2e; The ability to charge on the go?

[palmer_md]

Originally Posted by KarenRei

The problem is that EMF inductive coupling loses a lot of energy with distance. There are some resonant coupling schemes, but even they generally lose about half or so of their energy over ~8 feet. And they're pretty bulky for how much power they transmit.

Yeah and I was momentarily confused in my thought process when I thought this was "waste" energy. It isn't and that makes a big difference in the cost analsys. If it was waste, then they could charge 50% of a normal rate for a 60% efficient process and everybody thinks they are winning, but this is not true so does make the concept hard to swallow. But still fun and interesting none the less.

[KarenRei]

Yeah... it's a neat concept for some day, but it's not ready for prime time yet.

A couple decades to get EVs on the road in good numbers, plus a couple decades of wireless power transmission tech advancement, and people might start to look at it more closely.

[LTLFTcomposite]

Originally Posted by KarenRei

Yeah... it's a neat concept for some day, but it's not ready for prime time yet.

A couple decades to get EVs on the road in good numbers, plus a couple decades of wireless power transmission tech advancement, and people might start to look at it more closely.

How about a groove in the middle of the road with a metal strip running along each side. Each car could have a pin that rides in the groove and pickup shoes that contact the metal strips. Wonder why nobody ever though of that.

[LTLFTcomposite]

On a more serious note I think there could be value in a small genset, even if it isn't big enough to keep up with steady state load at 65mph. If it could supply, say 50%, you would a) double your range b) probably more than double range when you factor in longer stops like a meal or sustained periods of stop and go like a traffic jam, and c) push comes to shove if you're runnin' on em-tee you could always find a place to hang out and let the charge build back enough to get you home (without finding a charging station, which you can expect to be pretty much non-existant in the early days)

[gistmarrs]

I think there could be value in a small genset, even if it isn't big enough to keep up with steady state load at 65mph

I was arguing for this earlier in the thread. I had a hard time convincing anyone of it's value for some reason. I used Karen's state of charge calculator and entered in 2,000 watts of solar panels on the roof just to see what the effect would be on the driving distance, and was amazed. It really makes a huge difference if you aren't immediately on the freeway and doing 70mph for the whole trip. If you figure in a pit stop after 1 1/2 or two hours the distance really increases.

[PatQ562]

My personal opinion is that once one has introduced the noise and fumes of a "small" genset, for not much more money, and no greater noise, you could have an "adequate" genset that actually supports continuous driving. Of course if you want this to be clean and refined you need to go through the whole "hybrid" qualification process. But if you just want to stick something in, why stop halfway?

Again, personally, I'm more interested in a silent all-electric scheme, so I'm a bystander on the genset question.

Pat Q

[chijayhawker]

Resurrecting this thread with today's article. Oh if only it could become reality:
http://www.physorg.com/news/2012-02-...e-highway.html

[rayfellow]

The last I read of this, there was a great deal of power lost in the transfer.

[randyd]

I don't know exactly how they measured the efficiency. I am sure they did not include transmission losses getting the electricity from where it is generated to each sub-pavement coil, but they claim 97% efficiency thanks to sympathetic resonance between the transmit and receive coils.

To paraphrase Mark Twain, "There are lies, damned lies, and efficiency calculations."

[SEGsby]

I recall discussing this as part of a National Transportation Initiative across the US-- but it was "poo poo'd"' upon.