Sidney:

On the RAV4 EV: I see your point.

But you are wrong about efficiency.

Power plants have an efficiency of 40 %
http://www.teriin.org/opet/reports/tpp.pdf
The charge discharge efficiency of NiMH is 66 %
http://en.wikipedia.org/wiki/Nickel-metal_hydride_battery.
This comes to 26 % efficiency for charging the batteries in the Rav4 EV
needs.
And of course the power transmission efficiency and the payload
efficiency drop caused by the battery should also be factored in.

The best internal combustion engines is 43 %.
http://en.wikipedia.org/wiki/Internal_combustion_engine :
The prius engine is 20 to *37 %*:
http://www.transportation.anl.gov/pdfs/HV/2.pdf


But this is not the really interesting thing.

Electricity is cheaper: Not because it is more efficient but because the
fuel is cheaper.
$9 to $42 / short ton
http://www.eia.doe.gov/cneaf/coal/page/coalnews/coalmar.html
8000 btu per pound * 2000 = 16000000 btu =128 gallons of gasoline @
125000 per gallon.
$9 to 42 / 128 gallons = 7 to 30 cents per gallon of gas equivalent.
And that's why electricity is cheap.

While the Rav4 is inexpensive to run it seems to burn more fuel at the
power plant than if it was a hybrid !!!

What has the Prius done ?
It's increased the efficiency from 35 MPG to 50 MPG or 50 % by not
wasting what the motive force the gasoline engine has produced.

Some info on the Raf4 EV:

http://en.wikipedia.org/wiki/Toyota_RAV4_EV

*The RAV4 EV closely resembles the regular internal combustion engine
<http://en.wikipedia.org/wiki/Internal_combustion_engine> (ICE) version
- without a tailpipe - and has a governed top speed of 78 mph
<http://en.wikipedia.org/wiki/Mph> (~126 km/h
<http://en.wikipedia.org/wiki/Km/h>) with a range of 100 to 120 miles
(160 to 190 km). The 95 amp-hour NiMH battery pack
<http://en.wikipedia.org/wiki/Nickel_metal_hydride_battery> has a
capacity of 27 kWh <http://en.wikipedia.org/wiki/KWh>, charges
inductively <http://en.wikipedia.org/wiki/Inductive_charging> and has
proven to be surprisingly durable. Some RAV4 EVs have achieved over
150,000 miles (240,000 km) on the original battery pack. It was also one
of the few vehicles with a single speed automatic transmission
<http://en.wikipedia.org/wiki/Automatic_transmission> at that time*

*As of May 2006, charging an RAV4 EV from full-dead to full-charge, at a
rate of US$0.09 per kilowatt-hour, costs around $2.70. As of May 2008,
based on a gasoline price-per-gallon cost of US$3.80 and up. and the
non-EV 2003 RAV4 2-wheel-drive gasoline fuel efficiency of 27 mpg_-US
(8.7 L/100 km; 32 mpg_-imp ), the RAV4 EV costs approximately 25% as
much to fully charge, and makes mileage in the RAV4 EV the cost
equivalent to a 111.1 mpg_-US (2.117 L/100 km; 133.4 mpg_-imp ) small SUV.*

Larry


sidneybrooks wrote:
> Try again.
>
> "http://www.engr.colostate.edu/~allan/engines.html
>
> Ever since the invention of the internal combustion engine, scientists and
engineers have worked to increase its
> efficiency. As it stands now, the average internal combustion automobile
engine only converts roughly 20% of its energy into useful motivational power."
>
> The Toyota RAV4 Electric batteries weighed 768 and had a range of about 125
miles, reportedly now improved to 150. Where do you get 1100lb for a range of 50
miles.
>
> --- In toyota-prius@yahoogroups.com, "Lawrence D. Lopez" <lopez@...> wrote:
>
>> I worked all this out to give me a sense of things.
>>
>> 1 gallon of gasoline = 125000 btu = 36 KW hours
>> A gallon of gas in Concord NH costs $2.50
>> That will buy perhaps 25 KW hours of electricity at 10 cents a KW hour.
>> But the gasoline engine is not very efficient.
>> Say 33 % so of the energy of a gallon gasoline will produce 36/3 or 12
>> KW hours of motive force.
>> So at $2.50 a gallon the net equivalent motive power of a gasoline is 21
>> cents per KW hour.
>> At $1.25 it is on par with electricity.
>> At $5.00 it is much more expensive than electricity.
>>
>> Gen 2 battery is 200 volts x 6.5 ams or 1300 ampere hours of 1.3 KW hours
>> Only about half of this capacity is used to prolong battery life so only
>> .65 KW hours is available.
>> It store 6.5 cents of electricity or the motive force of about .054
>> gallons of gas or about 6 cents worth of gasoline.
>> That would be enough to power the car for 3.2 minutes assuming 50 MPH
>> and 50 MPG.
>> Or about 3.2 miles.
>>
>> To drive 50 miles you would need a 200 volt x 102 ampere hour battery.
>> This would weigh something like 1100 pounds.
>> So much easier to carry 7 pounds of gasoline.
>> But the gasoline engine also has weight.
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>>
>> Stan Sexton wrote:
>>
>>> As the DVD "Who KIlled the Electric Car" pointed out, about 80% of us
>>> drive 29 miles or less per day. Even something as simple as the EV-1
>>> would be more than adequate for a large majority of commuters. The few
>>> that need to go farther can just jump in their hybrid. Not
>>> complicated. If battery packs could be standardized, you could go
>>> farther by incorporating "battery exchange stations". We have the need
>>> and the ability to accomodate this need NOW. Actually, we have had the
>>> ability to have this kind of system for some years now. We just lack
>>> the will (and something about GM and Standard Oil NIMH Patents).
>>>
>
>
>
>




Lawrence D. Lopez wrote:
> I worked all this out to give me a sense of things.
>
> 1 gallon of gasoline = 125000 btu = 36 KW hours
> A gallon of gas in Concord NH costs $2.50
> That will buy perhaps 25 KW hours of electricity at 10 cents a KW hour.
> But the gasoline engine is not very efficient.
> Say 33 % so of the energy of a gallon gasoline will produce 36/3 or
> 12 KW hours of motive force.
> So at $2.50 a gallon the net equivalent motive power of a gasoline is
> 21 cents per KW hour.
> At $1.25 it is on par with electricity.
> At $5.00 it is much more expensive than electricity.
>
> Gen 2 battery is 200 volts x 6.5 ams or 1300 ampere hours of 1.3 KW hours
> Only about half of this capacity is used to prolong battery life so
> only .65 KW hours is available.
> It store 6.5 cents of electricity or the motive force of about .054
> gallons of gas or about 6 cents worth of gasoline.
> That would be enough to power the car for 3.2 minutes assuming 50 MPH
> and 50 MPG.
> Or about 3.2 miles.
>
> To drive 50 miles you would need a 200 volt x 102 ampere hour battery.
> This would weigh something like 1100 pounds.
> So much easier to carry 7 pounds of gasoline.
> But the gasoline engine also has weight.
>
>
>
>
>
>
>
>
>
>
>
> Stan Sexton wrote:
>> As the DVD "Who KIlled the Electric Car" pointed out, about 80% of us
>> drive 29 miles or less per day. Even something as simple as the EV-1
>> would be more than adequate for a large majority of commuters. The
>> few that need to go farther can just jump in their hybrid. Not
>> complicated. If battery packs could be standardized, you could go
>> farther by incorporating "battery exchange stations". We have the
>> need and the ability to accomodate this need NOW. Actually, we have
>> had the ability to have this kind of system for some years now. We
>> just lack the will (and something about GM and Standard Oil NIMH
>> Patents).
>
>