Originally Posted by Cobb
Its more like a day or so, but we dont know what the load will be on the engine and how it would effect fuel consumption. Seems the idle consumption is better than most generators from the start.
Yeah but that is comparing a car motor that is only putting out enough power to keep itself running to a generator that is producing its rated electrical output.
An ex-boss of mine had this saying, "A little science goes a long way." Along that line of thought, let's see how much fuel it would take to get 2 kWh of electricity using gasoline. Gasoline has ~33 kWh/Gal of energy,
Gasoline gallon equivalent - Wikipedia, the free encyclopedia
(Having worked out the answer beforehand.)
By pure chance 0.0625 gallons of fuel could produce (33 x 0.0625 =) 2.08 kWh if you extract all the power out of the fuel at 100% efficiency.
But the Insight gas engine, IMA and AC inverter aren't 100% efficient. As a WAG lets give the Insight gas engine 30% efficiency, the IMA 85% efficiency and the inverter 90% efficient. The combined efficiency would be .3 x .85 x .9 = 23%.
So instead of 0.0625 gallons/hr it would require 0.0625 / 0.23 = 0.272 gallons/hr.
Let's cross check that with just the efficiencies of the IMA and the new 2 kWh inverter using your idling fuel consumption, 0.19 / (.85 * .9) = 0.248 gallons/hr.
The above is close enough for government work.
The Honda EU20 2kW "digital" generator uses 0.169 gal (converting Liters/hr to gallons/hr) to output its rated 1.6 kWh.
EU20i Portable Honda Generator
Just for this example, if the Honda generator could continuously output 2 kWh and the fuel usage increased at the same rate, it might use (2.08 /1.6) * .169 = ~0.22 gallons/hr of fuel. That gives us an estimate that it is 0.0625 / 0.22 = 28% efficient.
All these numbers may vary.
 spelling mistakes
2005 Insight, MT, 88K, Silver
1988 Honda CRX HF, 44/51 mpg
1963 Lotus 7 replica, 12 mpg
1962 Henny Kilowatt, 40 miles/charge @ 40 mph