"But until we have cheap, 1000-mile batteries, we still need range-extending fossil-fuel engines." Why do we need thousand-mile batteries? My car doesn't have a thousand-mile gas tank and that's not really a problem.
It's a "the compass doesn't point north!" "we're not trying to FIND north!" kind of change in thinking. If you divorce the gasoline engine from ever needing to actually drive the car, you can work on just making an efficient gasoline GENERATOR instead to keep your electric car going.
That gave me pause too. My tank takes me 550-600 km on the highway, so at first that seemed sort of a dumb goalpost.
With a little reflection I don't think it's entirely dumb, but I think it really needs to explain itself.
I don't go nearly 500km in a single trip normally, so I'd have a chance to recharge my car regularly... usually. But I'm driving out of town in two weeks, and it's more than 500km away - I have to refuel, and I really don't want to camp for two-to-four hours at a highway service station.
For that long trip, what I need isn't a 1000-mile tank (or battery) - what I need is relatively quick "refueling" (recharging), which is possibly the biggest strength of liquid and gas fuels. A 1000-mile tank (or battery) is a "rocket equation" type problem - the bigger the capacity, the heavier it is, regardless of how efficient it is. And the heavier it is, the less efficient your vehicle is.
That's one of the other big strengths of liquid and gas fuels - as you burn them up, your vehicle gets lighter and more efficient; electric cars are unfortunately just as heavy whether you're fully charged or on your last gasp.
That said, it doesn't need to be as fast as pumping gas. I'd happily settle for a 30m "fast charge" on the highway; it's an excuse to get lunch and go for a quick walk, or grab a short nap.
Recharging the batteries in a hurry is problematic. You can refuel a gas tank in minutes and gas stations are abundant. While Tesla Motors is toying with battery-swap stations, there is still the problem of locating a high speed charging (or battery swapping) station when you are driving far.
It's cool, but it's not exactly Toyota's original design. German companies have been building prototypes of a similar linear generator for some time. Here's a video of one example. These are based on a "free piston" design used in German subs in WWII.
I thought this under-body placement of a free piston linear gen set would be the perfect range extender when I got into electrics about 20 years ago.
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(no subject)
Date: 2014-07-03 03:48 pm (UTC)(no subject)
Date: 2014-07-03 05:49 pm (UTC)(no subject)
Date: 2014-07-03 06:35 pm (UTC)(no subject)
Date: 2014-07-03 06:39 pm (UTC)(no subject)
Date: 2014-07-03 09:03 pm (UTC)With a little reflection I don't think it's entirely dumb, but I think it really needs to explain itself.
I don't go nearly 500km in a single trip normally, so I'd have a chance to recharge my car regularly... usually. But I'm driving out of town in two weeks, and it's more than 500km away - I have to refuel, and I really don't want to camp for two-to-four hours at a highway service station.
For that long trip, what I need isn't a 1000-mile tank (or battery) - what I need is relatively quick "refueling" (recharging), which is possibly the biggest strength of liquid and gas fuels. A 1000-mile tank (or battery) is a "rocket equation" type problem - the bigger the capacity, the heavier it is, regardless of how efficient it is. And the heavier it is, the less efficient your vehicle is.
That's one of the other big strengths of liquid and gas fuels - as you burn them up, your vehicle gets lighter and more efficient; electric cars are unfortunately just as heavy whether you're fully charged or on your last gasp.
That said, it doesn't need to be as fast as pumping gas. I'd happily settle for a 30m "fast charge" on the highway; it's an excuse to get lunch and go for a quick walk, or grab a short nap.
(no subject)
Date: 2014-07-04 12:22 am (UTC)(no subject)
Date: 2014-07-04 01:13 am (UTC)(no subject)
Date: 2014-07-04 04:31 am (UTC)(no subject)
Date: 2014-07-04 05:37 pm (UTC)I thought this under-body placement of a free piston linear gen set would be the perfect range extender when I got into electrics about 20 years ago.