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Joined 3 years ago
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Cake day: July 3rd, 2023

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  • The point is, it’s not an apples to oranges comparison when you talk about the energy efficiency of an EV vs. a ICE car.

    Energy efficiency does matter because even if you are burning diesel to generate electricity, you can make power stations a lot more efficient than car engines. So shifting from ICE cars to EVs would reduce fuel use even in the absence of green electricity.

    ICE cars are inefficient, but carry around a very energy dense fuel source and can go hundreds, sometimes thousands of km without needing to stop. EVs have much more efficient engines, but have to drag around really heavy batteries that aren’t very energy dense.

    This is true, but like I said, the difference isn’t huge. An ICE car’s fuel + engine would be in the 100 - 400kg range, while an EV’s batteries + motor would be in the 200 - 500kg range. An additional 10% or so of weight is bad, but is outweighed by the at least fourfold increase in efficiency.

    60 kg of fuel, which can supply 2.74 GJ of energy

    ‘Contain’, not ‘can supply’ 2.74 GJ of energy. At 20% efficiency, you’d need a 800kg battery to match.