Subject: Taking Solar Power To New Heights
Date: Sunday, October 22, 2000 9:17 AM
**This is a mailing from the Renewable Energy Online Newsletter**
http://www.webconx.com/thermal.htm
http://www.webconx.com/chimney.htm
http://www.webconx.com/pv.htm
Taking Solar Power To New Heights
----------------------------------------------------------------------------
----
Story Filed: Friday, October 20, 2000 1:50 PM EST
Johannesburg (Mail and Guardian, October 20, 2000) - The downside is, South
Africa is one of the world's top 20 polluters. At least 93,5% of South
African electricity is coal-fired.
Eskom is the world's single largest producer of carbon dioxide. Acid rain
created by power stations causes fences near Bethel to disintegrate in just
three years.
The upside? Southern Africa receives 59% of the world's highest quality
sunshine. The Northern Cape government hopes to build the world's largest
solar- power station near Sishen, following a revolutionary design.
Eskom is planning the largest solar-only thermal power plant.
Solar panels or photovoltaic cells (PVs), which directly convert sunlight
into electricity, tend to be the most widely known solar technology.
Already, there are large numbers of solar panels in use in schools and rural
communities in South Africa. Telecommunications companies use them to power
remote installations, such as microwave stations.
In 1998 Eskom and Shell embarked on an ambitious joint venture in the
Eastern Cape to provide solar energy to 50 000 households. The concept uses
charge cards, which cost about R40 a month. The installations provide
sufficient power to run a couple of light bulbs, or a TV set.
However, there have been problems. People often consider anything other than
grid power second-rate.
But Shell's Koosum Kalyan says acceptance is growing, and more than 6 000
units have been installed. A small industry is growing around maintenance of
the units and the sale of magnetic cards needed to run them.
Professor Dieter Holm of the University of Pretoria contributed to a recent
study commissioned by the Department of Housing to examine ways of making
low- cost housing more energy efficient.
Holm, who is also a member of the International Solar Energy Society, firmly
believes that only houses that are properly oriented to face north should
actually receive housing subsidies. Assuming the roof is constructed at the
right pitch (the dwelling's latitude plus 10 degrees), it then becomes
extremely simple to attach - or even build into the roof - a solar water
heater and photovoltaic power unit.
Similarly, solar thermal co- generating installations could be placed on the
roofs of factories. Solar thermal plants use the sun's heat to create steam,
which then drives a generator.
In a co-generating installation, rather than going directly into electricity
generation, some of that steam is used directly in the manufacturing process
as "process heat" (for baking, pasteurisation, drying and the like).
The idea of building energy generation right into a building is already
catching on in Europe, despite its far lower levels of sun- light than South
Africa. The declining cost of PVs means that they can be incorporated into
building facades. During the day elec- tricity consumers can then sell power
back into the grid, offsetting their night-time bills. Unfortunately, on
large scales, PVs are too expensive to be practical and designers are
considering a multitude of other options.
Should the ambitions of the Northern Cape bear fruit, within a few years an
extraordinary structure could rise from the arid, sun-baked land near
Sishen - a chimney 1,5km high, nearly 200m wide and surrounded by a
greenhouse about 7km in diameter. Air heated under the glass would be drawn
up through the chimney, accelerating to drive a wind turbine located at its
base.
This R4-billion project would produce 400MW of electricity. Koeberg, by
contrast, produces 1900MW, or 4,5% of Eskom's total production.
The efficiency, both physical and financial, of the solar chimney will be
increased by using the greenhouse for cultivation, according to project
manager Wolf Stinnes.
The productivity of the soil will be increased by using humus, which is
highly water retentive. The physical effect of having a large amount of
water under the greenhouse will be to create a mass capable of heat storage.
At night this heat will be released, allowing the chimney to operate 24
hours a day.
Experiments with a 200m prototype solar chimney at Manzanares in Spain
showed that cultivation within the greenhouse reduced heat losses,
increasing the chimney's energy efficiency. Stinnes expects the cultivated
land, which will amount to 25 square kilometres, to be so productive that
"we could give the electricity away".
Since the Northern Cape is one of the world's most seismologically stable
areas, the alarming notion of a 1,5km-high chimney wobbling - or worse - in
such an event can be ruled out.According to Stinnes, its proposed height is
not as outrageous as it seems - Japanese architects are considering 2km-high
skyscrapers for earthquake-prone Tokyo.
Fortunately, the Northern Cape is also free of the hailstorms that would
make a 6,5km wide greenhouse rather impractical.
Though the construction would be directed by a German company, Concor, LTA,
Group 5 and Stocks & Stocks have all tendered for the actual construction.
Eskom says it is concerned that a jump from a 200m prototype solar chimney
to a 1 500m commercial version is overly ambitious. It is considering
various other solar thermal technologies.
Eskom's renewable energy project leaders, Louis van Heerden and Kevin
Nassiep, point out that these technologies, unlike the solar chimney, have
been endorsed by the Global Environment Facility, a renewable
energies-funding mechanism run by the World Bank and the United Nations.
Eskom's solar thermal interests centre on three possible designs: solar
troughs, central receivers and Stirling/dish reflectors. Solar troughs are
long reflective troughs, with a parallel thin pipe running through the focal
point. The reflectors concentrate heat on the pipes, heating oil that is in
turn used to generate electricity. The trough tilts slowly through the day
to follow the sun.
The central receiver design has a heat collector mounted on a tower. The
tower is surrounded by circular ranks of mirrors, which track the sun
through the day and reflect it on to the collector. Air or molten salt in
the tower accumulates the heat, which is then used, as in a conventional
power station, to create steam to drive a turbine. The molten salt can also
serve to store heat when direct sunlight is not available.
The third option, the parabolic dish, looks like a large, mirrored satellite
dish. Heat is focused on a Stirling engine, a mechanical device that
converts external heat into motion. Eskom is likely to begin installing
Stirling/dish reflectors early in 2001, experimenting with different models.
Though renewable energies are currently far from being as inexpensive as
coal-fueled Eskom power, the provisions of the United Nations Framework
Convention on Climate Change and technological development are soon likely
to make it increasingly practical.
But, as Holm notes, the gap in public awareness of such technologies remains
an obstacle to their widespread adoption. Only when South Africans begin to
turn the heat on to energy suppliers and politicians, is the sun's heat -
one of our most abundant resources - likely to be used rather than ignored.
E-mail the Science editor: belinda@.mg.co.za
Steve Spence
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karljo...@my-deja.com
"Steve Spence" <ssp...@webconx.com> wrote:
>
> From: "Steve Spence" <ssp...@webconx.com>
> To: "Energy - WebConX" <ene...@webconx.com>
> Subject: Taking Solar Power To New Heights
> Date: Sunday, October 22, 2000 9:17 AM
>
> **This is a mailing from the Renewable Energy Online Newsletter**
> http://www.webconx.com/thermal.htm
> http://www.webconx.com/chimney.htm
> http://www.webconx.com/pv.htm
>
> Taking Solar Power To New Heights
>
> ----------------------------------------------------------------------
------
> ----
>
> Story Filed: Friday, October 20, 2000 1:50 PM EST
>
> Johannesburg (Mail and Guardian, October 20, 2000) - The downside is,
South
> Africa is one of the world's top 20 polluters. At least 93,5% of South
> African electricity is coal-fired.
>
> Eskom is the world's single largest producer of carbon dioxide. Acid
rain
> created by power stations causes fences near Bethel to disintegrate
in just
> three years.
Much as I'm not a big fan of acidic precipitation from fossil fuel
consumption: this sounds like a bit of an exageration.
> The upside? Southern Africa receives 59% of the world's highest
quality
> sunshine.
I'm very confused. What is "the world's highest quality sunshine"? How
does one calculate that a given country has 59% of this sunshine?
Facinating idea. SOunds expensive. Pardon my lack of knowledge about
thermodynamics here; if the wind turbine is at the base of the chimney,
why does it have to be 1.5 kilometre high.
Salt is an interesting option. Luz used therminol & that's what lead to
the explosion there.
> The third option, the parabolic dish, looks like a large, mirrored
satellite
> dish. Heat is focused on a Stirling engine, a mechanical device that
> converts external heat into motion. Eskom is likely to begin
installing
> Stirling/dish reflectors early in 2001, experimenting with different
models.
>
> Though renewable energies are currently far from being as inexpensive
as
> coal-fueled Eskom power, the provisions of the United Nations
Framework
> Convention on Climate Change and technological development are soon
likely
> to make it increasingly practical.
>
> But, as Holm notes, the gap in public awareness of such technologies
remains
> an obstacle to their widespread adoption. Only when South Africans
begin to
> turn the heat on to energy suppliers and politicians, is the sun's
heat -
> one of our most abundant resources - likely to be used rather than
ignored.
>
> E-mail the Science editor: belinda@.mg.co.za
>
> Steve Spence
Karl Johanson
Sent via Deja.com http://www.deja.com/
Before you buy.
Scott Willing
says...
> > Should the ambitions of the Northern Cape bear fruit, within a few
> years an
> > extraordinary structure could rise from the arid, sun-baked land near
> > Sishen - a chimney 1,5km high, nearly 200m wide and surrounded by a
> > greenhouse about 7km in diameter. Air heated under the glass would be
> drawn
> > up through the chimney, accelerating to drive a wind turbine located
> at its
> > base.
>
> Facinating idea. SOunds expensive. Pardon my lack of knowledge about
> thermodynamics here; if the wind turbine is at the base of the chimney,
> why does it have to be 1.5 kilometre high.
Oh heck, you're smarter than that Karl. I suppose your house is heated by
nuclear generated electricity, 'cos if you had a woodstove you'd have
some intuitive understanding of DRAW.
Here's my non-thermodynamically educated idiot's take: It's a solar-
heated chimney. The taller it is the better it should draw. Since it's
also the heat collector, the taller it is the more heat it can collect.
Finally, it's a pipe with air moving through it. Presumably the same
breeze comes out the top as goes in the bottom, so what does it matter
where the turbine is? Except of course, that it would be a !@#$ of a lot
easier to build it at the bottom, n'est pas?
So BTW, is Victoria still dumping your untreated turds into the ocean?
--
Scott Willing
karljo...@my-deja.com
wil...@mb.sympatico.ca (Scott Willing) wrote:
> In article <8svboq$c5c$1...@nnrp1.deja.com>, karljo...@my-deja.com
> says...
> > years an
> > > extraordinary structure could rise from the arid, sun-baked land
near
> > > Sishen - a chimney 1,5km high, nearly 200m wide and surrounded by
a
> > > greenhouse about 7km in diameter. Air heated under the glass
would be
> > drawn
> > > up through the chimney, accelerating to drive a wind turbine
located
> > at its
> > > base.
> >
> > Facinating idea. SOunds expensive. Pardon my lack of knowledge about
> > thermodynamics here; if the wind turbine is at the base of the
chimney,
> > why does it have to be 1.5 kilometre high.
>
Thank you. I still don't know the answer though.
>I suppose your house is heated by
> nuclear generated electricity, 'cos if you had a woodstove you'd have
> some intuitive understanding of DRAW.
I have a fire place, an oil heater & some portable electric heaters
(mostly hydro & some natural gas makes the electricity here). No, I
don't understand draw. I'd be happy if you explained the roll of a
chimney in draw. Thanks.
> Here's my non-thermodynamically educated idiot's take: It's a solar-
> heated chimney.
Well, there's where I didn't completely get it. My understanding was
that the heat was gathered by the 25 square kilometer greenhouse at the
bottom, not from the chimney. I still don't follow. As I said, I'm not
the world expert on thermodynamics.
>The taller it is the better it should draw. Since it's
> also the heat collector, the taller it is the more heat it can
collect.
> Finally, it's a pipe with air moving through it. Presumably the same
> breeze comes out the top as goes in the bottom, so what does it
matter
> where the turbine is? Except of course, that it would be a !@#$ of a
lot
> easier to build it at the bottom, n'est pas?
My French isn't all that good either. At the bottom of the chimney does
sound cheaper & easier. Once I understand draw I'll probably get why
you need the chimney as well.
> So BTW, is Victoria still dumping your untreated turds into the ocean?
Victoria has treated it's sewage for some time now. It doesn't have
toxic chlorine compounds added to it, but it is treated. Some argue
that it should have additional treatment as well. I don't know enough
about it to say for sure one way or the other. Victoria concentrates on
keeping industrial chemicals out of it's sewage. The thought is that
it's easier to keep chemicals out of the sewage than to try to remove
them afterwards. I have to agree on that one. I've argued on local
radio that all the government buildings should replace their existing
toilets with composting toilets & that we can consider mandating
composting toilets on all new buildings. Less sewage & a source of
usable soil.
I expect you have some reason for thinking this is related to solar
energy. . .
> Scott Willing
Ol' Northwest
>
> In article <MPG.145f65bce...@news.mb.sympatico.ca>,
> wil...@mb.sympatico.ca (Scott Willing) wrote:
> > In article <8svboq$c5c$1...@nnrp1.deja.com>, karljo...@my-deja.com
> > says...
> > > > Should the ambitions of the Northern Cape bear fruit, within a few
> > > years an
> > > > extraordinary structure could rise from the arid, sun-baked land
> near
> > > > Sishen - a chimney 1,5km high, nearly 200m wide and surrounded by
> a
> > > > greenhouse about 7km in diameter. Air heated under the glass
> would be
> > > drawn
> > > > up through the chimney, accelerating to drive a wind turbine
> located
> > > at its
> > > > base.
> > >
> > > Facinating idea. SOunds expensive. Pardon my lack of knowledge about
> > > thermodynamics here; if the wind turbine is at the base of the
> chimney,
> > > why does it have to be 1.5 kilometre high.
> >
> > Oh heck, you're smarter than that Karl.
Carl,
Consider it the reverse of those tall water towers you see in flatland
towns. The taller the tower, the higher the water pressure is at the
bottom.
If you have heated air and gas (expanded hence less dense, as in a
stove chimney) the taller the stack, the greater the force upward... and
the faster it will draw air in at the bottom. Also at 1.5 km high
(who'd build that thing?) the air would be considerably less dense at
the top, which I think would improve the exhaust effect, as in
automotive exhaust extractors.
Now that I think about it, a very tall stack in your backyard with a
very small amount of fuel (e.g. wood) might even turn a turbine enough
to generate some power. If the fan could stand the heat, if the
neighbors would put up with it, if, if...
cheers,
Nelson
Scott Willing
> karljo...@my-deja.com wrote:
> >
> > In article <MPG.145f65bce...@news.mb.sympatico.ca>,
> > wil...@mb.sympatico.ca (Scott Willing) wrote:
> > > In article <8svboq$c5c$1...@nnrp1.deja.com>, karljo...@my-deja.com
> > > says...
> > > > > Should the ambitions of the Northern Cape bear fruit, within a few
> > > > years an
> > > > > extraordinary structure could rise from the arid, sun-baked land
> > near
> > > > > Sishen - a chimney 1,5km high, nearly 200m wide and surrounded by
> > a
> > > > > greenhouse about 7km in diameter. Air heated under the glass
> > would be
> > > > drawn
> > > > > up through the chimney, accelerating to drive a wind turbine
> > located
> > > > at its
> > > > > base.
> > > >
> > > > Facinating idea. SOunds expensive. Pardon my lack of knowledge about
> > > > thermodynamics here; if the wind turbine is at the base of the
> > chimney,
> > > > why does it have to be 1.5 kilometre high.
> > >
> > > Oh heck, you're smarter than that Karl.
>
> Consider it the reverse of those tall water towers you see in flatland
> towns. The taller the tower, the higher the water pressure is at the
> bottom.
> If you have heated air and gas (expanded hence less dense, as in a
> stove chimney) the taller the stack, the greater the force upward... and
> the faster it will draw air in at the bottom. Also at 1.5 km high
> (who'd build that thing?) the air would be considerably less dense at
> the top, which I think would improve the exhaust effect, as in
> automotive exhaust extractors.
> Now that I think about it, a very tall stack in your backyard with a
> very small amount of fuel (e.g. wood) might even turn a turbine enough
> to generate some power. If the fan could stand the heat, if the
> neighbors would put up with it, if, if...
But if the turbine were on the intake, it wouldn't have to handle the
heat, would it?
It's an interesting thought, (the home-brew wood-fired turbine) but I
*suspect* (no qualifications or pretentions thereto) there are probably
more efficient ways of wood-fired electrical generation. Steam perhaps,
though what reading I've done suggests that this isn't too efficient
either.
--
Scott Willing
Ol' Northwest
>
> In article <39F6D5...@mts.net>, ngietz...@mts.net says...
> > karljo...@my-deja.com wrote:
> > >
> > > wil...@mb.sympatico.ca (Scott Willing) wrote:
> > > > In article <8svboq$c5c$1...@nnrp1.deja.com>, karljo...@my-deja.com
> > > > says...
> > > > > > Should the ambitions of the Northern Cape bear fruit, within a few
> > > > > years an
> > > > > > extraordinary structure could rise from the arid, sun-baked land
> > > near
> > > > > > Sishen - a chimney 1,5km high, nearly 200m wide and surrounded by
> > > a
> > > > > > greenhouse about 7km in diameter. Air heated under the glass
> > > would be
> > > > > drawn
> > > > > > up through the chimney, accelerating to drive a wind turbine
> > > located
> > > > > at its
> > > > > > base.
> > > > >
> > > > > Facinating idea. SOunds expensive. Pardon my lack of knowledge about
> > > > > thermodynamics here; if the wind turbine is at the base of the
> > > chimney,
> > > > > why does it have to be 1.5 kilometre high.
> > > >
> > > > Oh heck, you're smarter than that Karl.
> >
> > Consider it the reverse of those tall water towers you see in flatland
> > towns. The taller the tower, the higher the water pressure is at the
> > bottom.
> > If you have heated air and gas (expanded hence less dense, as in a
> > stove chimney) the taller the stack, the greater the force upward... and
> > the faster it will draw air in at the bottom. Also at 1.5 km high
> > (who'd build that thing?) the air would be considerably less dense at
> > the top, which I think would improve the exhaust effect, as in
> > automotive exhaust extractors.
> > Now that I think about it, a very tall stack in your backyard with a
> > very small amount of fuel (e.g. wood) might even turn a turbine enough
> > to generate some power. If the fan could stand the heat, if the
> > neighbors would put up with it, if, if...
>
> But if the turbine were on the intake, it wouldn't have to handle the
> heat, would it?
Scott, I thought of that as I was walking away from the computer after
my last post! LOL
Actually, if you have wood heat, try starting a small fire, then
opening the stove door an inch or so when the flames get going. You may
have to vary it a bit, but at a certain point, watch that sucker DRAW!
I've done it with a fireplace, holding an open sheet of newspaper so it
blocked all but the bottom two inches. Pulled the paper outa my hands
and up the flue. There may yet be some potential here for a backwoods
kind of homebrew generator. A small fan with permanent magnet field,
like a car heater fan, on the intake...
Maybe I should just go and have breakfast!
Nelson
fungee
karljo...@my-deja.com wrote:
> I have a fire place, an oil heater & some portable electric heaters
> (mostly hydro & some natural gas makes the electricity here). No, I
> don't understand draw. I'd be happy if you explained the roll of a
> chimney in draw. Thanks.
Let go of a balloon. It will accellerate until it reaches its terminal
velocity.
If you try to generate energy from heated air, you don't want to let it
out of the chimney too soon, or it will continue to accellerate once it
escapes from the chimney, wasting energy you could have captured.
Of course, you don't want the chimney too long either since you'll get
drag losses at some point.
--
fungee... Unsolicited commercial email (spam) is not desired. Senders
of spam will help me beta test new virii, mailbombs, and/or DoS attacks.
Sending spam to this address constitutes agreement to these terms.
Scott Willing
[shnipped]
> > > Now that I think about it, a very tall stack in your backyard with a
> > > very small amount of fuel (e.g. wood) might even turn a turbine enough
> > > to generate some power. If the fan could stand the heat, if the
> > > neighbors would put up with it, if, if...
> >
> > But if the turbine were on the intake, it wouldn't have to handle the
> > heat, would it?
>
> Scott, I thought of that as I was walking away from the computer after
> my last post! LOL
Doncha hate that?
> Actually, if you have wood heat, try starting a small fire, then
> opening the stove door an inch or so when the flames get going. You may
> have to vary it a bit, but at a certain point, watch that sucker DRAW!
Very familiar with this. Actually learned same from a wood heat web site
when I was struggling with the first wood stove I ever used to any
degree. Short chimney... trying to get the thing going I either had a lot
of smoke indoors (door open) or a fire that went out almost instantly
(door closed). After I learned the "cracked open door" bit, no problems.
(I have a much better stove and chimney now.)
> I've done it with a fireplace, holding an open sheet of newspaper so it
> blocked all but the bottom two inches. Pulled the paper outa my hands
> and up the flue. There may yet be some potential here for a backwoods
> kind of homebrew generator. A small fan with permanent magnet field,
> like a car heater fan, on the intake...
It really is an interesting idea. One of the catalogues I have includes a
(propane-fired) heater that generates up to 100W of electricity too,
using - get this - IR-sensitive PV(!) When I first saw it, I thought "100
Watts? So what?" but then I got to thinking... hmm, 100W is nothing to
sneer at, especially (for a solar-powered guy like me) if you can get it
in the dark as a byproduct of heating.
> Maybe I should just go and have breakfast!
You can never go wrong with breakfast.
-s
George Estep
I've been wanting to do this with my pellet stove to try to improve my
energy balance in the winter. I would appreciate any information which you
can provide pointing me regarding a manufacturer of IR PV panels. After
all, 100 W is 2.4 kWh/day!
Just information on the propane-fired heater would be a good start!
Thanks in advance,
George
"Scott Willing" <wil...@mb.sympatico.ca> wrote in message
news:MPG.14624c3b2...@news.mb.sympatico.ca...
> In article <39F822...@mts.net>, ngietz...@mts.net says...
> [shnipped]
>
Scott Willing
says...
> Hi Scott,
>
> I've been wanting to do this with my pellet stove to try to improve my
> energy balance in the winter. I would appreciate any information which you
> can provide pointing me regarding a manufacturer of IR PV panels. After
> all, 100 W is 2.4 kWh/day!
Well, that's "roughly" 100W and that's peak - don't forget you're dumping
heat into the room and burning fuel to do it. But I hear ya brother, like
I said, it's nothing to sneer at.
> Just information on the propane-fired heater would be a good start!
That'll have to do, since that's all I know. (Should've posted it in the
first place - it was bound to pique some interest, yeah?)
The supplier is Backwoods Solar Electric Systems (an EXcellent crew, by
the way, very helpful, amazing service and support -- and I'm a long way
from where there are in Sandpoint Idaho). www.backwoodssolar.com
The heater is the Midnight Sun, a 25,000 BTU unit that generates up to
8A@12V or 4A@24V. It ain't cheap, but then (to my knowledge) it's a
pretty unique product. Apparently developed in Norway, where they run a
little short of sun in the winter, y'know? A quick web search didn't turn
up a lot.
I would imagine it would be a lot harder to use the IR PV concept with
solid fuels, which is too bad. I have two propane appliances now and I'm
keen to get rid of them, rather than buy more. It'll be real interesting
to see if this technology is further developed. I didn't find much from a
web search on IR-sensitive PV, but I didn't try very hard.
Good luck, let us know if you find anything.
Cheers,
-s
fungee
"George Estep" <gke...@shentel.net> wrote:
> Hi Scott,
>
> I've been wanting to do this with my pellet stove to try to
improve my
> energy balance in the winter. I would appreciate any information
which you
> can provide pointing me regarding a manufacturer of IR PV panels.
After
> all, 100 W is 2.4 kWh/day!
Not a good idea for me. Electricity is 6 cents per kWh, including tax.
Even if I could use the thing 24 hours/day for 120 days per year, that
would save me $17.28. How long would it take to pay for itself? 6%
interest on $300 is $18.00, so possibly never.
--
fungee... Unsolicited commercial email (spam) is not desired. Senders
of spam will help me beta test new virii, mailbombs, and/or DoS attacks.
Sending spam to this address constitutes agreement to these terms.
George Estep
I'm not sure why this would not be useful for solid fuels. My pellet
stove can put out as much as 61,000 BTU/hr. If I could generate 100 watt at
peak output, that would be great. My thought is to have one panel facing
each of the two sides of the stove, where the temperature appears to be
hottest on the outside. I don't think inside would work because of all of
the smoke and ash.
I will check this out!
George
"Scott Willing" <wil...@mb.sympatico.ca> wrote in message
news:MPG.1463502cf...@news.mb.sympatico.ca...
George Estep
George
"fungee" <fun...@my-deja.com> wrote in message
news:8tc7h6$os4$1...@nnrp1.deja.com...
fungee
"George Estep" <gke...@shentel.net> wrote:
> You PAY for electricity? I bet you PAY for water, too! ;-)
Yep. Everyone pays. Even if you use a exerciser to turn a generator or
a hand-pump to pump H2O from a well.
Actually, I guess some people don't pay. But they get their service cut
off. :-)
MorEl
> rain
> > created by power stations causes fences near Bethel to disintegrate
> in just
> > three years.
>
> Much as I'm not a big fan of acidic precipitation from fossil fuel
> consumption: this sounds like a bit of an exageration.
Doesn't sound like that to me....
Just try sitting in your closed garage with your cars engine turned on for a
couple of hours :)
>
> > The upside? Southern Africa receives 59% of the world's highest
> quality
> > sunshine.
>
> I'm very confused. What is "the world's highest quality sunshine"? How
> does one calculate that a given country has 59% of this sunshine?
Meaning that:
1) 59% = that is the energy that can be used from the 100% of energy that
the Sun sends thru the whole year.
2) Highest quailty, meaning that the energy reaching the surface has not
gone thru any radical changes (remember why the sky has the color of blue?)
meaning wavelength and such.
> > Should the ambitions of the Northern Cape bear fruit, within a few
> years an
> > extraordinary structure could rise from the arid, sun-baked land near
> > Sishen - a chimney 1,5km high, nearly 200m wide and surrounded by a
> > greenhouse about 7km in diameter. Air heated under the glass would be
> drawn
> > up through the chimney, accelerating to drive a wind turbine located
> at its
> > base.
>
> Facinating idea. SOunds expensive. Pardon my lack of knowledge about
> thermodynamics here; if the wind turbine is at the base of the chimney,
> why does it have to be 1.5 kilometre high.
Well... In order to understand this, remeber how winds are made in the first
place.
Different air pressure.
So, when you make a chimeny, the air goes out the top of the chimney -
creating an area of lower pressure behind - which makes the air on the other
end of the chimney (where the pressure is higher) go in.
So the point would be that the air in the chimeny goes out because it is
warm - so it goes higher.
That makes the air on the bottom of the chimney go in faster.
So the above concept would work even if there was no greenhouse.
The role of the greenhouse is two things:
1) Increase the pressure of the air beneath the chimeny even moe, thus
creating even faster flow - meaning more energy.
2) When the sun goes down, the air inside is still warm, so the chimeny
keeps working - albeit with a decreased capacity.
Now, if the chimney is too short, the heat exchange (air in the chimney -
air outside of the chimney) will happen too soon for there to be any usable
flow (it will be too non-linear, and too slow)
If the chimney is too long, on the other hand, the air pressure at the high
end will be much lower, and the turbulence caused by the air inside the
chimney will cause losing of additional speed of the flow, thus causing
energy losses - so the energy production will again be lowered.
> Karl Johanson
Steve Spence
--
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--
"George Estep" <gke...@shentel.net> wrote in message
news:svjfucn...@corp.supernews.com...
Steve Spence
but you are forgetting the heat output you are getting. don't try to figure
payback on electrical generation alone.
--
Steve Spence
Subscribe to the Renewable Energy Newsletter:
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We do not inherit the earth from our ancestors,
we borrow it from our children.
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"fungee" <fun...@my-deja.com> wrote in message
news:8tc7h6$os4$1...@nnrp1.deja.com...
RHolb99180
>> > The upside? Southern Africa receives 59% of the world's highest
>> quality
>> > sunshine.
Must be the ozone hole?
George Estep
I'm not buying it. Higher temperatures will radiate more. I'm sure
output power is related to temperature.
George
"Steve Spence" <ssp...@webconx.com> wrote in message
news:x6BK5.90298$ib7.12...@news1.rdc1.nj.home.com...
Steve Spence
infrared, not heat.
--
Steve Spence
Subscribe to the Renewable Energy Newsletter:
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(212) 894-3704 x3154 - voicemail/fax
We do not inherit the earth from our ancestors,
we borrow it from our children.
--
"George Estep" <gke...@shentel.net> wrote in message
news:svp7ljm...@corp.supernews.com...
Ol' Northwest
Guys,
It occurs to me that an IR panel could be installed over the glass
faceplate on some stove doors... there's a whack of radiant heat coming
out of there, far more than off the sides of the one I have.
Incidentally, I just installed 200W of PV panels on my "new" system, to
keep the batteries up through the winter until I can get the rest of the
panels and wind turbine up in the Spring. I've been tracking
consumption at the little place in the backwoods during the last two
weekends. Using 20W flourescents in place of the four most
commonly-used lights, an electric blanket for a couple of hours the
first night, 600 watts (that'll change) of outside lighting when
necessary to fill the woodbin, a toaster and small microwave as
needed... total weekend consumption is no more than about 65 amp hours,
and I don't feel we're pinching.
Battery bank is 24V. The panels are delivering at most a 9A charge
(saw that once), mostly about 5A, and it seems even with about 50%
cloud, they can make up most of the previous night's consumption.
Bottom line is, in the cold season, a good IR installation delivering
4A on a solid fuel stove could provide a big part of the required
energy.
Cheers,
Nelson
P.S. I haven't fired up the generator for three weeks. Boy, does that
feel good!
George Estep
Are you trying to say that my pellet stove does not radiate infrared?
And that the amount of infrared radiated is not dependent on temperature
differentials?
If so, I would have to disagree with you. Having designed and tested
spacecraft equipment, I have seen first hand the effects of infrared
radiation on component temperatures. It's quite impressive in space,
because items which aren't very warm are radiating significant energy into
space due to the fact that they are staring at -160 degrees (IIRC) Celsius!
George
"Steve Spence" <ssp...@webconx.com> wrote in message
news:hL5L5.93572$ib7.13...@news1.rdc1.nj.home.com...
fungee
"Steve Spence" <ssp...@webconx.com> wrote:
> you are lucky, we pay .12 / kwh
>
> but you are forgetting the heat output you are getting. don't try to
figure
> payback on electrical generation alone.
Ah yes. Major blunder.
Steve Spence
light has to be of the frequency the panel is designed for.
--
Steve Spence
Subscribe to the Renewable Energy Newsletter:
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We do not inherit the earth from our ancestors,
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--
"R.H. Allen" <kka...@hotmail.com> wrote in message
news:1aqrvsgm1j1o3clri...@4ax.com...
> On Mon, 30 Oct 2000 06:53:40 -0500, "George Estep"
> <gke...@shentel.net> wrote:
>
> >Hi Steve,
> >
> > Are you trying to say that my pellet stove does not radiate infrared?
> >And that the amount of infrared radiated is not dependent on temperature
> >differentials?
>
> If I'm not mistaken, the amount of IR radiated by your stove is
> related to the absolute temperature, not to temperature differentials.
> And what Steve is saying is that you can't just slap any old
> thermophotovoltaic (TPV) panel against your stove and expect to get
> energy -- the materials that TPV panels are made of convert different
> wavelengths more efficiently than others, just like regular solar
> cells. The panels must be matched to a particular temperature/IR
> spectrum for them to work well.
>
> >> > I'm not buying it. Higher temperatures will radiate more. I'm
sure
> >> > output power is related to temperature.
>
> I agree with you there. Higher temperatures will generally produce
> more IR radiation unless the radiating body is nothing at all like a
> blackbody. But whether or not a given IR photon can be efficiently
> converted into electricity depends on its wavelength and the TPV panel
> in question.
>
> >> > > > I'm not sure why this would not be useful for solid fuels.
My
> >> > pellet
> >> > > > stove can put out as much as 61,000 BTU/hr. If I could generate
100
> >> > watt
> >> > > at
> >> > > > peak output, that would be great. My thought is to have one
panel
> >> > facing
> >> > > > each of the two sides of the stove, where the temperature appears
to
> >> be
> >> > > > hottest on the outside. I don't think inside would work because
of
> >> all
> >> > of
> >> > > > the smoke and ash.
>
> I don't think outside will work -- it just won't be hot enough. You
> might get a little energy production, but it won't be much. TPVs are
> usually installed inside very clean-burning furnaces. Even then, I'm
> not sure what kinds of efficiencies they get.
>
> >> > > > I will check this out!
>
> By all means do -- if you prove me wrong I'll be glad to hear it!
George Estep
This discussion was about infrared PV, not standard PV. I'm not too
concerned about efficiency, but rather how much electricity I can generate
and at what cost. I can only do this if I have specifications for a product
I can buy. Clearly products exist, because they are used in the stove Scott
mentioned. Does anyone know where I can buy them?
George
P.S. I do remember from spacecraft testing that the cooling due to
radiation from a body in space was related to the temperature it "saw".
Hence, in order to test spacecraft, it was necessary to place a
temperature-controlled device around the UUT and lower it's temperature to
match that of space in order to duplicate the environment. Perhaps
radiation is based on absolute temperatures, but the problem is that the
receiver will radiate as well, making the net cooling lower.
"Steve Spence" <ssp...@webconx.com> wrote in message
news:VQrL5.95671$ib7.13...@news1.rdc1.nj.home.com...
George Estep
I appreciate your help with this. I will try to contact the
manufacturer of the stove to find out where they get the panels from. Then
I will try to get specs and pricing from the manufacturer. I should be able
to estimate the radiation from the stove using the black body equation and
temperature measurements. If it's not overly expensive, it may be worth
investigating. Note that the cost of the stove is not much more than a
high-end pellet stove.
Again, I appreciate your taking time to explain this in some detail.
Regards,
George Estep
"R.H. Allen" <kka...@hotmail.com> wrote in message
news:66buvsgodptllubse...@4ax.com...
> On Tue, 31 Oct 2000 07:48:53 -0500, "George Estep"
> <gke...@shentel.net> wrote:
>
> >Hi Guys,
> >
> > This discussion was about infrared PV, not standard PV. I'm not too
> >concerned about efficiency, but rather how much electricity I can
generate
> >and at what cost. I can only do this if I have specifications for a
product
> >I can buy. Clearly products exist, because they are used in the stove
Scott
> >mentioned. Does anyone know where I can buy them?
>
> Unfortunately I don't know where you can buy TPV cells, nor do I know
> their costs. I suspect that they aren't cheap, since the are often
> made of somewhat exotic materials, but I'm really not familiar with
> the commercial TPV market so I can't say for sure. I still maintain
> that they're unsuitable for a wood-burning stove, though -- you'll
> notice that the stove Scott mentioned burns propane. I'd be very
> surprised if you got usable amounts of power placing the panels on the
> outside of the stove.
>
> >P.S. I do remember from spacecraft testing that the cooling due to
> >radiation from a body in space was related to the temperature it "saw".
> >Hence, in order to test spacecraft, it was necessary to place a
> >temperature-controlled device around the UUT and lower it's temperature
to
> >match that of space in order to duplicate the environment. Perhaps
> >radiation is based on absolute temperatures, but the problem is that the
> >receiver will radiate as well, making the net cooling lower.
>
> Absolutely, the temperature difference is critical when you're talking
> about cooling -- with no temperature difference there is no cooling.
> It's also true that hot TPV panels may well do some radiating of their
> own (and they may also recapture some of their own radiation before it
> escapes -- a phenomenon known as photon recycling). But the electrical
> energy produced by the TPV cells still comes purely from absorbing
> photons in the proper range of wavelengths. The absolute temperature
> of the panel might affect performance, but its temperature relative to
> some other object has no bearing on it.
Duane C. Johnson
George Estep <gke...@shentel.net> wrote:
> I appreciate your help with this. I will try to
> contact the manufacturer of the stove to find out
> where they get the panels from. Then I will try
> to get specs and pricing from the manufacturer.
> I should be able to estimate the radiation from the
> stove using the black body equation and temperature
> measurements. If it's not overly expensive, it may
> be worth investigating. Note that the cost of the
> stove is not much more than a high-end pellet stove.
> George Estep
Are you sure the stove uses ThermoPhotoVoltaic, TPV, cells
and not ThermoElectric, TE, cells.
The TE devices operate on temperature differences and are
the inverse of the thermal cooler technology that is mass
produced for refrigeration. They are also fairly cheap.
TE cells generate a fair amount of power at low efficiencies.
However, the low efficiency is not a problem as the waste
heat is used to heat the room and not wasted.
Duane
--
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These are my opinions, and not that of Unisys Corp. ===
George Estep
No, I'm not sure of anything, since I haven't been able to track down
the source. However, the web site does say that this furnace uses infrared
PV:
http://www.backwoodssolar.com/Catalogpages2/gen2.htm#MIDNIGHT%20SUN
George
"Duane C. Johnson" <red...@redrok.com> wrote in message
news:3A001538...@redrok.com...
dst...@dakotacom.net
>
> Hi Duane,
>
> No, I'm not sure of anything, since I haven't been able to track down
> the source. However, the web site does say that this furnace uses infrared
> PV:
>
> http://www.backwoodssolar.com/Catalogpages2/gen2.htm#MIDNIGHT%20SUN
>
http://www.eastsidejournal.com/ejbiz_archive/jfb31646.html
http://www.jxcrystals.com/profile.htm
Found these two with a quick search. No real data, just "our special
infrared cells generate one hundred times more power per unit area than
solar cells". Nothing about operating temps, spectrum, output, etc. But
the Jxcrystals seem to be the manufacture. Maybe our solar concentrators
will finally have something to heat up now.
David
dst...@dakotacom.net
design and claims of 8% conversion efficiency.
David
Nick Pine
>...I should be able to estimate the radiation from the stove using
>the black body equation and temperature measurements.
Sure. At 600 F (589 K) it will radiate about 5.67x10^-8(589^4-R293^4)
= 6.4 kW/m^2 to a 68 F (293 K) room. The max power occurs at 2898/589
= 4.92 microns, and the power density at temp T (K) and wavelenth L
is 3.74x10^8/(exp((1.44x10^4)/(LT))-1), eg 908 W/m^2-um at 4.92 um.
>If it's not overly expensive, it may be worth investigating.
But it probably is...
Nick
Robert Scott
Willing) wrote:
>In article <svj11ht...@corp.supernews.com>, gke...@shentel.net
>says...
>> Hi Scott,
>>
>> I've been wanting to do this with my pellet stove to try to improve my
>> energy balance in the winter. I would appreciate any information which you
>> can provide pointing me regarding a manufacturer of IR PV panels. After
>> all, 100 W is 2.4 kWh/day!
>
>Well, that's "roughly" 100W and that's peak - don't forget you're dumping
>heat into the room and burning fuel to do it. But I hear ya brother, like
>I said, it's nothing to sneer at.
Well, let's see. If you run this 100 PW 24 hours a day you get
2.4 kW-Hr. At 10 cents per kW-Hr, that comes to 24 cents per day.
Robert Scott
Ann Arbor, Michigan (rscott {at sign} wwnet {period} net is my real email address.)
(My automatic return address is intentionally invalid to foil spammers.)
George Estep
I got two links in the first message, but did you mean to include one here,
as well?
Thanks again,
George
<dst...@dakotacom.net> wrote in message news:3A003C...@dakotacom.net...
pms...@hathor.dera.gov.uk
Duane C. Johnson <red...@redrok.com> wrote:
>
>Are you sure the stove uses ThermoPhotoVoltaic, TPV, cells
>and not ThermoElectric, TE, cells.
>
>The TE devices operate on temperature differences and are
>the inverse of the thermal cooler technology that is mass
>produced for refrigeration. They are also fairly cheap.
>
>TE cells generate a fair amount of power at low efficiencies.
>However, the low efficiency is not a problem as the waste
>heat is used to heat the room and not wasted.
>
Any reason not to use both? Apart from the usual one of cost, of course.
Scott Willing
I suspect everyone on this thread knows what grid power costs in their
particular area -- assuming it is accessible to them, assuming they want
it, etc.
So is there some subtle bit of insightful illumination in your post that
I'm simply too thick to perceive, or have you just restated the obvious
for no useful reason to a bunch of people who obviously don't care?
--
Scott Willing
In article <3a007393...@news.wwnet.net>, see_...@dk37cv.com says...
Robert Scott
Willing) wrote:
>Robert,
>
>I suspect everyone on this thread knows what grid power costs in their
>particular area -- assuming it is accessible to them, assuming they want
>it, etc.
>
>So is there some subtle bit of insightful illumination in your post that
>I'm simply too thick to perceive, or have you just restated the obvious
>for no useful reason to a bunch of people who obviously don't care?
Yes, perhaps I should have been more explicit. I was questioning
the cost effectiveness of the device that generates only 2.4 kw-hr
per day and that only if you run your stove continuously, which
is fine if you were going to do it anyway for heat. But I suspect
that the IR PV device will not pay for itself within its lifetime.
Scott Willing
> On Thu, 2 Nov 2000 11:03:51 -0600, wil...@mb.sympatico.ca (Scott
> Willing) wrote:
>
> >Robert,
> >
> >I suspect everyone on this thread knows what grid power costs in their
> >particular area -- assuming it is accessible to them, assuming they want
> >it, etc.
> >
> >So is there some subtle bit of insightful illumination in your post that
> >I'm simply too thick to perceive, or have you just restated the obvious
> >for no useful reason to a bunch of people who obviously don't care?
>
> Yes, perhaps I should have been more explicit. I was questioning
> the cost effectiveness of the device that generates only 2.4 kw-hr
> per day and that only if you run your stove continuously, which
> is fine if you were going to do it anyway for heat. But I suspect
> that the IR PV device will not pay for itself within its lifetime.
It all depends on your frame of reference. It also depends on where mass-
distribution energy costs might go over the lifetime of the device.
I'm consuming less than 60W at the moment to run all the electrical stuff
I need. I'm far removed, physically, financially and philosophically,
from grid power.
I find TPV an interesting technology and a worthy subject for these
newsgroups, where (I would hope) things don't necessarily have to be
economically competitive (yet) or even practical (yet) to be discussed.
That said, if the Midnight Sun stove ran on solid fuel, I'd already have
ordered one.
--
Scott Willing
sno
Since the energy to produce is included in the cost
of the panel...if you save more then the cost...at
normal electric rates....over life of panel...then
you have a net energy gain.....have to include
inflation and cost of money...(interest you could
get, if you did not spend).....steve
Scott Willing wrote:
>
> Robert,
>
> Clearly the subject of PV energy payback is open to debate, since a
> number of posters have presented data that completely contradicts your
> assertion that they represent a net energy cost outside of special
> applications.
>
> The ordinary citizen is left to guess what the truth might be, as
> boosters and detractors grind their respective axes, present their
> coloured data, and attempt to advance their own overt or covert agendas.
>
> It would be nice to know what the truth is, but it's clear that no source
> can be trusted absolutely, particularly where money is involved. And when
> it comes to energy, a LOT of money is involved.
>
> I put faith in claims in pretty much inverse proportion to how much cash
> is on the line. I think this is a pretty safe policy, since especially in
> North America, many people are apparently incapable of conceiving any
> higher principle or metric than the almighty dollar. If that wasn't bad
> enough, they tend to be pretty selective and simplistic in their choice
> of factors to include in any given equation.
>
> *On both sides of any argument.*
>
> Cheers,
> -smw
>
> In article <3a02d82a...@news.wwnet.net>, see_...@dk37cv.com
> says...
> > I agree with most of what you say. I too am a supporter of
> > alternative energy and have invested in some experiments along
> > those lines. And while I don't ask that solar energy be
> > economically competitive yet, and I certainly don't want to
> > stifle discussion, I think some discussion of cost-effectiveness
> > is in order.
> >
> > In particular, it seems there are lots of good applications for
> > solar energy that are cost-effective or nearly so right now. Direct
> > space heating is the prime candidate. On the other hand, photovoltaic
> > is currently in such a state of development that the energy required
> > just to manufacture a bank of PV cells is greater than the total
> > energy that bank of cells can possibly produce in their lifetime
> > (they do degrade with use). No amount of shifting economic
> > paradigms can alter that fact. So currently if you use PV cells
> > you are wasting energy.
> >
> > The best use of PV cells is not to save on energy costs but to
> > provide convenient power in remote locations where the utilities
> > are not available - such as on your boat or for temporary
> > highway signs - or remote communication stations. Too much
> > emphasis on PV technology as an energy saver can discredit the
> > whole alternative energy movement by distracting attention
> > from the really useful applications. If you want to generate
> > electricity from renewable energy, consider wind or ocean waves.
> > But don't pretend that PV is any kind of an energy saver.
W Bradford Tittle
many might suspect. PV manufacturers have to recoup their costs of
production. As the .coms are discovering, they have to make money in order
to stay in existence. If they do not, they get shut down. Using the price
of a PV panel is as reasonable a method of determining its costs (both
fiscal and environmental) as any other.
I would love to cover my roof in PV panels, but the expense cannot be
justified using the principles of Time Value of Money. Money may be evil in
some peoples eyes, but it allows the free flow of commerce without the
baggage of barter. It also allows decision making to be streamlined. We can
create analyses that weigh the costs and benefits of just about any
decision. The benefits of money far outweigh its bad rap.
If anyone lives close to a Manufacturer of PV panels, we can get a hint of
the power requirements for PV production. How many square feet of PV panels
does the plant have on its roof. If the power needs of the production
facility can be met by the PV cells on the roof, then the net external
energy needed by company decreases. Call the local Power company. I think
that you can get power consumption information about Public Corporations.
It is hard to find the truth in a lot of things these days. The politicians
twist everything to suit their policies. The media sells ad space. The
more we share and the more people that share the better we will be as a
populace. Education is the most important thing we can provide ourselves
and our children.
TNT
Brad Tittle
----------
>> In article <3a02d82a...@news.wwnet.net>, see_...@dk37cv.com
>> says...
>> > I agree with most of what you say. I too am a supporter of
>> > alternative energy and have invested in some experiments along
>> > those lines. And while I don't ask that solar energy be
>> > economically competitive yet, and I certainly don't want to
>> > stifle discussion, I think some discussion of cost-effectiveness
>> > is in order.
>> >
>> > In particular, it seems there are lots of good applications for
>> > solar energy that are cost-effective or nearly so right now. Direct
>> > space heating is the prime candidate. On the other hand, photovoltaic
>> > is currently in such a state of development that the energy required
>> > just to manufacture a bank of PV cells is greater than the total
>> > energy that bank of cells can possibly produce in their lifetime
>> > (they do degrade with use). No amount of shifting economic
>> > paradigms can alter that fact. So currently if you use PV cells
>> > you are wasting energy.
>> >
>> > The best use of PV cells is not to save on energy costs but to
>> > provide convenient power in remote locations where the utilities
>> > are not available - such as on your boat or for temporary
>> > highway signs - or remote communication stations. Too much
>> > emphasis on PV technology as an energy saver can discredit the
>> > whole alternative energy movement by distracting attention
>> > from the really useful applications. If you want to generate
>> > electricity from renewable energy, consider wind or ocean waves.
>> > But don't pretend that PV is any kind of an energy saver.
>> >
>> >
Dlehmicke
>justified using the principles of Time Value of Money.
Do these principles justify the purchase of a Lexus, of orthodonture for your
children, or your choice of present employment when many other jobs or careers
would pay you much more money? What principles justify those decisions? Can
any of those principles justify the expense of PV?
>How many square feet of PV panels
>does the plant have on its roof. If the power needs of the production
>facility can be met by the PV cells on the roof, then the net external
>energy needed by company decreases.
Let's say it takes 10 million kWh annually with a 2-MW demand to produce 1 MW
of PV modules per year (this is in the ballpark based on my experience in a
40,000 square foot PV plant using 4 million kWh annually with an 800-kW demand
to manufacture 350 kW of PV modules). That 1 MW of produced PV will pay back
the 10 million kWh in 10,000 hours of one-sun operation, about 7 years (plus
the time to payback energy for the glass, plastic j-box, manufacturing
equipment, building, workers' clothes, covered wagons, the Mayflower, the ink
on the Magna Carta, the Rosetta Stone, etc.)
The 6 MW of PV needed to operate the plant would require 600,000 square feet of
roof space, whereas the plant is 120,000 square feet (probably smaller, as the
plant in my experience had more than half its space - and a significant
fraction of its energy - dedicated to R&D and equipment manufacture.)
But if you had the roof (or ground) space, 6 MW of PV could provide the energy
required for the manufacture of at least 20 MW of PV, because the 6 MW of PV is
expected to operate for 20 years.
BTW, when you're doing your TVM calcs, be sure to consider that California
allows net metering PV/wind customer/generators to sell at TOU rates starting
1/1/01, which is $0.31/kWh between noon and six from 5/1 to 10/31 in the PGE
service territory. If the customer/generator wants to gamble on the hourly PX
pricing option available to both flat rate and TOU customers, the T in TVM
could be even shorter. (Peaking energy hit $0.95/kWh for same-day hour-ahead
purchases in the San Diego area this August.) Nick says PECO in the Philly
area offers a special $0.22 kWh rate to PV net metering customers there. Other
states may have similar rate structures. In California a TOU meter costs $277,
and you may need two of them. I don't know what the special hourly meter
required for the PX rates costs.
sno
The final cost of any manufactured product can
be considered to be two things....the cost of
the energy that goes into it (including human
and/or animal) plus profit...the same goes for
any components that go into it....the components
include such things as enviromental costs..
building costs...etc....so cost is a very good
marker of energy....sno
"R.H. Allen" wrote:
>
> On Fri, 03 Nov 2000 15:22:43 GMT, see_...@dk37cv.com (Robert Scott)
> wrote:
>
> >In particular, it seems there are lots of good applications for
> >solar energy that are cost-effective or nearly so right now. Direct
> >space heating is the prime candidate. On the other hand, photovoltaic
> >is currently in such a state of development that the energy required
> >just to manufacture a bank of PV cells is greater than the total
> >energy that bank of cells can possibly produce in their lifetime
> >(they do degrade with use). No amount of shifting economic
> >paradigms can alter that fact. So currently if you use PV cells
> >you are wasting energy.
>
> No shifting economic paradigms necessary -- your fact isn't a fact.
> The energy payback period for a PV module is 8 months to 12 years,
> depending upon the type of module and the details of its deployment.
> Numerous scientific studies support this conclusion. Meanwhile, PV
> manufacturers typically offer warranties of 20 years, well beyond the
> point at which the energy investment is recovered. I suspect the
> payback time is slowly shifting even lower, since PV companies are
> beginning to use less energy-intensive raw materials.
>
> Of course, if you have any scientific studies to the contrary I'd love
> to know what they are. Nobody has been able to show me one yet, nor
> have I found any on my own (and I have looked).
Robert Scott
I agree with most of what you say. I too am a supporter of
alternative energy and have invested in some experiments along
those lines. And while I don't ask that solar energy be
economically competitive yet, and I certainly don't want to
stifle discussion, I think some discussion of cost-effectiveness
is in order.
In particular, it seems there are lots of good applications for
solar energy that are cost-effective or nearly so right now. Direct
space heating is the prime candidate. On the other hand, photovoltaic
is currently in such a state of development that the energy required
just to manufacture a bank of PV cells is greater than the total
energy that bank of cells can possibly produce in their lifetime
(they do degrade with use). No amount of shifting economic
paradigms can alter that fact. So currently if you use PV cells
you are wasting energy.
The best use of PV cells is not to save on energy costs but to
provide convenient power in remote locations where the utilities
are not available - such as on your boat or for temporary
highway signs - or remote communication stations. Too much
emphasis on PV technology as an energy saver can discredit the
whole alternative energy movement by distracting attention
from the really useful applications. If you want to generate
electricity from renewable energy, consider wind or ocean waves.
But don't pretend that PV is any kind of an energy saver.
Dlehmicke
>economically competitive yet, and I certainly don't want to
>stifle discussion, I think some discussion of cost-effectiveness
>is in order.
Sounds good, I'll start.
It's reasonable to want a PV-produced kWh to cost the same as or less then a
conventionally produced kWh if the two kWh are identical. Here are three ways
a PV-produced kWh is superior.
It is produced where it is used, reducing strain on and extending the
capability of the utility T&D system.
It is produced at the same time the utility peak demand occurs, reducing the
number of very expensive kWh the utility has to purchase from peaking power
sources.
The pollutants exhausted (or radioactive waste produced) during it's production
are at least 50% lower, and as much as 85% lower than those exhausted (or
produced) during the production of a conventional kWh.
The sources for those two numbers are:
von Meier, "Manufacturing Energy Requirements and Energy Payback of Crystalline
and Amorphous Silicon PV Modules", Proceedings of 1993 ASES Conference
(Summary: 4 month to 12 year energy payback, depending on technology)
Siemens Solar press release circa 9/00 stating their modules payback their
manufacturing energy in three years.
Which brings us to
>photovoltaic
>is currently in such a state of development that the energy required
>just to manufacture a bank of PV cells is greater than the total
>energy that bank of cells can possibly produce in their lifetime
and
>But don't pretend that PV is any kind of an energy saver.
>
Please provide references supporting the first statement. Until you do, we
will continue to pretend that you know what you're talking about.
Scott Willing
Clearly the subject of PV energy payback is open to debate, since a
number of posters have presented data that completely contradicts your
assertion that they represent a net energy cost outside of special
applications.
The ordinary citizen is left to guess what the truth might be, as
boosters and detractors grind their respective axes, present their
coloured data, and attempt to advance their own overt or covert agendas.
It would be nice to know what the truth is, but it's clear that no source
can be trusted absolutely, particularly where money is involved. And when
it comes to energy, a LOT of money is involved.
I put faith in claims in pretty much inverse proportion to how much cash
is on the line. I think this is a pretty safe policy, since especially in
North America, many people are apparently incapable of conceiving any
higher principle or metric than the almighty dollar. If that wasn't bad
enough, they tend to be pretty selective and simplistic in their choice
of factors to include in any given equation.
*On both sides of any argument.*
Cheers,
-smw
In article <3a02d82a...@news.wwnet.net>, see_...@dk37cv.com
says...
dw
sno wrote:
>
> The final cost of any manufactured product can
> be considered to be two things....the cost of
> the energy that goes into it (including human
> and/or animal) plus profit...the same goes for
> any components that go into it....the components
> include such things as enviromental costs..
> building costs...etc....so cost is a very good
> marker of energy....sno
>
> "R.H. Allen" wrote:
> >
> > On Fri, 03 Nov 2000 15:22:43 GMT, see_...@dk37cv.com (Robert Scott)
> > wrote:
> >
> > >In particular, it seems there are lots of good applications for
> > >solar energy that are cost-effective or nearly so right now. Direct
> > >space heating is the prime candidate. On the other hand, photovoltaic
> > >is currently in such a state of development that the energy required
> > >just to manufacture a bank of PV cells is greater than the total
> > >energy that bank of cells can possibly produce in their lifetime
> > >(they do degrade with use). No amount of shifting economic
> > >paradigms can alter that fact. So currently if you use PV cells
> > >you are wasting energy.
> >
Johann Beda
Tittle" <the...@tznet.com> wrote:
> I would love to cover my roof in PV panels, but the expense cannot be
> justified using the principles of Time Value of Money.
However, that is not the only way that people decide what to cover
their roof with, otherwise every roof that I see from my window would
have the same covering. Some have wood shingles, some have steel, some
have gravel, some have slate. All cost different amounts, all have
different lifetimes.
Anyone know how much PV shingles costs compared to other expensive
roof coverings? Are PV shingles even available in the US yet? I seem
to remember that they are available in Japan.
--
* johann beda *
* <mailto:j-b...@pobox.com.nospam> <http://pobox.com/~j-beda/> *
* Contact information: <XNSName: =j-beda> <http://www.xns.org/> *
dw
Kato's and they seem like they do not take into account many
factors. The others I have not seen.
dw
"R.H. Allen" wrote:
>
> On Sat, 04 Nov 2000 04:52:57 -0800, dw <wes...@pacbell.net> wrote:
>
> >And the study is located where?
>
> I quit posting that information because for awhile it seemed like I
> was posting it every week or so and just got tired of doing it. It's
> been awhile though, so here you go...
>
> K. Kato, A. Murata, and K. Sakuta, "Energy pay-back time and
> life-cycle CO2 emission of residential PV power system with silicon PV
> module," Prog. Photovolt. Res. Appl., vol. 6, pp. 105-115, 1998.
>
> K. Kato, A. Murata, and K. Sakuta, "An evaluation of the life cycle of
> photovoltaic energy system considering production energy of off-grade
> silicon," Sol. Energy Mat. Sol. Cells, vol. 47, pp. 95-100, 1997.
>
> W. Palz and H. Zibetta, "Energy pay-back time of photovoltaic
> modules," Int. J. Sol. Energy, vol. 10, pp. 221-216, 1991.
>
> H.A. Aulich, F.-W. Schulze, and B. Strake, "Energy pay-back time for
> crystalline silicon photovoltaic modules using new technologies," in
> 18th IEEE Photovolt. Spec. Conf., pp. 1213-1218, 1985.
>
> A. Inaba, K. Yamada, and H. Komiyama, "An energy evaluation for solar
> photovoltaic energy systems," in 28th Intersoc. Energy Conv. Eng.
> Conf., pp. 2.148-2.484, 1993.
>
> There are others, but I don't have them at fingertips and, therefore,
> have not included them. You can find a related paper online at
> http://www.pv.unsw.edu.au/14theuro/johnson.html; I don't recall
> whether it cites energy payback periods, though. There's also a new
> study just published by Siemens Solar -- you can find a link to it at
> www.siemenssolar.com.
>
> For what it's worth, I also have a fair number of anti-PV and
> anti-renewables papers from peer-reviewed journals, and not a single
> one of them makes the claim that PVs never pay back their energy
> investment. They never explicitly mention it, so it's not proof that
> anti-PVs concede this point, but one has to wonder why they wouldn't
> use it if PVs really don't pay back their energy investment.
Dlehmicke
sno
I agree with most of what you say, however,
believe that what you are saying is that the
cost of energy is included somewhere in the
price....
So are you arguing that the price of a panel
calculation verses cost of electricity....
is not accurate enough for you...???
All the things you bring up increase the price...so
if you figure the payback period is 10 years...then
you know that this is a outside figure...the number
of years have to be less than this....
I would also argue that you should ignore the time
value of money in the calculation...since the cost of
energy increases and decreases with inflation...and
also interest rates...and they are roughly equal...
The value of the energy you produce increases and
decreases with the cost of energy...usually going up...
That is one figure that is normally ignored by those
who are trying to figure out the payback period...
Since all estimates are based on future figures...and
no one has any way of knowing what they will be...
no method of figuring will have any real accuracy....
They are all educated guesses....
I still think using the cost of panel...and payback
period, calculated at your present cost of electricity, will
give you as accurate a figure as any other...and is a
lot easier....
Again...thank you for your thoughts....steve
"R.H. Allen" wrote:
>
> On Fri, 03 Nov 2000 20:53:43 -0500, sno <s...@groupz.net> wrote:
>
> >
> >The final cost of any manufactured product can
> >be considered to be two things....the cost of
> >the energy that goes into it (including human
> >and/or animal) plus profit...the same goes for
> >any components that go into it....the components
> >include such things as enviromental costs..
> >building costs...etc....so cost is a very good
> >marker of energy....sno
>
> I've heard that argument before and I don't buy it. I agree that it
> can be a useful tool, especially if better data isn't available, but
> by itself it ignores too many factors to be accurate.
>
> Case in point: Amorphous silicon solar panels are cheaper to produce
> than crystalline silicon panels, in part because they require less
> energy to produce. But they also have much lower efficiencies, so that
> on a cost/watt basis they are similar in price to crystalline modules.
> Thus, regardless of which technology you choose an investment of X
> dollars brings you the same amount of energy over the lifetime of the
> system. The two systems have the same cost, but require different
> amounts of energy to make.
>
> Another example: I know for a fact that Siemens gets a very favorable
> rate on electricity to its silicon production plant. I don't know for
> a fact -- but highly suspect -- that not all PV manufacturers get such
> favorable rates. Assuming this is the case, it is conceivable that two
> different manufacturers could invest the same amount of energy in
> their products but pay radically different amounts for that energy.
> The end user, in turn, might pay a different rate for energy than
> either of the manufacturers, so that users in different areas could
> have very different financial payback periods depending upon which
> manufacturer they choose and what the prevailing electrical rates are
> in their areas.
>
> Finally, your analysis ignores the effects of supply and demand. Do
> you think a home in San Francisco really required several times more
> energy to build than the same house in, say, Birmingham, Alabama? The
> PV industry is in just such a situation right now -- demand far
> outstrips supply (Astropower says it has commitments for all of its
> modules through the end of 2001, for example). There are indications
> that manufacturers are taking advantage of the situation in order to
> turn profits -- the Energy Information Administration reports that
> solar cell production costs fell by about a third in 1999, but module
> prices dropped only 8 percent.
>
> I could go on but, in a nutshell, that's why I don't buy the cost
> argument you've presented.
sno
I believe money is used as a counter for the amount
of energy...total energy....that is used in a product...
plus profit...
So I feel the monetary payback period is close to the
the energy payback period...
In fact, because of the profit that is involved, it will
be a higher value....so once you figure the money payback
period you know the energy payback with be a little less
time....
It is the easiest calculation and probably the closest to
reality...because if you try to figure the energy costs
individually, for each estimate you make, of energy used
to produce, you will have an error...and the errors will
be accumulative.....thus leading to a very inaccurate
calculation....and one that can be biased, unintentionally,
in one direction or the other....
I believe at the present time the energy generated by a panel
will more then pay for itself...however, if you used average
system costs...panel plus storage plus inverter.....the costs
exceed that which can be recooped.....and thereby the energy
necesarry to produce these components....steve
>
> Energy payback period is the time required for the module to generate
> the same amount of energy that was required to produce it. It's purely
> a comparison of watt-hours in versus watt-hours out -- money doesn't
> even enter the picture. This is what I am talking about.
>
> Are we on the same page?
Anthony Matonak
>
> I think our disagreement is in what money measures....
> I believe money is used as a counter for the amount
> of energy...total energy....that is used in a product...
> plus profit...
>
> So I feel the monetary payback period is close to the
> the energy payback period...
Well, it's the 'plus profit' which is what throws the wrench into the
works here.
I myself (no expert by any means) will agree that typically all the
costs, labor, energy, facilities, bribes, etc. will be included in
the final price of an object which will typically be higher to include
profits. Except in unusual circumstances, like dumping, loss leaders,
bait and switch, the price of an object is always higher than it's cost.
The question is, how much of that price is cost and then how much of
that cost is energy? Take something like diamonds, estimates vary, but
I've heard profit margins that are downright astounding. I know for a
fact that most breakfast cereals sell for a great many times what they
cost. The retail price then becomes the very TOP end of what the costs
can be. The profit margin on that panel might be anywhere from a couple
percent to a couple thousand percent.
For instance, I did a little research on small 9 volt solar panels a
month or so back and found one china firm would ship them to you in
bulk for some $4.25 each (prices from memory) and various other places
would sell you this same panel retail for anywhere from $11 to $32.
Profit on this panel in the United States was anywhere from $6.75 to
$27.75.
Then you can factor in how much profit that Chinese company was making.
Then you can factor in how much profit the various makers of raw
materials sold to that Chinese company were making.
The actual energy costs for that particular panel might well have been
much less than $1 yet it could be sold for over $32. Without knowing all
the profit margins and markups along the chain it would be impossible to
even guess how much of that retail price was energy and how much was
everything else.
Then you can complicate it even more by trying to compare this unknown
cost of production (based on it's retail price) against the comparative
value of the energy that panel could produce in it's estimated lifespan.
Compared to what? Against grid power at 7 cents a kwh? Against generator
power at 50 cents a kwh? Against running a grid line twenty miles out to
the homestead? Your payback time could vary between instant to hundreds
of years simply by comparing against different electric sources.
Nah, it may appear simple to look at it strictly from a dollars standpoint
but it's really much, much more complicated than just trying to figure out
how much energy goes into making it. This is especially difficult because
many companies do not like revealing profit margins.
Anthony
Dlehmicke
>of energy...total energy....that is used in a product...
>plus profit...
How do you account for the cost of raw material, labor, facilities other than
energy (including land), and equipment?
Why did the first hand held calculators cost $100 when today the same functions
cost $10? The energy required to build the calculator did not drop by 90%.
Why do PCs cost $500 today when less powerful ones cost $3500 five years ago?
Did the required energy drop 86%?
A mature product which is no longer paying for research, design, engineering,
marketing, building mortgage and other overhead still has to pay for raw
materials, labor, energy, equipment upgrades, and profit. The question is what
fraction of that total goes to pay for energy. I'm led to believe for aluminum
foil, energy may be a large part of the total cost. As the product gets more
complex, with more assembly steps and handling, the labor portion increases.
As assembly and handling becomes automated, the labor portion decreases. Some
PV modules assembly steps are becoming highly automated.
Another problem with linking economic payback and energy payback: In the PG&E
territory, a time-of-use PV customer/generator with no home load between noon
and six will sell PV kWh to the utility for $0.31 each between May and
November. A flat rate customer will sell the same number of PV kWh for $0.12
each during the same period. The economic payback will be 1.5 times longer in
the second case, but the energy paybacks will be identical.
sno
Ok....if you want to get closer to the exact energy
used....take the components of the system...in the
case of panels would probably be glass..aluminum and
purified silicon....since the companies that produce
these items are public companies, you can get their
yearly reports....and from them can calculate the
actual profits, by subtracting such things as taxes...
Whoops...that won't work..you would need to know what
percentage of an item went into the final product....
I wonder if there isn't somewhere out there a percentage
figure that applies roughly to all products...that shows
what percentage is profit....it seems that would be
something that economists would use..and would have
calculated....
Anyway...in real life we are talking a system...am sure
that the energy costs of the whole system are greater
then is produced over the lifetime of a panel...so at
this point there is no real reason to determine if
the energy that goes into a panel is recooped....at
the point that the monetary costs of system, are
equal to the cost of the energy the panel will produce,
over its lifetime, we can say for sure that the systems
energy exceeds the energy used to produce....steve
Dlehmicke
>that the energy costs of the whole system are greater
>then is produced over the lifetime of a panel...
We want to be sure, too. Please tell us what makes you sure, so we can be
sure.
>at
>the point that the monetary costs of system, are
>equal to the cost of the energy the panel will produce,
>over its lifetime, we can say for sure that the systems
>energy exceeds the energy used to produce....
If, but not if and only if.
Nick Pine
>I believe money is used as a counter for the amount of energy...
>total energy....that is used in a product... plus profit...
We can use a crop of out-of-season lettuce as an example. If lettuce is
planted in a 30 by 100 foot greenhouse at a spacing of 10 by 10 inches,
that amounts to 4200 lettuces. It requires a sheet of polyethylene
plastic 42 by 100 feet to cover that greenhouse. Therefore, we can
assign one square foot of plastic to each lettuce.
All the energy used in raw materials, production, and delivery of a
manufactured item is defined by the term "embodied energy." The embodied
energy in one square foot of 6 mil polyethlyene greenhouse plastic...
is 1221 Btu.
If, on the other hand, the lettuce were grown in California, it would
have to be transported 3200 miles from California to the east coast.
We need to know the energy consumption of a semi-tractor-trailer driven
across the country and divide by the number of lettuces per load. I found
three different figures from three different transportation energy data
sources. Based on the average from those figures the energy consumption
per 12 oz. head of lettuce to transport a semi-tractor-trailer load
3200 miles from California to the East Coast is 3034 Btu.
According to those calculations, the lettuce grown in my Maine greenhouse
requires only 40% as much energy. However, since the greenhouse
polyethylene lasts three years and since a grower can get both a spring
and a fall crop each year with no other energy input, six lettuces can
be produced over the lifespan of that square foot of polyethlyene. Each
local greenhouse grown lettuce thus consumes only 6% of the energy
required by each trucked-in lettuce.
For the sake of simplicity, only the energy in the plastic cover and
the energy used in transportation have been considered. They are the
key factors in each system. I have not included the greenhouse pipe
frame, nor the truck and its refrigeration unit, nor the highway
construction. I am sure that analysis of these energy figures would
make the ratio even more favorable to the Maine grown lettuce. Nor
have I considered any pollution from the plastic manufacturing and
recycling process compared to the pollution from the burning of the
average 582 gallons of diesel fuel used in cross-country trucking.
These are obviously problems that need to be solved but they are
outside this grown-in-Maine vs grown-in-California comparison.
At the moment polyethylene covered greenhouses are the economic
choice for me as a grower. I would love to avoid "plastic" but a
comparable glass covered greenhouse would cost more than ten times
as much as a plastic house. Glass also contains ten times the
embodied energy of plastic--12,000 Btu per square foot. Having said
that, do I believe greenhouses covered with plastic made from
non-renewable petroleum feedstocks make any more long-term sense
than transportation based on those same non-renewable feedstocks?
Obviously not. We need to address the use of non-renewable resources
as a factor in any out-of-season produce discussion.
Since greenhouse plastic is made from petroleum feedstocks, the
question is whether this useful material can be made from some
renewable raw material when our economy's present fixation with
petroleum comes to an end. I am assured by friends who understand
polymer chemistry that greenhouse plastic can indeed be made from
renewable materials and that many plant-based compounds would be
suitable feedstocks. Maybe that is an option that could be demanded
by growers. However, I suspect it is an option that will likely
happen on its own someday when dictated by the comparative cost of
feedstocks.
from The Winter Harvest Manual by Eliot Coleman, 1998
sno
content of an item was such a small part....
Thank you for the nice conversation....and the
learning.....steve.....
Brett Aubrey
http://www.siemenssolar.com/090600.html
The headline is: NEW STUDY SHOW SIEMENS SOLAR PANELS
ENERGY PAYBACK TIME IS ONE TO THREE YEARS.
Camarillo, Calif., September 6th, 2000.
and states: It is an empirical study that is complementary with
other research that employs production modeling.
Regards, Brett.
dw wrote:
> Thanks. I will end up busy for a week now. I have seen ...
Brett Aubrey
W Bradford Tittle
My current Electric needs are about $400/ year. So how many years for me to
pay for my new PV panels.
TNT
Brad
----------
In article <3A0B9577...@Home.com>, Brett Aubrey
Sylvan Butler
>I still say how much is going to cost to hook up my house.
That's a good question, but probably irrelevent to 2/3 of the newsgroups
posted to.
>My current Electric needs are about $400/ year. So how many years for me to
>pay for my new PV panels.
Well, that depends. How much electricity do you use (capacity)? How
fast do you use it (peak and spread demand)?
The amount you pay is quite irrelevent without more information. For
example, you may be in the pacific northwest USA and pay 5c/kwh, or you
may be on a little island off the coast and pay 40c/kwh. You may use a
trickle of electricity all the time, or pay demand rates with one large
demand and very little actual usage (e.g. my former high school paid
over one thousand dollars in demand charges if they simple turned on
(even if immediately turned off) the lighting on the football field).
Solar PV panels start around $4/watt in generating capacity. You may
get that capacity for an average of 6 hours per day (effectively
$16/daily-watt-hour), or maybe only 4 ($24/daily-watt-hour). You will
probably want to store some electricity for overnight and cloudy days.
Your peak demand may be low and cheap, or it may be high and expensive.
The more generating capacity, the more storage, or the higher the peak
demand the more expensive will be your system.
But anyone who expects someone currently on the grid to find solar PV
competitive on a dollar/kwh basis alone, is in a dream world.
sdb
--
More guns means less crime. ISBN:0-226-49363-6
***
Watch out for munged e-mail address.
User should be sylvandb and host is at bigfoot.com
Do NOT send me unsolicited commercial e-mail (UCE)!
Dlehmicke
>competitive on a dollar/kwh basis alone, is in a dream world.
>
On 1/1/01, California AB 918 takes effect. Then PV net metering
customer/generators can get time-of-use rates for their back-fed kWh ($0.31/kWh
from noon to six, May through October in PG&E's territory.) Near San Jose,
generation for a fixed-tilt array averages out to something like
$0.32/installed kW each year (using 2000 hours, 85% system efficiency from
nameplate, a 45/30/15/10 breakdown for summer on/winter on/summer off/winter
off percentages, and 31, 11.5, 8.8, and 8.5 cents/kWh, respectively, resulting
in an average $0.1872/kWh ).
Gamblers can try PX rates, tied to the California Power Exchange hourly prices.
I don't have historical data for those (it's on PGE's web site somewhere), but
this August same-day, hour-ahead peak purchases were going for $0.95/kWh in
Southern California. PX rates are undoubtedly averaged and not that high.
Anyone trying these rates better keep tight control on their on-peak
consumption. TOU meters cost $277, and you may need two. I don't know the cost
of hourly recording meters.
Nick says PECO in Philly has a $0.22/kWh rate for their PV customer/generators.
Don't know if that's time-of-day and/or time-of-year dependent.
Brett Aubrey
> More guns means less crime. ISBN:0-226-49363-6
This is simply NOT true - in culturally similar U.S. and Canada,
the death rate by guns *more than three times higher* in the U.S.
than it is in Canada, on a per capita basis. The general crime
rate is also much higher, 'though I don't have the numbers at
this time. Regards, Brett.
Sylvan Butler
mail a copy of a post, and not mention that it is a copy?
On Fri, 17 Nov 2000 18:35:39 GMT, Brett Aubrey <Brett....@Home.com> wrote:
>Sylvan Butler wrote:
>> More guns means less crime. ISBN:0-226-49363-6
>
>This is simply NOT true - in culturally similar U.S. and Canada,
It is true. Read the book. For anyone who is interested, the rest of
this conversation has occurred via e-mail. Just send me a mail and I'll
send you a copy.
sdb
--
More guns means less crime. ISBN:0-226-49363-6
***
Watch out for munged e-mail address.
User should be sylvandb1 and host is at bigfoot.com
Brett Aubrey
your copy of the Header - it's in my "Sent" copy), and I noticed on
your first reply that YOU had omitted the NewsGroup. I just politely
followed your lead, assuming you wanted to keep it private for some
reason. There WAS NO COPY and I resent your implication. A "Reply
All" is also what I'm doing now. I do note, however, note that the
NewsGroup does not contain the "To:" line. Regards, Brett.
Sylvan Butler
would be appropriate.
>Sylvan Butler wrote:
>> Great, now it shows up in news also. Don't you know it is very
>> rude to mail a copy of a post, and not mention that it is a copy?
Evidently he didn't know. Now he does. The follow was sent in response to
the e-mailed copy of this latest post:
------------------------
On 21 Nov 2000, at 10:48, Brett Aubrey wrote:
> Hey! All I did was a "Reply All" (the NewsGroup should have been in
> your copy of the Header - it's in my "Sent" copy), and I noticed on
Headers are insufficient notice of dual messages. A newsgroup header has
no meaning in an e-mailed message. It certainly does NOT mean the message
was mailed and posted.
It is proper to put a notice at the top of at least the mailed copy, to
the effect "this message has also been posted." A conformant news client
will do this automatically.
Of course, now we know your news client is not conformant to the
guidelines, because it also ignores the "mail-copies-to" header,
which specifies I never want to receive copies by e-mail. (And for
that, the header is standard.)
> reason. There WAS NO COPY and I resent your implication. A "Reply
What implication? I certainly never meant to imply anything I did
not state. I apologize if I was unclear.
There most definitely was a copy. Evidently you allowed your news
client to send a copy of the article to the group, and also send a
copy via e-mail. If it did not tell you it was doing that, it was in
violation of the GNKSA guidelines. If you knew it was doing that, you
cannot blame the breach on ignorance. Now you know.
If you have any further questions concerning this topic, please ask
in news:news.software.readers where someone, maybe me, is sure to go into
excruciating detail re. the two copies.
> All" is also what I'm doing now. I do note, however, note that the
OK, I'll go post this in news also when your response gets to my news
server.
sdb
------------------------
Brett Aubrey
> >Sylvan Butler wrote:
> >> Great, now it shows up in news also. Don't you know it is very
> >> rude to mail a copy of a post, and not mention that it is a copy?
> Evidently he didn't know. Now he does. The follow was sent in response to
> the e-mailed copy of this latest post:
> ------------------------
> On 21 Nov 2000, at 10:48, Brett Aubrey wrote:
> > Hey! All I did was a "Reply All" (the NewsGroup should have been in
> > your copy of the Header - it's in my "Sent" copy), and I noticed on
>
> What implication? I certainly never meant to imply anything I did
> not state. I apologize if I was unclear.
Well this is all news to me...
The implication that what I did was "very rude". If my "non-conforant"
news client did something that it's done many, many times before without
anyone complaining, then it's not me being rude.
> There most definitely was a copy. Evidently you allowed your news
> client to send a copy of the article to the group, and also send a
> copy via e-mail. If it did not tell you it was doing that, it was in
> violation of the GNKSA guidelines. If you knew it was doing that, you
> cannot blame the breach on ignorance. Now you know.
No, I didn't know. Yes, I do now. I trust you're aware that few people
(at least of those I've dealt with) know anything about this. Does any-
one try to get these guidelines out to the general usercommunity? And
is there any authority, or are these just guidelines (i.e. what are the
consequences for non-conformant news clients or breaches of guidelines?)
> If you have any further questions concerning this topic, please ask
> in news:news.software.readers where someone, maybe me, is sure to go into
> excruciating detail re. the two copies.
I'm sure I will have.