Does fuel consumption depend completely on work done?

Question

I recently encountered a question in a physics workbook, a car of mass m kg is lifted by two cranes to a height of h metres, the cranes lift the car in t1 and t2 seconds respectively (t1<t2), then which crane will consume more fuel.....If we consider work as the main parameter then both cranes consume the same fuel (this is the answer given to the question), but surely work alone should not be able to determine the fuel consumption, a better parameter would be power right??

user215805 · Answer

Before jumping to your question

some assumption are required i.e both cranes should have same efficiency (in terms of chemical to mechanical energy conversion) otherwise a more efficient crane always consume less fuel for the same work
2 .Now back to your original question ,since mechanical energy require to lift the car is same in both cases (irrespective of what time it takes) and we get that mechanical energy from chemical energy of fuel  so for same amount of mechanical energy we require same amount of fuel if efficiency is same
3.Power determines how fast your work is being done ,so power gives idea about rate of conversion of chemical energy to mechanical energy or rate of fuel consumption rather than total fuel consumption

Does fuel consumption depend completely on work done?

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