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Comment: Re:other stuff matters also? I claim it does (Score 1) 330

by amorsen (#49405977) Attached to: Inexpensive Electric Cars May Arrive Sooner Than You Think

When it is merely cold, like -20C, electric cars are great. You arrive to a preheated and defrosted car and there are no problems starting the engine. 3kW of heating is quite sufficient when it includes heated seats and heated steering wheel, and that takes 3 hours to use 10% of the capacity of a Tesla 85kWh car. At slightly higher temperatures you can get a lot of benefit from the heat pump instead.

Now, lots of electric cars do not have suitably designed heating systems or batteries to handle -20C reliably. This is true of some petrol cars as well.

Comment: Re:Missing the point. (Score 1) 330

by amorsen (#49405893) Attached to: Inexpensive Electric Cars May Arrive Sooner Than You Think

Series hybrids are a terrible idea. See the BMW i3. It has worse mileage than most comparable cars. Its speed on petrol is limited, and the fuel tank is too small to be useful.

An electric drivetrain costs in the region of 30% of the energy that the engine puts in. Stuff an 8-speed modern automatic in there instead, and you keep the engine at almost the ideal RPM at all times. That drive train will have close to zero loss. Or put an extra electric motor in (two in total) and you get a variable ratio gearbox almost for free -- the Prius solution. Again, close to zero loss when running purely on petrol. Once you have a decent drivetrain, you can afford to put a slightly larger engine in and actually reach highway speeds.

Comment: Re: What an Embarrassingly Vapid Article (Score 1) 477

I will be surprised if most people manage to spend $1k yearly on car service after the switch. Except possibly if you include fuel costs in that amount.

A 10-year-old car is often expensive to keep running if you drive it a lot, and if you do not drive a lot, autonomous cabs will be a very cheap option.

Comment: Re:What an Embarrassingly Vapid Article (Score 1) 477

Busses are more expensive per seat than cars. They are somewhat more fuel-efficient when full compared to cars, but the difference compared with a full car is rather small. The major reason why busses exist is that one person can drive 40+ people instead of 3.

Comment: Re:What an Embarrassingly Vapid Article (Score 1) 477

If I have to stay late how do I get home? If I can leave early why would I want to wait for anyone else? If I car pool I can't stop and shop on the way home. I can't decide to go to the movie, or library on the spur of the moment because I need to worry about what other people want to do.

Why would any of those be a problem with a shared autonomous car? That is the whole point, there will always be a car ready, arriving within the 10 minutes it would likely have taken to walk to your car anyway. Zero minutes if you schedule ahead.

"Thank heaven for startups; without them we'd never have any advances." -- Seymour Cray