Want a plug-in car? Get in line - apparently they can't build 'em fast enough

Because you'd have a perpetual motion machine and violate the laws of physics.

Basically, a *lot* of energy is lost when you convert it from electrical (or in the case of gas engines, chemical) form to kinetic form (making the car move). It's a very inefficient process.

When you tried to switch it from kinetic energy to electrical again, you are also putting it through an inefficient process. It'd be like putting your dollar in a machine that gives you 50 cents back, and then putting your 50 cents into a machine that gives you 25 cents back.

You can get a little of the inefficiency back by using the heat generated by braking and other processes, and I *think* hybrids do that but I don't recall.

 

Some hybrids do use kinetic energy in that matter. What I'm talking about is this:

A car has four wheels, but all four are not doing the powering of the car. Some of those wheels are just along for the ride ... and, well, helping the car not fall over. So, then why couldn't those wheels not be hooked up to something that harnesses the fact that they turn. Think windmill.

A windmill generates energy because the wind turns it. Well, in a front wheel drive car, the rear wheels are doing nothing but rolling; they're not even turning (left/right) - wasted energy.

 

Yup. That's why hybrids have the counter-intuitive situation where they get better mileage in city driving than in highway driving.

 

Because those wheels moving *is* a form of kinetic energy.

The law of conservation of energy says that if you want to get some kind of energy out of that transaction, it is going to take away from the kinetic energy of the wheels. I.E. the wheels slow down.

In order to keep the wheels from slowing down, you'd have to add more energy to the transaction. And you'd be adding more than you get back because of the inefficiency of the process, otherwise you'd have a perpetual motion machine.

 

The wheels moving could be used to add to the overall battery charge, but they cannot be the only source of the charge.

There are multiple ways energy is being lost when a car is moving that will never be recaptured.

 

Not that I'm an expert, but enough time as a engineering major, albeit chemical, I do know that's not what would fall under the definition of a perpetual motion machine.

Think about it this way (and I know we're not this advanced with the batteries yet.) But you've got rechargeable batteries that you use for a camera or remote control or whatever. If it takes you 15 minutes to charge said batteries, but they last longer than 15 minutes.

You just have to be able to get what you're putting in to slow the rate of withdrawal thus extending the mileage you can get out of a car. Like a big-ass derivative.

One of our profs. told us this joke one day when some egghead said something defied something to which I can't even remember: A mathematician and engineer were put on one end of a football field and a beautiful woman on the other. The rules were laid out that every five minutes they could go half the distance between them and the woman. Once they reached her at the other end, they could have her.
The engineer takes off. The mathematician laughs and says, "It's impossible. You'll never get there. There will always be some distance between you two."
To which the engineer says, "True. But I'll get close enough for all practical purposes."

Right now, the practical purposes are 1. Extending the distance you can go on a charge. 2. Decrease the time it takes to fully charge a battery. The Volt goes somewhere around 50 miles on a overnight charge. That's not practical for an everyday car in the majority of the US. Flip that ratio from 50:8 to 50:2 and you're on to something.

The batteries will get better, and the cost of technology will go down, like it always does.

Heck, it could end up being a host of things working together to draw all available power sources. A roof that is a solar panel (costs too much now) that charges the battery, or a way to harness the wind so that it charges in short periods much like they've utilized braking's kinetic energy. Heck, even if we could use natural gas to power a generator that charges a second battery. When the first one runs down, it switches to the second.

This is one of Volvo's concept cars (It'll never be made) which uses nothing but air/wind.

That's the thing that most people ignore. They think battery, not batteries. Mainly because the cost of one of those things is so, so expensive.

It's just got to get to at least around 100 mile round-trip. That 25-mile crap might be alright in some places, but you'll never see one of those damn things around Atlanta.

Technology will advance. Prices will drop. It always does, especially when the consumer demands it. We think we have, but we haven't. The sales of SUVs alone shows that.

 

http://www.laautoshow.com/DC10/Volvo.html ... forgot to link the video. Never gonna happen, but it shows it can be done.

 

That looks like a car from Minority Report and it is also pretty freaking cool looking.

 

The Volt's also built heavier than it needed to be, which also restricts range.
The first-gen. EV1 had a range of 100 miles. Second-gen. had a range of 140. And that was more than a decade ago.

Also, GM leased 800 EV1s with an inflated sticker price of $34,000 and lease options of $399 to $549 monthly. They were also lease only. No purchase option up front or at the end of the lease.
Although GM priced the EV1 to fail, they leased 80 percent of the fleet.

 

This is the point at which I begin to realize that you are probably trolling me. I hope so, anyway, for your sake.

 

Yes, and technically the forward moving of the car is one of them, but since that's the point of the energy expenditure, it'd be kinda silly to try to capture it. This really is as simple as 1+1=2. If you take energy out of the kinetic motion of the wheels, the wheels will slow down.

There are other ways to make the battery more efficient that have been talked about, but using the kinetic energy of non-driving wheels is a non-starter.

 

The Volt also seats four instead of the EV1's two, and considering the additional engine for charging and the additional features and airbags and such (almost every car now is significantly heavier than 15 years ago) the weight difference isn't all that surprising. And considering it cost GM three times the sticker price to develop and build each EV1 I wouldn't call the price inflated or priced to fail. GM lost a crapton of money on the EV1, but learned a lot of the technological lessons that enabled it to do something like the Volt.