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Re: [EVDL] Converting from watt-hours/mi. to mi/gal & back

Engine tech usually uses a measure of "lb/hp-hr".
This is important because the energy in the fuel varies pretty much
consistent with its weight. While 1 gal ethanol, 1 gal diesel, and 1
gal gasoline yield very different mpg, 1 lb ethanol/diesel/gasoline
typically yield similar mpg in a piston engine unless some
rocket-scientist engine is being used. Carbon emissions are also very
consistent with mass, although this method of measurement predates any
serious interest in CO2 emissions.

0.5 lb/hp-hr is sort of "standard", though EFI makes it better but real
world driving conditions (esp idling where no miles are being produced)
makes it worse.

6 lb/gal of gasoline, .746 kwh/hp-hr= 9kwh/gal of gasoline.

The BEST 4-strokes yield around 0.4 lb/hp-hr, or 11.2 kwh/gal gasoline.

Actually I've seen performance numbers list 0.35 lb/hp-hr for
professional equipment run at its exact sweet spot.

Crappy 2-strokes, around 0.65 lb/hp-hr.

Danny

----- Original Message -----
From: Frank John <[email protected]>
Date: Sunday, September 9, 2007 11:21 am
Subject: Re: [EVDL] Converting from watt-hours/mi. to mi/gal & back
To: Electric Vehicle Discussion List <[email protected]>

> I read somewhere on the EPA or DOE website that fleet conversion
> efficiency is 16% but can't find the reference now. The only thing
> I could find is http://www.fueleconomy.gov/feg/atv.shtml
>
>
>
>
> ----- Original Message ----
> From: "[email protected]" <[email protected]>
> To: [email protected]
> Sent: Sunday, September 9, 2007 2:01:22 AM
> Subject: Re: [EVDL] Converting from watt-hours/mi. to mi/gal & back
>
>
> <...but an ICE will only get 20-25% of the total "to the road">
>
>
>
>
>
>
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