[wolfekeeper]

Obviously the initial investment would almost certainly be quite a lot higher for the self-builder, as old donor cars for a 'pusher' are cheap, whereas used gensets around ~10kW are not usually so.

About a grand from what I just looked up. They're standard bits of kit.

The pusher trailer on the other hand is a cheap and cheerful solution.

No, it's a complicated and difficult solution, you have to handle the gearing and control issues from the car in front. Both trailers and generators are standard items, that are easily available.

[CliffordK]

As far as a generator, the charging system in my pickup is about 6KW.
The drain is, say around 144V x 100A, or about 14KW.
A 6KW generator is relatively cheap, and would give me about a 30% duty cycle.  So, one couldn't just drive on the freeway all day, but one could drive longer distances with brief stops and layovers.
A larger generator would also have to have a redesigned charging system.

A "pusher" would be awkward to drive.  One would certainly have to carefully tie the engine and brake systems together.

I think the small pickups were frequently converted to electric as they already have good enough suspension to handle the extra weight of batteries. 

I have a classic VW Caddy that I've been considering converting.  About half the weight of the Ranger unloaded.

[peppercorn]

No, it's a complicated and difficult solution, you have to handle the gearing and control issues from the car in front. Both trailers and generators are standard items, that are easily available.

It's still cheaper for most cases, and remote throttle-control is not rocket science; though a four-on-the-floor gearbox may be more of a challenge admittedly!  Automatics have 'lock-up' speed I believe (never worked on one) so that might be a way around.

[crimsonknight3]

I'm not sure if someone has mentioned this yet but there is currently being developed a carbon 'slurry' that can store and discharge electricity at massive rates depending on the size of the slurry tank/converter, if this could be utilized for electric vehicles, they could run on a tank of said slurry, then when they need more power, go to a petrol station, attach the car and have the negatively charged slurry extracted and replaced with positively charged slurry?

http://www.sciencedaily.com/releases/2012/07/120711104809.htm

[Geezer]

I'm not sure if someone has mentioned this yet but there is currently being developed a carbon 'slurry' that can store and discharge electricity at massive rates depending on the size of the slurry tank/converter, if this could be utilized for electric vehicles, they could run on a tank of said slurry, then when they need more power, go to a petrol station, attach the car and have the negatively charged slurry extracted and replaced with positively charged slurry?

http://www.sciencedaily.com/releases/2012/07/120711104809.htm

Interesting article. Thanks for posting it!

If I understand this it's a sort of supercapacitor. I'd be a bit worried that the energy density will be insufficient. Currently, supercaps have only a fraction of the energy density of chemical batteries, and even they are barely adequate.

[CliffordK]

The carbon battery sounds interesting. 

Probably not in the near future for cars, but there is also work in liquid metal, or molten metal batteries for commercial applications.

http://www.technologyreview.com/article/412190/tr10-liquid-battery/
http://www.popsci.com/technology/article/2010-04/molten-metal-batteries-could-store-extra-juice-power-grid
http://www.upi.com/Science_News/2012/02/14/Liquid-molten-batteries-as-energy-aid/UPI-52301329262339/

Perhaps one could devise a liquid metal battery for very low melting point metals such as Mercury, Tin, Bismuth, and etc.

Actually, Sodium, Lithium, and Potassium might be interesting targets for a low temperature liquid metal battery.

[wolfekeeper]

I think the liquid metal stuff is much better for fixed applications.

[questioner]

The oil companies!

[wolfekeeper]

Not quite enough fast charging points, to properly cover the whole country, and not enough people with electric cars, so that people get to find out how good they are!

[crimsonknight3]

If I could afford one, I would definately own a Tesla.... Quite a few motorway service stations I have visited have specifically tesla charging points, if not then typcial generic electric car charging points... I'm never too far from a motor way it seems... From what I have seen recently though, electric car price has definately been coming down quite nicely, but reliablity and longevity still seem to be an issue, although with much thanks to elon musk it does appear that battery technology is improving vastly on 5-10 years ago

[alancalverd]

Convenience (or rather, lack of). I'm very impressed with the performance and capabilities of current Teslas but as work involves 200 - 300 miles per day I'd have to spend an extra hour each day (more in cold weather) waiting for the beast to recharge at a service station, and plan every trip via recharging points.  Arriving near-empty is not a viable option.

An electric bus, on the other hand, makes good sense, as would a better hybrid car, using an on-board gas turbine to recharge the battery on the move or whilst I'm actually at my destination. Problem with that, of course, is you can't use unreliable electricity directly, but it does at least guarantee that you burn the carbon or hydrogen fuel with optimum efficiency.