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A comment on Rolls-Royce concludes testing of plane technology to break electric speed record. Parent comment

Re:Rolls-Royce concludes testing of plane technology to brea... by ashtonkem on Tuesday September 29, 2020 @05:30PM (#24633244)
Due to the way that power is delivered in an EV, the lack of a regular gearbox, and the non-linear nature of air resistance, EVs have ranges that increase the slower you go. At 20mph the range of a Tesla damn near doubles by some estimates. This is the opposite of how ICE cars work, which typically get better MPG at higher speeds due to gearbox design and variable efficiency based on engine RPM.

That’s probably why milk floats could go so far at the time despite obviously inferior battery technology; milk floats didn’t go very fast.

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Re:Rolls-Royce concludes testing of plane technology to brea... by Ari_Ugwu on Tuesday September 29, 2020 @05:39PM (#24633334)
To this point I wonder how full autonomy will impact this. A truck that drives itself and doesn't have to stop (besides to charge) will easily make the case for a freight or autonomous lane on highways where the vehicles don't go above a certain speed (67mph or 100kph). I don't really care if it takes me 10 hours to go 500 miles if I watch a movie, go to sleep, an wake up in front of my hotel.
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Re:Rolls-Royce concludes testing of plane technology to brea... by ashtonkem on Wednesday September 30, 2020 @01:38PM (#24641341)
Freight should be done more by rail. It’s way more efficient to ship by rail, and easier to electrify. Our heavy usage of semi trucks is partially due to the hidden subsidy that semi trucks get via road maintenance, where semi trucks don’t pay anywhere near enough gas tax to offset the damage they do. EV trucks will be worse.

Generally speaking, the solution for car troubles is to reduce the scope that cars and trucks are used to solve transit problems. Road damage due to semi trucks? Build more freight rail! Inner city congestion? Add a subway! Long commutes? Build more housing, and if that doesn’t work add dedicated commuter rails. Too much air traffic? Offset local flights onto high speed rail to free up room for long distance flights.

[ Parent | on HN ]