Electricity Generating Jersey Barriers

http://www.ecogeek.org/content/view/524/

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Stand near a busy roadway and you'll be buffeted by gusts of wind as cars pass by. The majority of energy used in highway transportation goes to move huge volumes of air out of the way of our vehicles, not moving the vehicles themselves. So why not harness that energy and make it something useful?

That was the thought of Mark Oberholzer, who proposes installing small vertical-axis wind turbines inside 'Jersey barrier' highway dividers to drive electrical generation.

If you generate electricity from highway wind, then the highway wind is potentially slowed by the generator. When you have less highway wind, the cars might have to push harder against the air. If that were the case, they would waste more gasoline. No free lunch to be had here unless it is very well engineered to only take up the disruptive part of the turbulence that does not contribute to overall air flow -- properly designed there might be a trick that actually helps cars get better mileage but it is surely nowhere near as simple as just throwing vawts into jersey barriers. If you're going to re-engineer an entire highway system it might be more cost effective to ditch the idea of generating electricity from the wind and just find a way to ensure wind flows better along with the traffic. Given gas ICEs are horribly inefficient it's better to do source reduction than recovery.

IIRC someone else had this idea before and went so far as to test it, but found that it was more cost effective just to place the turbines in a well sited windy area than anywhere near the highway.

While no net energy increase is generated, the cost of producing power is shifted to another entity, the drivers, instead of being paid for by the power company. I wonder how much more gasoline gets wasted.. the energy sapped is distributed among thousands of cars. Does it cost the drivers only a few pennies extra per month? Could the energy produced and sold replace the revenue from toll booths on the NJ Turnpike?

Of course, even it it was only an incurred cost of a dollar or tow per month, you could expect a loud whine from conservatives, grumbling about how the government is "stealing" from them again, and that something is being "taken" from them.

::edited for spelling::

...mathematics-wise, as to what the effect would be. I don't know how much study has been done on highway air flow at all. It could be jersey barriers themselves either improve or ruin mileage, just by acting as a barrier between the two opposing air flows.