3 ms·
How does change in energy density over time affect the viability of the energy source? Going by your numbers, jet fuel maintains 46MJ/kg as it is depleted—the
by abtinf 5y ago
How does change in energy density over time affect the viability of the energy source?
Going by your numbers, jet fuel maintains 46MJ/kg as it is depleted—the last kg has the same energy density as the first kg. I would exclude the weight of the enclosing tank because I think that’s usually the airframe itself.
Batteries start at 1MJ/kg for the first MJ and fall to 0MJ/kg when depleted (I don’t know what the curve looks like, but I’d expect it to be worse than linear).
What is the practical impact of this difference, if any?
- phreeza 5y agoIf energy is consumed uniformly over time, and all fuel is consumed during a flight, it would mean a factor of 2. Using a lot of fuel during takeoff would mean a slightly higher factor, but keeping a fuel reserve would decrease the factor, so it would probably come out even?