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Old 28th Jan 2020, 02:23
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Winemaker
 
Join Date: Dec 2017
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MCR01

I'm curious. 22 liters of petrol is about 16.5 kg providing about 45 MJ/kg, so about 740 MJ total energy. Assuming 25% efficiency of a piston engine, that's about 185 MJ of available energy. Lithium batteries (middle range) energy density is 0.6 MJ/kg. So, assuming 100% efficiency of the electric side, that means that to equal the energy of the petrol, one would need a battery pack weighting 185 kg. How could this possibly work? Have I made a maths error?
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