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by blisterpeanuts 2136 days ago
>> Still orders of magnitude less energy-dense than jet fuel.

Does that matter, if other aspects of the system compensate with lighter weight? For example, lighter weight electric engines versus heavier fuel-burning engines along with exhaust and cooling systems.

2 comments

A PW150 turboshaft engine is ~5 kW/kg. Some electric motors are up to ~10 kW/kg. But, as an example, engines on a Q400 regional airliner are only ~5% of the total weight. Fuel is up to 15% of total weight. So the savings are not significant.

Also, the batteries will likely require a cooling solution. This can be challenging (heavy) for high altitudes (where air is cold but very low density). Jet fuel requires no cooling.

https://en.wikipedia.org/wiki/Power-to-weight_ratio

If it's anything like ships/yachts then the lighter weight doesn't come anywhere close to making up for the loss of energy.

Could still be very useful for flights between nearby cities e.g. LAX to SF.