On Sat, 21 Jun 2008 20:42:12 -0700 (PDT), Richard Riley
wrote in
:

On Jun 16, 7:37 pm, Larry Dighera wrote:
How Beat The High Cost Of Fuel

The motor is powered by a 78 pound, custom-built lithium-ion polymer
battery with a power output of "5.6 kilowatt hours"; projected life is
300 to 500 full discharge cycles or more than 1,000 partial cycles.
The battery can be recharged in as little as two hours using a
220-volt charger (or six hours with a 110-volt charger). The cost for
a full recharge is 70 cents with the 110-volt charger. Fishman says
it's feasible to carry a small 110-volt charger as baggage on
cross-country flights.

1 horsepower = .75kw. So 5.6 kilowatt hours is only 7.51 horsepower
hours. Good enough for a short burst to get you to altitude and soar
the thermals, bu you aren't going anywhere cross country.

I would say that depends on how much power the aircraft requires for
sustained level flight. If that can be achieved on 5 hp, the battery
will theoretically provide 1.5 hours run time (assuming 100%
efficiency).

Compare it to a really inefficient 2 stroke, burning .6 lb/hp-hr.
Your battery is equal to .75 gallons of gas.

What is the difference in cost between that amount of fuel and the
cost to charger the battery? Noise? Vibration? Reliability? ...

I give Mr. Fishman credit for the success his project has achieved to
date considering its funding and staff.