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by maigret 1087 days ago
EVs are highly efficient so the driving conditions make a huge difference. ICEs have a constant base consumption that we have gotten used to. It's unsettling at first, but as your consumption goes high a lot in high speed, you can save huge quantities (much more than you expect) by driving slower. You will lose less time than you think driving slower. Last time I spent 30 min behind a fast bus and quickly doubled my reach, more than enough to arrive home safely even while driving faster again.

I think the idea of not taking an EV because in some edge case one might lose a few minutes (30m for charging most vehicles nowadays) extremely superficial and selfish in view of the huge disaster that is the climate crisis. Think about how your kids and grandkids will read such comments in 50 years.
2 comments
kccqzy 1087 days ago
Here's a quick derivation based on first principles in high school physics. The amount of work done against a constant opposing force (imagine air resistance) is distance times force. If we assume a constant speed, then there is no net force and no electric energy is converted to kinetic energy, then all the electric energy is for doing the work. Suppose you are driving the same distance but double the speed, that fixed opposing force (air resistance) will quadruple. So doubling your speed consumes four times as much energy but you arrive in only half the time.

This is of course a crude approximation but just drive slower if you have range anxiety.

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maigret 1085 days ago
Exact - thanks for completing my point.
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birdyrooster 1087 days ago
If only there was some way to transmit the power from the engine to different gear ratios for efficiency at different speeds. That would be the future.
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maigret 1085 days ago
Not sure if you are sarcastic... Gear ratios are needed by ICE because ICEs have a much smaller RPM range, and can't go down to 0 without stalling. There are some EVs that have gearboxes, the cost/benefit of that is still unclear.
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detaro 1087 days ago
If only gear ratios fixed air resistance. Then your comment would make sense.
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birdyrooster 1086 days ago
How is air resistance the issue here? We are talking about the powerband of the motor. These are two independent concerns that ought not to be conflated.
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