WHAT PERCENTAGE
sam...@hetnet.nl
to be covered with PVs to supply all of today's power needs assuming
10 % efficiency of the PV panels ?
Joe Fischer
Probably about 5 percent, but a the majority of "power"
is used as thermal energy, which can be more than 50 percent
efficient.
Chances are that solar PV or nuclear will be needed
within a hundred years or so, maybe sooner if the Arabian
producers decide to limit oil production to make it last longer,
simply because a lot of auto use will have to switch to electric.
Even 3 or 4 square meters of panels on top of an electric
vehicle would be very useful, and would work well with hybrid
systems, which the auto industry is dragging their feet on.
But higher voltage systems are needed, and a good
design battery box is needed with a cover that disconnects
all batteries when the cover is removed (to prevent shock
hazards). Government regulations won't help though,
good design will make the difference.
A hybrid will get 2 to 4 times the mileage as present
cars. Solar thermal must accompany PV to achieve the
reduction in fossil fuels.
There just isn't enough fuel to sustain the world
as it is now, unless everybody moves to the tropics.
Joe Fischer
Henry
"sam...@hetnet.nl" <sam...@hetnet.nl> wrote:
Assuming 6E6 people.
Assuming energy consumption of 11.5 kW (USA1999).
Assuming 1 kW per square metre insolation.
Assuming 10% efficiency panels.
6E6 * 11.5 kW = 69E6 kW required to sustain population
=> 69E6 square metres at 100% efficiency
=> 690E6 square metres at 10% efficiency
690E6 square metres = 690 square kilometres
...a circular array less than 27 km in radius.
...a negligible percentage of the Earth's surface.
Henry.
Ron Rosenfeld
Although your conclusion that the array represents a small proportion of
the earth's surface, your figures are considerably off.
First of all, as of this morning, the world's population is thought to be
6.37E9, or several orders of magnitude greater than your estimate.
Also, the 1kWh/M2 insolation is per hour. So for the purpose of this
exercise, I would figure that the panels would be sited where insolation is
at least 4 and possibly 6 hours per day. One would have to do a tradeoff
between generating efficiency and transmission loss problems to find the
best sites. For the sake of argument, let's use 4 hrs.
Since solar panels are now better than 10% efficiency, I would not make any
change in this factor and allow the increased efficiency to account for
transmission losses.
In any event, with those factors plugged in, I get a circular array with a
radius of about 242 km, or a square that is 266 miles per side.
The approximate land surface of the earth comprise 150,000,000 sq km; so
the solar panels would occupy about 0.12% of the earth's land area.
Still, a negligible percentage.
-- ron (off the grid in Downeast Maine)
Simon
news:urael-56B7DA....@lon-reader.news.telstra.net...
> In article <gu30pvc8nqmnqljnl...@4ax.com>,
> "sam...@hetnet.nl" <sam...@hetnet.nl> wrote:
>
> > What percentage of the Earths surface (excluding oceans) would need
> > to be covered with PVs to supply all of today's power needs assuming
> > 10 % efficiency of the PV panels ?
>
> Assuming 6E6 people.
6 million? A large city has more than that. 6E9 is more like it.
> Assuming energy consumption of 11.5 kW (USA1999).
Americans consume about 2-3 times the amount of some developed countries,
and many Africans would barely compare. Also 11.5kW is a measure of power,
not energy consumption, although 11.5kW run 24/7 sounds right (for the USA).
> Assuming 1 kW per square metre insolation.
Only if normal to the sun, without cloud cover.
> Assuming 10% efficiency panels.
>
> 6E6 * 11.5 kW = 69E6 kW required to sustain population
Americans in the future will be forced to use less power so that rate will
have to be less for them. It is also too naive to use one value for all. I
don't suppose someone in the tropics will have my heating bill for example.
Oh and the population is continuing its relentless increase...
> => 69E6 square metres at 100% efficiency
> => 690E6 square metres at 10% efficiency
>
> 690E6 square metres = 690 square kilometres
> ...a circular array less than 27 km in radius.
> ...a negligible percentage of the Earth's surface.
>
> Henry.
The values you calculated is the area that is normal to the sun without
being blocked, for an incorrect population.
Of course this area needs to be adapted because the world rotates, so panels
will have a variation in the power produced during any given day, and extra
need to be used to allow for overcast days. Also the location of the panels
is significant. The Sahara is a higher energy density area for sunlight than
here in blighty. Oh and don't forget the seasonal variation, and the daily
peaks in demand.
A prediction from a slightly out of date text book puts energy consumption
at 6E20J per annum (including losses, ie it's a measure of oils' calorific
value and not the energy extracted). Assuming we get 1/4 out the demand
becomes 1.5E20Jpa.
As Joe says, much of the demand is for space heating which is much more
efficient than 10%.
This equates to 4.76E12 Watts. Since much is used for heating divide by
perhaps 2, so 2.38E12 is needed as photovoltaics. Thats...
2.38E10 metres squared,
or a square with sides of around 155km, but again, that's the unshaded
normalized value. You'll need far more to generate that energy and cover for
peak demands.
Really there is no single answer to the question, only approximations with
guess work.
<little rant>
Energy demands really have to fall in the future, and they will. Air travel
will die. The days of 5.0L 2 tonne SUV's are numbered. Commuting will become
more expensive, so people will less able/less willing to commute stupid
distances on a daily basis, electrical appliances will become more efficient
and homes will be better insulated. Much can be done with regulation, but
the real changes will be due to consumer awareness and those prohibitive
energy costs. Products will also become more expensive again, so the waste
of the throw away age will dissappear, which will also reduce our energy
consumption. That's assuming global warming doesn't cause thermal runaway
first. God help us!
</little rant>
Simon.
Simon
news:21d0pv4sjbufpg7gn...@4ax.com...
> On Fri, 17 Oct 2003 "sam...@hetnet.nl" <sam...@hetnet.nl> wrote:
>
> >What percentage of the Earths surface (excluding oceans) would need
> >to be covered with PVs to supply all of today's power needs assuming
> >10 % efficiency of the PV panels ?
> Chances are that solar PV or nuclear will be needed
> within a hundred years or so, maybe sooner if the Arabian
> producers decide to limit oil production to make it last longer,
> simply because a lot of auto use will have to switch to electric.
100 years is very optimistic with the current level of population. If the
Arabian producers limited production that would be a good thing. Imagine
running the wells dry and oil production stopped suddenly. Who would be
prepared? Who could cope with such a sudden loss in energy. It's a recipe
for disaster.
People seem to want to find new ways of generating more power to feed their
current excessive demand. It's actually much better to use the energy more
wisely.
> Even 3 or 4 square meters of panels on top of an electric
> vehicle would be very useful, and would work well with hybrid
> systems, which the auto industry is dragging their feet on.
Useful but the economics don't make any sense yet. Far better to have
smaller lighter and more aerodynamic cars.
> Government regulations won't help though,
> good design will make the difference.
The real kick will be costs. If Americans had our fuel bills, their cars
would look a lot different. ~78 pence per litre. ($1.20?)
> A hybrid will get 2 to 4 times the mileage as present
> cars. Solar thermal must accompany PV to achieve the
> reduction in fossil fuels.
Agreed. Along with wind, biomass, geothermal, and lower populations. If only
the pope would re-think his attitude to birth control :-) It's not just
energy we're consuming, its the whole earth.
> There just isn't enough fuel to sustain the world
> as it is now, unless everybody moves to the tropics.
Which are rapidly disappearing :-(
Simon.
PS I'm not as miserable as I may sound :-)
Henry
Assuming 6E9 people.
Assuming energy consumption of 11.5 kW (USA1999).
Assuming 1 kW per square metre insolation.
Assuming 10% efficiency panels.
6E9 * 11.5 kW = 69E9 kW required to sustain population
=> 69E9 square metres at 100% efficiency
=> 690E9 square metres at 10% efficiency
690E9 square metres = 690,000 square kilometres
...a circular array around 265 km in radius.
Henry
"Simon" <le...@exit.com> wrote:
> > Assuming 6E6 people.
>
> 6 million? A large city has more than that. 6E9 is more like it.
Doh! Mea culpa.
> > Assuming energy consumption of 11.5 kW (USA1999).
>
> Americans consume about 2-3 times the amount of some developed countries,
> and many Africans would barely compare. Also 11.5kW is a measure of power,
> not energy consumption, although 11.5kW run 24/7 sounds right (for the USA).
11.5 kW == 11,500 Joules per Second. Looks like energy consumption to
me! :) That figure came from the US DoE.
> > Assuming 1 kW per square metre insolation.
>
> Only if normal to the sun, without cloud cover.
The vast majority of the panels would be located in areas which have
negligible problems with cloud cover. Since it is expected to power the
entire population of the planet, and the planet spins, such an array
would--by necessity--be distributed across various time zones.
Normality to the sun is thus not as much of an issue as one might think.
> > Assuming 10% efficiency panels.
> >
> > 6E6 * 11.5 kW = 69E6 kW required to sustain population
>
> Americans in the future will be forced to use less power so that rate will
> have to be less for them. It is also too naive to use one value for all. I
> don't suppose someone in the tropics will have my heating bill for example.
They wouldn't need heating--they would need cooling instead. Six of
one, half-a-dozen of the other.
> The values you calculated is the area that is normal to the sun without
> being blocked, for an incorrect population.
The original message has been superseded with a corrected one.
> As Joe says, much of the demand is for space heating which is much more
> efficient than 10%.
Granted, but the OP just wanted a figure for 10% efficient PV.
> This equates to 4.76E12 Watts. Since much is used for heating divide by
> perhaps 2, so 2.38E12 is needed as photovoltaics. Thats...
> 2.38E10 metres squared,
> or a square with sides of around 155km,
My population-corrected value was a circle with radius 265 km. We're in
the same ballpark.
> Really there is no single answer to the question, only approximations with
> guess work.
Yup, but that's all the OP wanted. He's not thinking of building one,
just wants a rough idea. Since the original post framed the question in
terms of a percentage of the Earth's surface, he--like many
people--probably (incorrectly) thought that a non-trivial percentage of
the Earth's surface would be required.
> <little rant>
> Energy demands really have to fall in the future, and they will. Air travel
> will die.
That's a bold prediction. Why do you think that will happen?
> The days of 5.0L 2 tonne SUV's are numbered.
Is the trend in the USA still upward, or is it starting to level off?
> Commuting will become
> more expensive, so people will less able/less willing to commute stupid
> distances on a daily basis,
And communication technologies will eliminate the need for many to do so.
> electrical appliances will become more efficient
> and homes will be better insulated.
Well-insulated homes are vitally important. I think something like 40%
of the average (Oz) household's energy gets used in heating/cooling the
home.
> Much can be done with regulation, but
> the real changes will be due to consumer awareness and those prohibitive
> energy costs.
Do you think spiralling energy costs will lead to consumer awareness
which will lead to an increase in demand for efficient
items/technologies, or do you predict some other scenario?
Henry.
Henry
Ron Rosenfeld <ronros...@nospam.org> wrote:
> Although your conclusion that the array represents a small proportion of
> the earth's surface, your figures are considerably off.
>
> First of all, as of this morning, the world's population is thought to be
> 6.37E9, or several orders of magnitude greater than your estimate.
Yep. Typo. The article has been corrected.
> Also, the 1kWh/M2 insolation is per hour.
Yeah, I guess you could write it that way. It's just simpler to write 1
kW per square metre.
> So for the purpose of this
> exercise, I would figure that the panels would be sited where insolation is
> at least 4 and possibly 6 hours per day. One would have to do a tradeoff
> between generating efficiency and transmission loss problems to find the
> best sites. For the sake of argument, let's use 4 hrs.
>
> Since solar panels are now better than 10% efficiency, I would not make any
> change in this factor and allow the increased efficiency to account for
> transmission losses.
>
> In any event, with those factors plugged in, I get a circular array with a
> radius of about 242 km, or a square that is 266 miles per side.
I got a circle with radius of 265 km. Same ballpark.
> The approximate land surface of the earth comprise 150,000,000 sq km; so
> the solar panels would occupy about 0.12% of the earth's land area.
>
> Still, a negligible percentage.
Yup. Nearly every continent has a spare desert that could be used.
Henry.
James Logajan
Assuming only ~3 full-sun-hours/day insolation and ~10% conversion (the
theoretical thermodynamic limit is ~95% conversion efficiency (though not
with PV cells)) you'd need an area of land (or sea) of ~1,000,000 km^2 (a
square of ~1,000 km * 1,000 km) to replace ALL other sources of power for
the ENTIRE world, which is estimated to be on the order of ~400 quadrillion
BTUs/year (~4*10^20 J/year):
http://energy.cr.usgs.gov/energy/stats_ctry/Stat1.html .
By comparison, the total surface area taken up by water reservoirs is
about 500,000 km^2:
http://webworld.unesco.org/water/ihp/publications/waterway/webpc/pag21.html
I don't know what the surface area of farmland is, but I'm sure if only a
small fraction of it were turned over to direct solar power production
(as opposed to the low efficiency production of food energy) it would also
suffice.
The total land surface area of the Earth is ~150,000,000 km^2 (from
http://hypertextbook.com/facts/2001/DanielChen.shtml ) so the percentage
needed is (drum roll, please...) 100*1,000,000/150,000,000 ~=
0.67%
Less than 1% of the land surface - about twice what is consumed by water
reservoirs and probably vastly less than used for farming.
(Modified from a post I made elsewhere that assumed 20% efficiency:
http://groups.google.com/groups?selm=Xns93FC9001452C4JamesLLugojcom%40129.250.170.85 )
daestrom
"Henry" <ur...@zrgebcbyvf.arg.nh> wrote in message
I would disagree a bit here. If the power required is 69e9 kW, then you
must produce that continuously, 24/7. To get this, a simple way would be to
have 24 of these 690 000 square kilometre arrays spread evenly around the
globe. Of course that isn't practical, and an array would produce for more
than just one hour out of every day (on average). So if we assume each
array is capable of generating its rated power output for, oh, say 4 hours a
day on average, then you would still need at least six of these arrays
spread out around the globe.
Still a negligible percentage, but perhaps a bit more accurate to consider
this 'duty cycle'.
daestrom
Simon
> In article <bmrf4v$ess$1...@hercules.btinternet.com>,
> "Simon" <le...@exit.com> wrote:
>
> > > Assuming 6E6 people.
> >
> > 6 million? A large city has more than that. 6E9 is more like it.
>
> Doh! Mea culpa.
> 11.5 kW == 11,500 Joules per Second. Looks like energy consumption to
> me! :) That figure came from the US DoE.
Looks like a rate of consumption to me, but I'm splitting hairs.
> > > Assuming 1 kW per square metre insolation.
> >
> > Only if normal to the sun, without cloud cover.
>
> The vast majority of the panels would be located in areas which have
> negligible problems with cloud cover. Since it is expected to power the
> entire population of the planet, and the planet spins, such an array
> would--by necessity--be distributed across various time zones.
> Normality to the sun is thus not as much of an issue as one might think.
Yes but that power is only at mid-day. You did not allow for the panels to
only produce in daylight hours. Your calculations would only give a
normalized equivalent value that the real area would need to match.
> > > Assuming 10% efficiency panels.
> > >
> > > 6E6 * 11.5 kW = 69E6 kW required to sustain population
> >
> > Americans in the future will be forced to use less power so that rate
will
> > have to be less for them. It is also too naive to use one value for all.
I
> > don't suppose someone in the tropics will have my heating bill for
example.
>
> They wouldn't need heating--they would need cooling instead. Six of
> one, half-a-dozen of the other.
Take a siesta like the spanish :-)
> > As Joe says, much of the demand is for space heating which is much more
> > efficient than 10%.
>
> Granted, but the OP just wanted a figure for 10% efficient PV.
As Joe also pointed out, much of that demand is for space heating, and solar
colectors would be better, but you are correct, that was not the question.
> > This equates to 4.76E12 Watts. Since much is used for heating divide by
> > perhaps 2, so 2.38E12 is needed as photovoltaics. Thats...
> > 2.38E10 metres squared,
> > or a square with sides of around 155km,
>
> My population-corrected value was a circle with radius 265 km. We're in
> the same ballpark.
>
> > Really there is no single answer to the question, only approximations
with
> > guess work.
>
> Yup, but that's all the OP wanted. He's not thinking of building one,
> just wants a rough idea.
My main point here is that 1km^2 in the Sahara is worth much more than 1km^2
in northern Europe for example. So the question of how much area needs also
to be answered with where that area is.
> > <little rant>
> > Energy demands really have to fall in the future, and they will. Air
travel
> > will die.
>
> That's a bold prediction. Why do you think that will happen?
What will you run the jets on? It'll not die completely, and it will be for
a while yet, but how will you fuel them? Other fuels exist, but not in the
quantities needed. Air travel will become ever more expensive.
>> The days of 5.0L 2 tonne SUV's are numbered.
>Is the trend in the USA still upward, or is it starting to level off?
Don't know, but I doubt it (I'm not American BTW).
> > Commuting will become
> > more expensive, so people will less able/less willing to commute stupid
> > distances on a daily basis,
>
> And communication technologies will eliminate the need for many to do so.
Will that be before or after we get the paperless office? <LOL>
> > electrical appliances will become more efficient
> > and homes will be better insulated.
>
> Well-insulated homes are vitally important. I think something like 40%
> of the average (Oz) household's energy gets used in heating/cooling the
> home.
I'm sure much of our heating costs is due to our need for fresh air. We have
to rely on drafts or open windows. We would benefit from a heat exchanger,
but it's a rented house, so I'm not about to fit one. Perhaps I should
pester the landlord or try for a government grant?
> > Much can be done with regulation, but
> > the real changes will be due to consumer awareness and those prohibitive
> > energy costs.
>
> Do you think spiralling energy costs will lead to consumer awareness
> which will lead to an increase in demand for efficient
> items/technologies, or do you predict some other scenario?
Most things boil down to money. Solar panels repay their 'carbon cost' in a
couple of years or so, but may take 30 years to recover their financial
cost. (Will depend on locale of course.) While this is the case, they will
not be common, (although the market is rising by 30% per annum). At 8 pence
per KWh, PV's simply make no real sense here in the UK. (1KW peak ~> 750KWh
per annum).
With regards to how I personally see the future, don't get me started, I'll
go on for hours, and it would definately be off topic, but if fuel gets
expensive we'll all be more frugal with it. Products will all become more
expensive, more expensive to make and ship. We'll also be more inclined to
look after goods and repair them when they break rather than simply throw
out and replace. Products that are more efficient will naturally be more
desireable. All of these changes in attitude will be driven by cost, and not
because society develops a conscience.
To reduce consumption now rather than later, (and soften the impact of
deminishing fossil fuels,) you need to push up the price of fuel
artificially. Nobody likes to pay more, so it would be unpopular. In the UK
fuel is one of the most expensive in Europe. We hate that. As a result our
average car size is relatively small. Gas prices in the states is very low,
and their average car size is much bigger. The US is the worst offender in
energy consumption by a mile. No surprise really. Something else that is
abundant in the states is food, and so Americans are also the fattest race
in the world, which also explains the car size. If anything is abundant you'
ll consume it without thinking. If it's scarce you'll be far more careful.
I think I'll stop there.
Simon.
PS if anyone reading is American, I'm not trolling for a flame war!
Joe Fischer
>My main point here is that 1km^2 in the Sahara is worth much more than 1km^2
>in northern Europe for example. So the question of how much area needs also
>to be answered with where that area is.
Land in the Sahara is probably not worth more ( :-) ), but
it would definitely produce more PV electricity.
And there is plenty of it, probably obtainable at a very
low cost per square km.
In fact, it is hard to understand why plans are not being
made to build large PV farms in theSahara, with collectors a few
feet in the air it would produce shade and some of the power
produced could be used to desalinate sea water, and irrigate
(not spray) the areas under the collectors and grow food.
I don't know why gas prices are bouncing around
so much, it was $1.39 when I bought gas 3 days ago,
and now it is $1.59 for regular unleaded.
Higher oil prices would force more alternate energy
and PV installations to happen fast.
I saw an ad on TV for coal produced electricity,
and I don't understand that, grid users probably have
no idea what produced their electricity.
The US has enough coal and shale oil to last
hundreds of years, all it will take to start using it
is higher oil prices.
So maybe the real question is, "At what cost
per kilowatt does PV have to reach to be competitive
with oil from coal or shale?".
I am getting impatient waiting for a hybrid car
with some PV on the top. If a motor manufacturer
is not going to produce a low cost 20 horse DC motor,
then there should be a grass roots effort to take
front wheel drive cars and put two 220 volt 20 HP
3 phase motors in the front, one to each front wheel.
I would also like to see a car like that with
a third motor driving the rear wheels.
I think a solid state vibrator can easily be built
to convert 220 DC to 220 AC three phase.
A sucessful car like this would go a long way
in making PV more useful in reducing oil usage.
Joe Fischer
Steve Spence
<snip>
> I don't know why gas prices are bouncing around
> so much, it was $1.39 when I bought gas 3 days ago,
> and now it is $1.59 for regular unleaded.
> Higher oil prices would force more alternate energy
> and PV installations to happen fast.
We were paying $1.70 for reg. unleaded a week ago, now it's $1.59
>
> I saw an ad on TV for coal produced electricity,
> and I don't understand that, grid users probably have
> no idea what produced their electricity.
> The US has enough coal and shale oil to last
> hundreds of years, all it will take to start using it
> is higher oil prices.
>
> So maybe the real question is, "At what cost
> per kilowatt does PV have to reach to be competitive
> with oil from coal or shale?".
>
> I am getting impatient waiting for a hybrid car
> with some PV on the top. If a motor manufacturer
> is not going to produce a low cost 20 horse DC motor,
> then there should be a grass roots effort to take
> front wheel drive cars and put two 220 volt 20 HP
> 3 phase motors in the front, one to each front wheel.
> I would also like to see a car like that with
> a third motor driving the rear wheels.
There is not enough real estate on top of a car to make pv more than a
trickle charger.
What will 20hp do for you?
Where will you get 220volts? a 144volt pack takes a lot of real estate, and
packs a lot of weight.
>
> I think a solid state vibrator can easily be built
> to convert 220 DC to 220 AC three phase.
> A sucessful car like this would go a long way
> in making PV more useful in reducing oil usage.
successful would be the key phrase ....
>
> Joe Fischer
>
--
Steve Spence
www.green-trust.org
Joe Fischer
>"Joe Fischer" wrote:
>> I am getting impatient waiting for a hybrid car
>> with some PV on the top. If a motor manufacturer
>> is not going to produce a low cost 20 horse DC motor,
>> then there should be a grass roots effort to take
>> front wheel drive cars and put two 220 volt 20 HP
>> 3 phase motors in the front, one to each front wheel.
>> I would also like to see a car like that with
>> a third motor driving the rear wheels.
>
>There is not enough real estate on top of a car to make pv more than a
>trickle charger.
Maybe my cars are bigger than your cars. :-) I think
I could fit at least 6 square meters of cells on each of mine.
>What will 20hp do for you?
With three 20 hp motors the average mid size car
would do pretty good, a 4 liter motor does good to produce
40 horsepower at less than 2000 RPM.
>Where will you get 220volts? a 144volt pack takes a lot of real estate, and
>packs a lot of weight.
18 or 19 12 volt batteries, a hybrid doesn't need more
than a couple of minutes at full load.
It seems some of the hybrid attempts tried to use both
the electric motor and the IC engine to power the car.
>> I think a solid state vibrator can easily be built
>> to convert 220 DC to 220 AC three phase.
>> A sucessful car like this would go a long way
>> in making PV more useful in reducing oil usage.
>
>successful would be the key phrase ....
Of course, but the first car with the right design
comes first, trying to do electric vehicles with one big
motor is silly, cruising doesn't take as much power as
accelerating.
Do you think that they can build solar powered
airplanes that can fly to 20 kilometers altitude, but solar
would not help a car at all?
Joe Fischer
Steve Spence
> On Sun, 19 "Steve Spence" <ssp...@green-trust.org> wrote:
>
> >"Joe Fischer" wrote:
> >> I am getting impatient waiting for a hybrid car
> >> with some PV on the top. If a motor manufacturer
> >> is not going to produce a low cost 20 horse DC motor,
> >> then there should be a grass roots effort to take
> >> front wheel drive cars and put two 220 volt 20 HP
> >> 3 phase motors in the front, one to each front wheel.
> >> I would also like to see a car like that with
> >> a third motor driving the rear wheels.
> >
> >There is not enough real estate on top of a car to make pv more than a
> >trickle charger.
>
> Maybe my cars are bigger than your cars. :-) I think
> I could fit at least 6 square meters of cells on each of mine.
That's only 500 watts or so. Trickle chargers.
>
> >What will 20hp do for you?
>
> With three 20 hp motors the average mid size car
> would do pretty good, a 4 liter motor does good to produce
> 40 horsepower at less than 2000 RPM.
60hp is 46kw. you only have 500 watts of pv. see a problem here?
>
> >Where will you get 220volts? a 144volt pack takes a lot of real estate,
and
> >packs a lot of weight.
>
> 18 or 19 12 volt batteries, a hybrid doesn't need more
> than a couple of minutes at full load.
> It seems some of the hybrid attempts tried to use both
> the electric motor and the IC engine to power the car.
these batteries weigh over 50lbs each. think again.
Joe Fischer
>On Sun, 19 Oct 2003 23:38:06 -0400, Joe Fischer wrote:
>Steve is right, even at 6 m^2 of cells you're looking at several days
>(at least) to recharge the battery pack. If that's not a trickle
>charger, I don't know what is. A PV trickle charger may or may not be a
>desirable feature, but it's still a trickle charger.
A hybrid is intended to use the IC engine to recharge the
batteries, the solar would just be for assuring a top charge the
same way a float charger works.
And 500 watts on a good sunny day could allow going
a couple of miles to the store without using much gasoline.
Solar PV can be used on vehicles with additional stationary
panels at home or business parking. Oil will definitely be a
serious problem within the lifetimes of young people living today,
so every little advantage must be taken as soon as possible,
before it becomes a crisis situation.
The price of oil is very crucial to the rate of development
of solar PV. Being pessimistic only retards development.
I think solar PV holds more promise for automobiles
than nuclear energy held for atomic powered aircraft.
A 3000 horsepower aircraft engine (like one I worked
on in 1946) is equivalent to about 2 megawatts, and large aircraft
had 4 or 6 of those.
Yet designs for the airborne reactor only planned for
a couple of megawatts, not even close to enough.
A few years ago an engineer working on fuel cells
asked for information in an aviation newsgroup, he was
planning on designing a 700kw fuel cell to power a 737,
which wouldn't be much more than an aux. power unit.
Many cars never go more than 20 miles from home,
and solar PV could possibly be used at both ends of the trip
in addition to the PV on the top of the car.
Waiting till gas prices reach $3.00 a gallon will leave
a lot of people in big trouble (does anybody pay close to $3.00
now in some places?).
I have repeatedly been told that engineering is meant
to get the last few percent in efficiency, and it is obvious there
is a lot of percents to be gained in hybrid vehicle technology,
and solar PV can, and will have to, play a role.
Continuing the one motor, one car approach is obviously
not good engineering. In 1946 a 1940 Plymouth with all seats
and chrome removed, with high pressure bald tires, and the
accelerator pump removed from the carb, got over 100 MPG
in test runs, using powered acceleration and long coasts.
The average power could be applied with a smaller
engine to have a more constant speed, the very reason for
the coasting was because the regular car engine could not
be run at all over the whole trip, it had to have the fuel
flow shut off while coasting.
This is important to consider in a hybrid vehicle,
and every watt that can be developed without using fuel
will help make the design feasible.
Solar PV must be developed to replace power at
a certain cost, and the time is approaching when those
costs will be right.
In 1970 fleet gasoline was 11 cents per gallon for
cab companies that paid the road taxes by the mile, so
PV was not even worth thinking about then.
But a calculation of gas prices now will show
a completely different story.
There are all kinds of garage workshops being
shown as contests on TV, but none even approach the
good engineering applications of multiple electric
motors to a 3000 pound car.
The motor in my car plus a full gas tank weighs
about 1000 pounds, so the batteries for a hybrid are not
out of the question.
The thinking just needs to change, and include
PV as a part of the long range planning.
Vehicle fuel and space heating are two of the biggest
energy needs in the world, and 500 watts for 6 or 7 hours on
a good sunny day is 4 or 5 horsepower hours, and that is worth
thinking about.
It does not require energy to move sustain motion
on level ground other than air resistance and rolling friction.
Joe Fischer
Jeff
"Steve Spence" <ssp...@green-trust.org> wrote in message
news:3f927...@newsfeed.slurp.net...
> "Joe Fischer" <gravity...@ig1ou.com> wrote in message
> news:bbl6pvkqamp8k1ods...@4ax.com...
> > On Sun, 19 "Steve Spence" <ssp...@green-trust.org> wrote:
> >
> > >"Joe Fischer" wrote:
> > >> I am getting impatient waiting for a hybrid car
> > >> with some PV on the top. If a motor manufacturer
> > >> is not going to produce a low cost 20 horse DC motor,
> > >> then there should be a grass roots effort to take
> > >> front wheel drive cars and put two 220 volt 20 HP
> > >> 3 phase motors in the front, one to each front wheel.
> > >> I would also like to see a car like that with
> > >> a third motor driving the rear wheels.
> > >
> > >There is not enough real estate on top of a car to make pv more than a
> > >trickle charger.
> >
> > Maybe my cars are bigger than your cars. :-) I think
> > I could fit at least 6 square meters of cells on each of mine.
>
> That's only 500 watts or so. Trickle chargers.
Wrong. A electric car (GM's EV1 before they were destroyed) gets 120 miles
(193 km) to 16.9 kw/h (the batteries range when fitted with the original
lead acid batteries). Breaking that down gives about 87W/h per km. Assuming
the cells get 5 good hours of light a day (or a lot of moderate light), that
generates 2.5 kw/h per day, which is about 31 km's. That's some trickle
charger. Now, most electric cars may not be as efficient, but not far off
from that. I have calculated a typical high efficiency gas car to use about
150 W/h per km at the flywheel, which has many other parasitic loads such as
alternator, water pump, power steering, much more complex drive train, runs
when idle, needs to warmed up, FI and ign needs considerable energy, no
regenitive braking, poorer aerodynamics, etc so this is a very reasonable
number. Now, the biggest thing, is I don't see where 500 W of panels would
fit on a typical car unless it was a large station wagon. Panels imbedded
into the hood might posess quite a ascetics challenge, so the roof would be
the main collection area. Window tint could also be made with solar cell
technology.
BTW, a electric motor is rated different from an gasoline engine. a 20 hp
electric motor can produce 60 to 80 hp bursts of power, often much more. A
gasoline engine is rated at it's peak power. A 100 hp gasoline engine will
produce a maximum of 100 hp, and would self destruct in a short time if run
at full power continuously. GM's EV1 produced something like 140 hp or kw/h
of energy to the wheels. It was faster accelerating then most gas powered
cars (remember an electric motor is almost always in it's peak power range
and efficiency, where a gasoline almost never is), and a non governed
prototype hit 183 miles an hour.
>
> >
> > >What will 20hp do for you?
> >
> > With three 20 hp motors the average mid size car
> > would do pretty good, a 4 liter motor does good to produce
> > 40 horsepower at less than 2000 RPM.
At wide open thottle.
>
> 60hp is 46kw. you only have 500 watts of pv. see a problem here?
No, I don't. Read above. 60 Hp is not needed to maintain speed, only for
accelerating. Unless you plain on going down a highway at 200 km/h, or going
up huge hills (don't forget regenitive braking on the way down restores most
of the energy lost), 60+ hp would only be needed for a few seconds.
If the car drives 10 km, then 0.87 kw/h was consumed. Since 1 hp used for 1
h is 0.746 kw/h, and the car takes 1 hour to get there (10km/h), then only
1.16 hp is required to maintain speed. (note, assuming 100% electrical to
mechanical energy conversion - real case is usually better then 90%, and
since the 0.087 is a real number, the hp requirements would slightly
decrease). At 100 km/h, for 1 hour, 8.7kw/h would be consumed, and would
require a 11.6 hp source to maintain speed.
Note, this is neglecting the fact that air friction is a function of speed
squared, ie the faster you go, the air resistance increases at a rate of a
constant times the speed, and times the speed again. This means that the
force slowing the car down from air friction is about 100 times greater at
100 km/h, then it is at 10 km/h. GM's EV1 was likely rated at a reasonable
speed of 50 to 70 km/h. This means the above simple calculations mean that
the required hp level at 10 km/h is much lower then calculated, and higher
at fast highway speeds.
>
> >
> > >Where will you get 220volts? a 144volt pack takes a lot of real estate,
> and
> > >packs a lot of weight.
Ever stick together 10 to 20 9V alkaline batteries - that will produce
about 90 to 180 volts. Voltage is not a measure of battery size. Storage
capacity is.
> >
> > 18 or 19 12 volt batteries, a hybrid doesn't need more
> > than a couple of minutes at full load.
> > It seems some of the hybrid attempts tried to use both
> > the electric motor and the IC engine to power the car.
>
> these batteries weigh over 50lbs each. think again.
GM's EV1 had 16.9 kw/h of storage with the old lead acid batteries before
they switched over to NiMH, which brought the mileage up to 18- miles from
120. The lead acid battery bank weighed about 1500 lbs, if a remember
correctly. The voltage is in the order of 320 V.
>
> >
> > >> I think a solid state vibrator can easily be built
> > >> to convert 220 DC to 220 AC three phase.
Properly called an inverter. For a motor drive its called a VFD, short for
variable frequency drive. DC motors are outdated by this technology that is
more efficient, easier to control, and has nothing like commutators and
brushes to wear out. The motors are also very simple (although more complex
to understand, and the internal electronics are very complex, but easily
handled by cheap microprocessors).
> > >> A sucessful car like this would go a long way
> > >> in making PV more useful in reducing oil usage.
> > >
> > >successful would be the key phrase ....
> >
> > Of course, but the first car with the right design
> > comes first, trying to do electric vehicles with one big
> > motor is silly,
Why? Separate motors do have their advantages for all when drive and
handling purposes, but for an every day generally vehicle, there is no need.
I like high performance driving, so I would prefer separate control on al
the wheels, but for the average 95% who want to get groceries and go to work
with their car, along with taking the family to uncle Bob's house don't care
for that much, especially if it adds more cost.
Jeff
> On Mon, 20 R. H. Allen <kka...@REMOVEhotmail.com> wrote:
>
> >On Sun, 19 Oct 2003 23:38:06 -0400, Joe Fischer wrote:
>
> >Steve is right, even at 6 m^2 of cells you're looking at several days
> >(at least) to recharge the battery pack. If that's not a trickle
> >charger, I don't know what is. A PV trickle charger may or may not be a
> >desirable feature, but it's still a trickle charger.
See my other post on this subject! At 0.087 kw/h per km (GM's EV1), a 500W
panel would do well, if you could fit it.
Jeff
"Rusty Shackleford" <RUS...@sbcglobal.net> wrote in message
news:mri4tvk98ddu599ue...@4ax.com...
> On Sat, 06 Dec 2003 09:25:23 GMT, "Jeff" <levy...@hotmail.com>
> wrote:
>
>
> >Wrong. A electric car (GM's EV1 before they were destroyed) gets 120
miles
> >(193 km) to 16.9 kw/h (the batteries range when fitted with the original
> >lead acid batteries).
> "Expected real-world range was 55-95 miles for the high-capacity
> lead-acid EV1." That's 88-153 km.
> The battery capacity was 18.7 kwh. (You can't even get the units
> right)
Actually, the numbers I gave were from differnt sources, after reading many
reveiw awhile back.I "KNOW" I read on several sites that the 25 kwh NiMh
battery bank range was typically up to 180 miles. Now that i think about it
some more, the EV1 had 3 battery revisions. The original was 16.9 kwh lead
acid, then a high capcity lead acid, then the HiMh. Sorry about the units, I
had a long sleepless night and was not thinking about the units when posted,
although I did notice something did not look right.
>
> >Breaking that down gives about 87W/h per km.
> Wrong again. Try 122 Wh/km to 212 Wh/km. Note the correct units as
> well.
OK, even so if I was 40 to 243% off (that must be one big hill it was
climbing at highway speeds for that drop to 212 Wh/km efficiency. A gas car
would do just as bad), the point is still vaild, just not as much so.
>
> >Assuming
> <<snip>>
> Why bother, your basing everything else on this crap. Care to try
> again?
>
Sure! at the numbers you gave, the 2.5kWh/day gives between 11.8 and 20.5 km
extra range for free per day. That's not neglectable.
>
> >the cells get 5 good hours of light a day (or a lot of moderate light),
that
> >generates 2.5 kw/h per day, which is about 31 km's. That's some trickle
> >charger. Now, most electric cars may not be as efficient, but not far off
> >from that. I have calculated a typical high efficiency gas car to use
about
> >150 W/h per km at the flywheel,
> You did that wrong as well. See
> v284tvoo825n5135h...@4ax.com
That's a emal address or something.
>
> >which has many other parasitic loads such as
> >alternator, water pump, power steering, much more complex drive train,
runs
> >when idle, needs to warmed up, FI and ign needs considerable energy, no
> >regenitive braking, poorer aerodynamics, etc so this is a very reasonable
> >number.
> Wrong again. You based your number on fuel used per mile, so all
> parasitic loads were included.
I was tring to show how large the parasitic drains were. Sure the output
from the engine is higher, but what you actually get to use is much less.
These loads are not present on a EV. I'll do a quick calc for you: Car uses
0.1 L /km (typical good economy car 10 L per 100 km), 38,000 kj/L of
gasoline = 3,800 kj/km. Assuming 20% real efficiency (25% is not reached
often in reality for a significant amount of time in a ICE), 760 kj/km are
output from the engine. This corrisponds to 211 Wh/km. Now subtract 15 to
30A @ 13.8 V = 200 W to 400W to maintain the fuel injection and ign system
not present on a EV, another 500 to 2000 W for the water pump, another 300 W
for the power steering pump on avgerage, several times more drive train loss
(no transmission needed in a EV), lower arowdynamics due to better design
(EV's take care of his, and it could be done to ICE cars). All these
parasitics not present on a EV can easily add up to 30 to 80 wh/km, possibly
much more.
>
>
> >BTW, a electric motor is rated different from an gasoline engine. a 20 hp
> >electric motor can produce 60 to 80 hp bursts of power, often much more.
A
> >gasoline engine is rated at it's peak power. A 100 hp gasoline engine
will
> >produce a maximum of 100 hp, and would self destruct in a short time if
run
> >at full power continuously.
> Bullshit.
OK, prove it.
For some reason I doubt most cars would last long at wide open throttle at
5,500 to 6,500 rpm, assuming they are on a safe road like a race track. I
doubt a brand new car would reach 10,000 km's before a major engine failure
like rod bearings or burnt valves would happen. Electric motors ARE rated
differntly.
>
> >GM's EV1 produced something like 140 hp or kw/h
> >of energy to the wheels.
> 140 hp or kw/h? Are you saying 1 hp=1Kwh?
No, 1hp = 746 W. I couldn't remember which the EV was rated in. It is 140
hp.
> Your units don't match up,
> nor do the numbers. Further, the power rating you cite was for the
> motor, the power measured at the wheels is less.
This is why I used the power avalible from the flywheel, after all the
inherent ICE parasitics are removed, that's actually used to move the
gasoline car. The electric car has at least a 90% electric to mechanical
conversion efficiency, so the numbers should be simular.
>
> >It was faster accelerating then most gas powered
> >cars
> 0-60 mph in 9 seconds? I hardly think so.
Mid range performance. Off the get go it is kind of slow.
>
> >(remember an electric motor is almost always in it's peak power range
> >and efficiency, where a gasoline almost never is), and a non governed
> >prototype hit 183 miles an hour.
> LOL, there was much more to that prototype than just a lack of a
> governor.
Yes, it did have many mods, but the drive train was nearly identical. They
were pushing the motor to it's limits. Thermal problems were the real
limiting factor.It's real signifigance is that a EV is capable of that
speed. A much more impressive vehical is the T zero discussed in the link
below.
>
> Jeff, do you just make this stuff up? Exactly what is the source of
> your information?
Many a web site on the EV1 about 5 months ago. I still have some links
somewhere - I'll see if I an find them.
And here is a link for you to check out - A electric car will do 0 to 60 MPH
in 3.6 seconds!, gets 160 Wh/km at 60 MPH, (remember, speed carries a V^2
term!), and a range at this speed of over 300 miles. Also contains much
other good info. Those RAV4's were pigs on power!
http://www.acpropulsion.com/EAASV_101803.pdf
One other thing, batteries of today can easily be charged in 1 to 2 hours
from dead to almost full, it just requires enough energy to do it. Faster
charging migh pose some problems, like heat build up. Slower charging is a
little easier on the batteries, and most batteries charge up to about 80 %
rapidly, and the rest takes a while.
>
>
K. Jones
"Jeff" <levy...@hotmail.com> wrote in message
news:_YtAb.6245$IF6.2...@ursa-nb00s0.nbnet.nb.ca...
>
> "Rusty Shackleford" <RUS...@sbcglobal.net> wrote in message
> news:mri4tvk98ddu599ue...@4ax.com...
> > On Sat, 06 Dec 2003 09:25:23 GMT, "Jeff" <levy...@hotmail.com>
> > wrote:
> > >BTW, a electric motor is rated different from an gasoline engine.
How do you figure that?
>a 20 hp
> > >electric motor can produce 60 to 80 hp bursts of power, often much
more.
Really? Cite please.
(you do know what the "service factor" on an electric motor nameplate is,
right?)
> A
> > >gasoline engine is rated at it's peak power. A 100 hp gasoline engine
> will
> > >produce a maximum of 100 hp, and would self destruct in a short time if
> run
> > >at full power continuously.
> > Bullshit.
>
> OK, prove it.
Ummm, no. You made the claim, it's up to you to prove it.
> For some reason I doubt most cars would last long at wide open throttle at
> 5,500 to 6,500 rpm, assuming they are on a safe road like a race track. I
> doubt a brand new car would reach 10,000 km's before a major engine
failure
> like rod bearings or burnt valves would happen. Electric motors ARE rated
> differntly.
Rated differently? Could you explain that better?
K. Jones
Jeff
"K. Jones" <shadet...@hotmailNODAMNSPAM.com> wrote in message
news:3HjBb.374$tk1.1...@news20.bellglobal.com...
>
> "Jeff" <levy...@hotmail.com> wrote in message
> news:_YtAb.6245$IF6.2...@ursa-nb00s0.nbnet.nb.ca...
> >
> > "Rusty Shackleford" <RUS...@sbcglobal.net> wrote in message
> > news:mri4tvk98ddu599ue...@4ax.com...
> > > On Sat, 06 Dec 2003 09:25:23 GMT, "Jeff" <levy...@hotmail.com>
> > > wrote:
> > > >BTW, a electric motor is rated different from an gasoline engine.
>
> How do you figure that?
2nd link from a google serch:
http://www.austinev.org/evalbum/motor.html
Here's a small motor:
http://www.cloudelectric.com/item.html?PRID=735634
Here's larger motors:
http://www.electroauto.com/catalog/motors.shtml
>
> >a 20 hp
> > > >electric motor can produce 60 to 80 hp bursts of power, often much
> more.
There are racing EV motors that produce a much bigger peak then that
(something like a 10 or 11 times factor). They however run coolant through
them. I think some were rated over 350 HP peak, IIRC.
>
> Really? Cite please.
> (you do know what the "service factor" on an electric motor nameplate is,
> right?)
Look here:
http://www.electroauto.com/catalog/motors.shtml
We're not talking cheap fractional HP commercial motors here, and even those
can produce more HP then rated for short periods of time.
>
> > A
> > > >gasoline engine is rated at it's peak power. A 100 hp gasoline engine
> > will
> > > >produce a maximum of 100 hp, and would self destruct in a short time
if
> > run
> > > >at full power continuously.
> > > Bullshit.
> >
> > OK, prove it.
>
> Ummm, no. You made the claim, it's up to you to prove it.
See below - If you run your gasoline engine like that, expect to replace it
quite often. Even running a car at really high RPM's at light throttle will
kill a engine in short order, muchless wide open at high RPM's.
>
>
> > For some reason I doubt most cars would last long at wide open throttle
at
> > 5,500 to 6,500 rpm, assuming they are on a safe road like a race track.
I
> > doubt a brand new car would reach 10,000 km's before a major engine
> failure
> > like rod bearings or burnt valves would happen. Electric motors ARE
rated
> > differntly.
>
> Rated differently? Could you explain that better?
When was the last time you heard of a gasoline engine rated for 200 HP
giving more then that? Most gasoline engines have a problem even making the
claimed HP. One other intereresting thing between electric and gas motors is
that the electric motor is always in it's peak power, where a gas motor is
not. This means that a smaller electric motor can do the same acceleration
as a large gas motor. See AC propulsion's T zero
http://www.acpropulsion.com/ - it has a 150 kw peak power electric motor
(~200 hp), and it woops Corvette's, Porsche's, Ferrari's, etc. It's even
faster now with Li ION batteries, and it can go 300 miles between recharges
@ 60 MPH http://www.acpropulsion.com/EAASV_101803.pdf
>
> K. Jones
>
>
K. Jones
>
>
> "K. Jones" <shadet...@hotmailNODAMNSPAM.com> wrote in message
> news:3HjBb.374$tk1.1...@news20.bellglobal.com...
> >
> > "Jeff" <levy...@hotmail.com> wrote in message
> > news:_YtAb.6245$IF6.2...@ursa-nb00s0.nbnet.nb.ca...
> > >
> > > "Rusty Shackleford" <RUS...@sbcglobal.net> wrote in message
> > > news:mri4tvk98ddu599ue...@4ax.com...
> > > > On Sat, 06 Dec 2003 09:25:23 GMT, "Jeff" <levy...@hotmail.com>
> > > > wrote:
> > > > >BTW, a electric motor is rated different from an gasoline engine.
> >
> > How do you figure that?
>
>
> 2nd link from a google serch:
>
> http://www.austinev.org/evalbum/motor.html
This guys opinion. Not exactly a valid cite.
However,
Intermittant duty vs continious duty.
The type of duty is usually available in the motor literature.
Auto manufacturers also cite HP @ 'X' rpm, and state that it's peak HP when
so.
What is the difference?
Shaft HP is no different than shaft HP......
> Here's a small motor:
>
> http://www.cloudelectric.com/item.html?PRID=735634
>
> Here's larger motors:
>
> http://www.electroauto.com/catalog/motors.shtml
>
> >
> > >a 20 hp
> > > > >electric motor can produce 60 to 80 hp bursts of power, often much
> > more.
>
> There are racing EV motors that produce a much bigger peak then that
> (something like a 10 or 11 times factor). They however run coolant through
> them. I think some were rated over 350 HP peak, IIRC.
>
Ohhhh, "special _racing_ motors". Hmmm, apples to apples then.
My ICE peak HP is 275.....except when I flip the switch and throw _roughly_
a 100 HP shot of NOS on it....then it's closer to 400HP.....
"in bursts". Sure isn't going to last all day running like that, neither is
a 20HP electric motor likely to last very long when stressed beyond design.
What is the difference?
> >
> > Really? Cite please.
> > (you do know what the "service factor" on an electric motor nameplate
is,
> > right?)
>
> Look here:
>
> http://www.electroauto.com/catalog/motors.shtml
>
> We're not talking cheap fractional HP commercial motors here, and even
those
> can produce more HP then rated for short periods of time.
Basically any "motor" can.
> >
> > > A
> > > > >gasoline engine is rated at it's peak power. A 100 hp gasoline
engine
> > > will
> > > > >produce a maximum of 100 hp, and would self destruct in a short
time
> if
> > > run
> > > > >at full power continuously.
> > > > Bullshit.
> > >
> > > OK, prove it.
> >
> > Ummm, no. You made the claim, it's up to you to prove it.
>
> See below - If you run your gasoline engine like that, expect to replace
it
> quite often. Even running a car at really high RPM's at light throttle
will
> kill a engine in short order, muchless wide open at high RPM's.
>
> >
> >
> > > For some reason I doubt most cars would last long at wide open
throttle
> at
> > > 5,500 to 6,500 rpm, assuming they are on a safe road like a race
track.
Hang on. You're talking about "special racing electric motors".
Thousands of "race ICE's" will run 5,500 to 6,400 rpm all day long.
What is the difference?
I
> > > doubt a brand new car would reach 10,000 km's before a major engine
> > failure
> > > like rod bearings or burnt valves would happen. Electric motors ARE
> rated
> > > differntly.
I doubt your 20HP electric motor would reach 10,000km's when run at
"60 or 80HP" before a major failure.
What is the difference?
> > Rated differently? Could you explain that better?
>
> When was the last time you heard of a gasoline engine rated for 200 HP
> giving more then that?
How old are you? Lots and lots. It was routine for manufactures to, ummm,
"understate" the HP of many, many muscle cars.
>Most gasoline engines have a problem even making the
> claimed HP.
*SOME*, and only by cheap import manufactures. ASME is working on a
standard to eliminate this kind of "false advertising".
>One other intereresting thing between electric and gas motors is
> that the electric motor is always in it's peak power,
Say again? What kind of electric motor is "always in it's peak
power"...regardless of speed or load?
The cite for this should prove interesting!
where a gas motor is
> not. This means that a smaller electric motor can do the same acceleration
> as a large gas motor. See AC propulsion's T zero
> http://www.acpropulsion.com/ - it has a 150 kw peak power electric motor
> (~200 hp), and it woops Corvette's, Porsche's, Ferrari's, etc. It's even
> faster now with Li ION batteries, and it can go 300 miles between
recharges
> @ 60 MPH http://www.acpropulsion.com/EAASV_101803.pdf
I'm not trying to "rain on your parade", or dampen your enthusiasm for EV's.
Just trying to get you to tone down your wild claims, that are "all over the
map"
K. Jones
Jeff
"K. Jones" <shadet...@hotmailNODAMNSPAM.com> wrote in message
>
> "Jeff" <levy...@hotmail.com> wrote in message
> news:YOmBb.8280$IF6.3...@ursa-nb00s0.nbnet.nb.ca...
> >
> >
> > "K. Jones" <shadet...@hotmailNODAMNSPAM.com> wrote in message
> > news:3HjBb.374$tk1.1...@news20.bellglobal.com...
> > >
> > > "Jeff" <levy...@hotmail.com> wrote in message
> > > news:_YtAb.6245$IF6.2...@ursa-nb00s0.nbnet.nb.ca...
> > > >
> > > > "Rusty Shackleford" <RUS...@sbcglobal.net> wrote in message
> > > > news:mri4tvk98ddu599ue...@4ax.com...
> > > > > On Sat, 06 Dec 2003 09:25:23 GMT, "Jeff" <levy...@hotmail.com>
> > > > > wrote:
> > > > > >BTW, a electric motor is rated different from an gasoline engine.
> > >
> > > How do you figure that?
> >
> >
> > 2nd link from a google serch:
> >
> > http://www.austinev.org/evalbum/motor.html
>
> This guys opinion. Not exactly a valid cite.
Do a serch under google - there should be ton of refernces.
>
> However,
> Intermittant duty vs continious duty.
> The type of duty is usually available in the motor literature.
>
> Auto manufacturers also cite HP @ 'X' rpm, and state that it's peak HP
when
> so.
Not anymore, as you also noted. See below. big numbers help sell stuff (to
morons!), and lying about hp makes bigger numbers.
> What is the difference?
> Shaft HP is no different than shaft HP......
Yes, that is true, however the electric motors can be safely "overpowered"
for several minutes. That may be a better term to discribe it. Gasoline
motors produce their max hp, and that's it - you cant produce any more
without modifications. There is another thing about more efficient use of
torque, discussed below.
>
>
>
> > Here's a small motor:
> >
> > http://www.cloudelectric.com/item.html?PRID=735634
> >
> > Here's larger motors:
> >
> > http://www.electroauto.com/catalog/motors.shtml
Did you look at that last site? It's a EV motor manufacture.
> >
> > >
> > > >a 20 hp
> > > > > >electric motor can produce 60 to 80 hp bursts of power, often
much
> > > more.
> >
> > There are racing EV motors that produce a much bigger peak then that
> > (something like a 10 or 11 times factor). They however run coolant
through
> > them. I think some were rated over 350 HP peak, IIRC.
> >
> Ohhhh, "special _racing_ motors".
The others are not racing motors. That was just one extreme example dumping
in more then 10 times the continuous rating.
>Hmmm, apples to apples then.
> My ICE peak HP is 275.....except when I flip the switch and throw
_roughly_
> a 100 HP shot of NOS on it....then it's closer to 400HP.....
Fine. But normally, like when driving down a highway, it is moving your car
with 20 to 40 hp. Anything more then that is not continuous. I doubt you use
275 or more HP for more then a minute or two?
> "in bursts". Sure isn't going to last all day running like that, neither
is
> a 20HP electric motor likely to last very long when stressed beyond
design.
> What is the difference?
The electric motors are designed for it. The only stress is heat build up,
unlike a ICE. Heat build up reduces the permeability of magnetic materials,
and therefore the power drops. If the heat gets too serious, the windings
can become damaged. In an 3 phase motor, the only moving part is a iron
core - hardly anything to break.
Look at this EV motor manufactures ratings. This is typical of other
electric motor manufactures, however they are usually rated in kW usually
with a max rating and a continuous rating.
http://www.electroauto.com/catalog/motors.shtml
Some EV motors, mostly the AC ones are starting to rate their motors in peak
power, and have a continuous rating. This is a smart move, since people are
accustomed to peak power ratings. www.acpropulsion.com rates their AC-150
drive at 150 kW peak (which is several minutes), and 50 kW continuous (in
one of their spec shhets or white papers).
>
> > >
> > > Really? Cite please.
> > > (you do know what the "service factor" on an electric motor nameplate
> is,
> > > right?)
> >
> > Look here:
> >
> > http://www.electroauto.com/catalog/motors.shtml
> >
> > We're not talking cheap fractional HP commercial motors here, and even
> those
> > can produce more HP then rated for short periods of time.
> Basically any "motor" can.
A ICE can not produce more power then it's rated for, unless mods are done
to it.
An electric motor is rated for a continuous power, and safely overload for
several minutes.
It''s just differnt ratings. It would be MUCH less confusing to use the peak
HP for each, however there are good reasons for the ratings.
>
> > >
> > > > A
> > > > > >gasoline engine is rated at it's peak power. A 100 hp gasoline
> engine
> > > > will
> > > > > >produce a maximum of 100 hp, and would self destruct in a short
> time
> > if
> > > > run
> > > > > >at full power continuously.
> > > > > Bullshit.
> > > >
> > > > OK, prove it.
> > >
> > > Ummm, no. You made the claim, it's up to you to prove it.
> >
> > See below - If you run your gasoline engine like that, expect to replace
> it
> > quite often. Even running a car at really high RPM's at light throttle
> will
> > kill a engine in short order, muchless wide open at high RPM's.
> >
> > >
> > >
> > > > For some reason I doubt most cars would last long at wide open
> throttle
> > at
> > > > 5,500 to 6,500 rpm, assuming they are on a safe road like a race
> track.
>
> Hang on. You're talking about "special racing electric motors".
No, I'm not - I just referred to a special racing motor that pushed it to
the extremes. A 3 to 4 times the continuous power rating is typical.
> Thousands of "race ICE's" will run 5,500 to 6,400 rpm all day long.
> What is the difference?
And they get rebuilt after a few good races, depending on how well they are
built, and how hard they are stressed. Not really relivent anyway, same as
the racing motor I pointed out.
>
> I
> > > > doubt a brand new car would reach 10,000 km's before a major engine
> > > failure
> > > > like rod bearings or burnt valves would happen. Electric motors ARE
> > rated
> > > > differntly.
> I doubt your 20HP electric motor would reach 10,000km's when run at
> "60 or 80HP" before a major failure.
> What is the difference?
>
> > > Rated differently? Could you explain that better?
> >
> > When was the last time you heard of a gasoline engine rated for 200 HP
> > giving more then that?
>
> How old are you? Lots and lots. It was routine for manufactures to,
ummm,
> "understate" the HP of many, many muscle cars.
Muscle cars, Too bad I was not around for them. They were gone for decades.
Newer cars are not rated the same. Looks like you know what I mean from what
you wrote below, however since numbers sell, all the manufactures have to
lie at least a bit - high performance cars are generally a little more
accurate (but then the Camaro's and Firebirds had a slightly lower power
rating then the Corvettes with the same engine (same heads, cam, dual cat,
everything). Go figure). High performance cars used to be underrated power
wise, along with the speedometer, to help offset insurance costs.
>
>
> >Most gasoline engines have a problem even making the
> > claimed HP.
>
> *SOME*, and only by cheap import manufactures. ASME is working on a
> standard to eliminate this kind of "false advertising".
>
> >One other intereresting thing between electric and gas motors is
> > that the electric motor is always in it's peak power,
>
> Say again? What kind of electric motor is "always in it's peak
> power"...regardless of speed or load?
> The cite for this should prove interesting!
Check out the Tzero at AC propulsion's website. It's rated for 200 HP PEAK
(67 hp continuous), woops Corvettes, Ferrari's, Porsche's, Lamborghinis, and
with the LiION battery pack, it does 0 -60 MPH in 3.6 seconds, with a 300
mile range at 60 MPH.
http://www.acpropulsion.com/EAASV_101803.pdf
The reason is the electric motor produces a high, continuous torque over
most of it's power range. A gasoline engine produces a high amount of torque
over a small RPM range, and when you switch gears it produces a fraction of
the torque to the wheels. Torque is what moves a vehicle, and is related to
F=MA, where F = force, from the tires converting the torque to force, M =
mass of the vehicle, and A = acceleration.. Solving for A = F/M, so clearly
increasing the torque will increase the force, and thus the acceleration.
http://www.acpropulsion.com/PDF%20files/Living%20with%20an%20EV.pdf - see
section 2.4, as it has a nice torque curve of a electric, vs gas. (BTW, if
the car had 200 hp of power on take off, that sloped line would continue up
to the y axis of the graph, so it's not using the full 200 hp until some
time down the road)
>
> where a gas motor is
> > not. This means that a smaller electric motor can do the same
acceleration
> > as a large gas motor. See AC propulsion's T zero
> > http://www.acpropulsion.com/ - it has a 150 kw peak power electric motor
> > (~200 hp), and it woops Corvette's, Porsche's, Ferrari's, etc. It's even
> > faster now with Li ION batteries, and it can go 300 miles between
> recharges
> > @ 60 MPH http://www.acpropulsion.com/EAASV_101803.pdf
>
> I'm not trying to "rain on your parade", or dampen your enthusiasm for
EV's.
> Just trying to get you to tone down your wild claims, that are "all over
the
> map"
Unfortunately, they are not wild claims - just a different industry ;-(
>
> K. Jones
>
>
K. Jones
>
> "K. Jones" <shadet...@hotmailNODAMNSPAM.com> wrote in message
> news:8SqBb.1827$tk1.4...@news20.bellglobal.com...
<snip>
> > However,
> > Intermittant duty vs continious duty.
> > The type of duty is usually available in the motor literature.
> >
> > Auto manufacturers also cite HP @ 'X' rpm, and state that it's peak HP
> when
> > so.
>
> Not anymore, as you also noted. See below. big numbers help sell stuff (to
> morons!), and lying about hp makes bigger numbers.
Ummm, no. AFAIK, less than 1/2 dozen specific vehicles currently being
manufactured have, "questionable" HP ratings.
Don't take that as all or most. I simply stated there are a _few_
instanses.
> > What is the difference?
> > Shaft HP is no different than shaft HP......
>
> Yes, that is true, however the electric motors can be safely "overpowered"
> for several minutes. That may be a better term to discribe it. Gasoline
> motors produce their max hp, and that's it - you cant produce any more
> without modifications. There is another thing about more efficient use of
> torque, discussed below.
Either you didn't read anything I wrote earlier, or we have a comprehension
problem.
HP=HP. Stating a continious duty number (and saying so), and stating a peak
number (and saying so), isn't "rating them differently".
<snip>
> > > There are racing EV motors that produce a much bigger peak then that
> > > (something like a 10 or 11 times factor). They however run coolant
> through
> > > them. I think some were rated over 350 HP peak, IIRC.
> > >
> > Ohhhh, "special _racing_ motors".
>
> The others are not racing motors. That was just one extreme example
dumping
> in more then 10 times the continuous rating.
>
> >Hmmm, apples to apples then.
> > My ICE peak HP is 275.....except when I flip the switch and throw
> _roughly_
> > a 100 HP shot of NOS on it....then it's closer to 400HP.....
>
> Fine. But normally, like when driving down a highway, it is moving your
car
> with 20 to 40 hp. Anything more then that is not continuous. I doubt you
use
> 275 or more HP for more then a minute or two?
Thirteen seconds+fraction, or 1/4 mile at a time, to be more specific
*smile*
I never claimed it took 275 HP to drive down the highway, why would you
imply that?
> > "in bursts". Sure isn't going to last all day running like that,
neither
> is
> > a 20HP electric motor likely to last very long when stressed beyond
> design.
> > What is the difference?
>
> The electric motors are designed for it. The only stress is heat build up,
> unlike a ICE. Heat build up reduces the permeability of magnetic
materials,
> and therefore the power drops. If the heat gets too serious, the windings
> can become damaged. In an 3 phase motor, the only moving part is a iron
> core - hardly anything to break.
You intall controllers, and wire/fuse at 20HP electric motor for 60/80HP
duty??
> Look at this EV motor manufactures ratings. This is typical of other
> electric motor manufactures, however they are usually rated in kW usually
> with a max rating and a continuous rating.
Exactly. The only difference is, auto manufactures don't give a "continious
rating", which would be much lower than the peak HP rating.
<snip>
> Muscle cars, Too bad I was not around for them. They were gone for
decades.
> Newer cars are not rated the same. Looks like you know what I mean from
what
> you wrote below, however since numbers sell, all the manufactures have to
> lie at least a bit - high performance cars are generally a little more
> accurate (but then the Camaro's and Firebirds had a slightly lower power
> rating then the Corvettes with the same engine (same heads, cam, dual cat,
> everything). Go figure). High performance cars used to be underrated power
> wise, along with the speedometer, to help offset insurance costs.
It's called "de-tuning". Many ice's are "de-tuned" at the factory for
various reasons. That's what keeps various "performance chip" manufactures
in business.
I suspect the reason cited above would be marketing. Don't wanna piss the
guys who are buying your "premium" sports car (the vette) off, by offering
as "powerful" a plant in the "cheapie" sports package now, do you? *smile*
<snip>
> > >One other intereresting thing between electric and gas motors is
> > > that the electric motor is always in it's peak power,
> >
> > Say again? What kind of electric motor is "always in it's peak
> > power"...regardless of speed or load?
> > The cite for this should prove interesting!
>
> Check out the Tzero at AC propulsion's website. It's rated for 200 HP PEAK
> (67 hp continuous), woops Corvettes, Ferrari's, Porsche's, Lamborghinis,
and
> with the LiION battery pack, it does 0 -60 MPH in 3.6 seconds, with a 300
> mile range at 60 MPH.
>
> http://www.acpropulsion.com/EAASV_101803.pdf
You didn't answer the question.
"What kind of electric motor is always in it's peak power, regardless of
speed or load?"
> The reason is the electric motor produces a high, continuous torque over
> most of it's power range. A gasoline engine produces a high amount of
torque
> over a small RPM range, and when you switch gears it produces a fraction
of
> the torque to the wheels. Torque is what moves a vehicle, and is related
to
> F=MA, where F = force, from the tires converting the torque to force, M =
> mass of the vehicle, and A = acceleration.. Solving for A = F/M, so
clearly
> increasing the torque will increase the force, and thus the acceleration.
????????
Torque: Something which produces or tends to produce rotation or torsion and
whos effectiveness is measured by the product of the force and the
perpendicular distance from the line of action of the force to the axis of
rotation.
> http://www.acpropulsion.com/PDF%20files/Living%20with%20an%20EV.pdf - see
> section 2.4, as it has a nice torque curve of a electric, vs gas. (BTW,
if
> the car had 200 hp of power on take off, that sloped line would continue
up
> to the y axis of the graph, so it's not using the full 200 hp until some
> time down the road)
??????
Are you talking about that messed up "tractive effort per vehicle weight"
graph?
What the hell is that?
"A gasoline engine produces a high amount of torque over a small rpm
range"???
Here are some _real_ engine dynographs
http://www.v8sho.com/SHO/dynographs.html
(I used to own a gen III V8SHO, what a fun car to drive!)
You can derive torque from HP and rpm, right?
<snip>
K. Jones
Jeff
"K. Jones" <shadet...@hotmailNODAMNSPAM.com> wrote in message
That is almost the entire problem - They don't say so.
There is one other thing about torque, which I will try to explain better
below.
>
>
> <snip>
>
> > > > There are racing EV motors that produce a much bigger peak then that
> > > > (something like a 10 or 11 times factor). They however run coolant
> > through
> > > > them. I think some were rated over 350 HP peak, IIRC.
> > > >
> > > Ohhhh, "special _racing_ motors".
> >
> > The others are not racing motors. That was just one extreme example
> dumping
> > in more then 10 times the continuous rating.
> >
> > >Hmmm, apples to apples then.
> > > My ICE peak HP is 275.....except when I flip the switch and throw
> > _roughly_
> > > a 100 HP shot of NOS on it....then it's closer to 400HP.....
> >
> > Fine. But normally, like when driving down a highway, it is moving your
> car
> > with 20 to 40 hp. Anything more then that is not continuous. I doubt you
> use
> > 275 or more HP for more then a minute or two?
>
> Thirteen seconds+fraction, or 1/4 mile at a time, to be more specific
> *smile*
Exactly. Good time! I managed to get into the high 14's once with a 2.8 L
MPFI 5 speed Camaro. Those little engines really like a lot more fuel and
ign timing then when delivered stock.
> I never claimed it took 275 HP to drive down the highway, why would you
> imply that?
Just to show that that 275 HP is not used much! Same as the full (peak)
power of an electric motor.
>
> > > "in bursts". Sure isn't going to last all day running like that,
> neither
> > is
> > > a 20HP electric motor likely to last very long when stressed beyond
> > design.
> > > What is the difference?
> >
> > The electric motors are designed for it. The only stress is heat build
up,
> > unlike a ICE. Heat build up reduces the permeability of magnetic
> materials,
> > and therefore the power drops. If the heat gets too serious, the
windings
> > can become damaged. In an 3 phase motor, the only moving part is a iron
> > core - hardly anything to break.
>
> You intall controllers, and wire/fuse at 20HP electric motor for 60/80HP
> duty??
There is a grammical error in there, but assuming you meant "wire a 20 HP
motor up for 60 to 80 HP", they, yes, that's what I mean. The motor can
handle that power for short duty cycles without damage, then backing it off
to the 20 HP level. This is easily done with PWM (Pulse Width Modulation)
techniques, which at full PWM duty cycle (duty cycle, as in the % that high
frequency electrical control pulses are on) is at full power. At 20% PWM
duty cycle, the motor is at approx 20% power. The controller is the key to
making this work. A AC motor using a simular setup just uses 3 PWM
controllers to generate the required 3 phase electrical needs.
>
> > Look at this EV motor manufactures ratings. This is typical of other
> > electric motor manufactures, however they are usually rated in kW
usually
> > with a max rating and a continuous rating.
>
> Exactly. The only difference is, auto manufactures don't give a
"continious
> rating", which would be much lower than the peak HP rating.
Now your understanding what I'm trying to say :-) "They" are not comparing
apples to apples.
>
> <snip>
>
> > Muscle cars, Too bad I was not around for them. They were gone for
> decades.
> > Newer cars are not rated the same. Looks like you know what I mean from
> what
> > you wrote below, however since numbers sell, all the manufactures have
to
> > lie at least a bit - high performance cars are generally a little more
> > accurate (but then the Camaro's and Firebirds had a slightly lower power
> > rating then the Corvettes with the same engine (same heads, cam, dual
cat,
> > everything). Go figure). High performance cars used to be underrated
power
> > wise, along with the speedometer, to help offset insurance costs.
>
> It's called "de-tuning". Many ice's are "de-tuned" at the factory for
> various reasons. That's what keeps various "performance chip"
manufactures
> in business.
A big chunk of those performance chips often suck! Some just tell the engine
it's running cold, and it goes into open loop operation with cold fuel
enrichment, screwing up the fuel injection system. All at a cost of $400 or
more, for a $4 chip. The other thing is it is set up to someone's test
engine, not your setup. Speed density systems (map sensor based) are very
sensitive to variations, unlike MAF based systems which are not that common
anymore due to expensive sensors. Of course there are exceptions, and most
brands seem to be getting better. I'd rather program my own to my engine and
parts, not someone else's "test" engine. check out www.diy-efi.org however
they experienced a huge crash a few months ago and are not fully up and
running again. Sorry for the off topic stuff - but you may enjoy it.
> I suspect the reason cited above would be marketing. Don't wanna piss the
> guys who are buying your "premium" sports car (the vette) off, by
offering
> as "powerful" a plant in the "cheapie" sports package now, do you? *smile*
Exactly - the programming in both computers was compared to be the same, and
the dyno results showed very close HP ratings, but the Corvette was always
rated at least 15 HP higher (Not really that significant anyway at 285 HP +,
unless racing). The Corvette is much lighter anyway, which does make a huge
difference.
>
> <snip>
>
> > > >One other intereresting thing between electric and gas motors is
> > > > that the electric motor is always in it's peak power,
> > >
> > > Say again? What kind of electric motor is "always in it's peak
> > > power"...regardless of speed or load?
> > > The cite for this should prove interesting!
> >
> > Check out the Tzero at AC propulsion's website. It's rated for 200 HP
PEAK
> > (67 hp continuous), woops Corvettes, Ferrari's, Porsche's, Lamborghinis,
> and
> > with the LiION battery pack, it does 0 -60 MPH in 3.6 seconds, with a
300
> > mile range at 60 MPH.
> >
> > http://www.acpropulsion.com/EAASV_101803.pdf
>
> You didn't answer the question.
>
> "What kind of electric motor is always in it's peak power, regardless of
> speed or load?"
Perhaps a bad choice of words - the torque of a electric motor (somewhat
dependant on motor design also) is VERY high at 0 RPM, and slowly decreases
with speed. This is perfect for accelerating a vehicle. With constant power
input, a torque curve output would basically look like a straight, sloping
down line on a graph of torque VS RPM. This is why that Tzero car can
accelerate faster then much higher powered cars. Torque is what moves a car,
the more you have, the faster you can accelerate ( Newton's law F = MA).
When bringing in RPM's with the torque, HP is produced.
What I meant (putting motor losses aside) when I said a electric motor is
always in it's peak power, was that if you dump 150 kW, or 200 HP into it,
you get 200 HP out regardless of speed, etc. When was the last time you saw
a gasoline engine start of at 0 RPM, and produce full HP until it's red
line? A general performance gasoline engine has a high power range in the
2500 to 5500 RPM range. It therefore needs to keep shifting into new gears
that bring the RPM's down, and thus the torque at the wheels. An electric
motor can produce full power (or close to it in reality) from 0 to 10,000's
of RPM's That is the difference with an electric motor and how a smaller
electric motor can beat a larger gas motor.
Because of this torque relationship, large diesel trains are not
mechanically powered! Large electric motors turn the wheels and a generator
is on the output of the engine!
>
>
> > The reason is the electric motor produces a high, continuous torque
over
> > most of it's power range. A gasoline engine produces a high amount of
> torque
> > over a small RPM range, and when you switch gears it produces a fraction
> of
> > the torque to the wheels. Torque is what moves a vehicle, and is related
> to
> > F=MA, where F = force, from the tires converting the torque to force, M
=
> > mass of the vehicle, and A = acceleration.. Solving for A = F/M, so
> clearly
> > increasing the torque will increase the force, and thus the
acceleration.
>
> ????????
>
> Torque: Something which produces or tends to produce rotation or torsion
and
> whos effectiveness is measured by the product of the force and the
> perpendicular distance from the line of action of the force to the axis of
> rotation.
>
Yes, I'm well aware of the definition. See above, maybe I straightened it
out a little. Don't forget the wheels turn the torque into linear force.
> > http://www.acpropulsion.com/PDF%20files/Living%20with%20an%20EV.pdf -
see
> > section 2.4, as it has a nice torque curve of a electric, vs gas. (BTW,
> if
> > the car had 200 hp of power on take off, that sloped line would continue
> up
> > to the y axis of the graph, so it's not using the full 200 hp until some
> > time down the road)
Did I mention that it's HP limited due to traction problems?
>
> ??????
> Are you talking about that messed up "tractive effort per vehicle weight"
> graph?
> What the hell is that?
The force that accelerates the car. Force is what matters in acceleration,
since A = F/M (rearranged F = MA). The torque is transformed into force
from the wheels. Smaller wheels = more force (at the expense of higher wheel
speed as the car speeds up). The distance from the bottom of the graph to a
line is proportional to the vehicle's acceleration.The electric motor is
accelerating at a constant rate when the traction control is on. When the
traction control is no longer needed, the electric motor is in a constant
power mode. With heavy, continuous acceleration, the total acceleration is
very high after several seconds. With the gas motor, acceleration starts off
slow, has a nice peak in the "power range" of the electric motor, then needs
to shift, greatly limiting the available torque at the wheels, and thus
greatly limiting acceleration.
>
> "A gasoline engine produces a high amount of torque over a small rpm
> range"???
>
> Here are some _real_ engine dynographs
> http://www.v8sho.com/SHO/dynographs.html
> (I used to own a gen III V8SHO, what a fun car to drive!)
Sweet! I always wanted something with a TPI 350 in it, now I want something
with a LT1 or LT4. With the performance of that Tzero, I may want to go with
electric soon!
>
> You can derive torque from HP and rpm, right?
Yes, and you can then turn the torque into force, if the drive train
reduction is known along with the wheel size. Wheel RPM, wheel size and HP,
or HP and speed would also work. Acceleration can be calculated from that if
the weight of the vehicle is given. Interesting they recorded the peak HP
much higher then the real peak. The HP peak does not count where the
transmission shifts and causes the stored up energy in the flywheel (shown
in the big dips) to be dumped all at once into the drive train, and thus the
spike.The net hp betwen the dip and spike is about equivalent to a
horizontal line, if that. The real peak is almost 50 HP lower then the
recorded peak HP because of this on the red line, first graph. I'm not sure
what those little spikes are from, perhaps a resonance in the air flow?
>
> <snip>
>
> K. Jones
>
>
Steve Spence
full size station wagon, a full size wagon won't get 87Wh per km. Users
won't accept a 31km range either. The batteries would not live long with
100% discharge either. Like I said, a trickle charger. PV is not a mobile
technology, period.
--
Steve Spence
Renewable energy and sustainable living
http://www.green-trust.org
Donate $30 or more to Green Trust, and receive
a copy of Joshua Tickell's "From the Fryer to
the Fuel Tank", the premier documentary of
biodiesel and vegetable oil powered diesels.
"Jeff" <levy...@hotmail.com> wrote in message
news:7ghAb.5763$IF6.2...@ursa-nb00s0.nbnet.nb.ca...
Steve Spence
Unacceptable. A biofueled hybrid electric with a pv trickle charger is a
good goal, but not a pv powered ev. I stand by my claim, pv on cars are no
more than trickle chargers.
--
Steve Spence
Renewable energy and sustainable living
http://www.green-trust.org
Donate $30 or more to Green Trust, and receive
a copy of Joshua Tickell's "From the Fryer to
the Fuel Tank", the premier documentary of
biodiesel and vegetable oil powered diesels.
"Jeff" <levy...@hotmail.com> wrote in message
news:1rhAb.5764$IF6.2...@ursa-nb00s0.nbnet.nb.ca...