The following is not the same thing that Charlie is doing -- but Idaho Nat Labs has developed nano-antennas for rectifying IR heat - from solar.
http://www.sciencedaily.com/releases/2008/08/080810214010.htm In effect, a nanoantenna and a nanodiodes are not all that dissimilar. If either can be "printed" onto substrate, why not use both? IMHO it is not logical at this stage of technology - to try to cohere ambient heat anyway; when there is so very much medium-grade heat being wasted in exactly the same places where we need the electricity- to wit: automotive. Even without trying to get the big auto companies involved, 100 million automobiles worldwide are currently available - and awaiting any technology which can convert the exhaust heat to electricity, hopefully at about 15% efficiency. To be useful, of course, the drivetrain would also need modification, but it is easy to envisage a system of converting old autombiles to what is know as a "mild hybrid" and save lots of fuel as a stop-gap measure, untill something better comes along. http://en.wikipedia.org/wiki/Mild_hybrid This category of "mild hybrid" itself could even be enhanced by allowing the larger starter motor to actually run with the engine at low speeds, as GM has done with the Saturn Vue - to increase acceleration without the need of the large suge of fuel to increase torque. Even this can be taken to a step above what GM has done and for millions of cars out there as retrofit. The Wiki entry above mentions what the Chinese did for Taxis at the Olympics, and the is just a start. Almost as many kWs in heat can be dissipated by a redesigned catalytic converter than are available from the engine itself. Why struggle with ambient until this huge resource of waste heat has been exploited ? The Carnot efficiency of an ICE is higher, of course - since the peak temperature (the Carnot "spread) is higher than the exhaust. Still - squeezing 15% more energy by simply attaching a film of IR antennae or diodes or both - to a redesigned catalytic converter - makes lots of sense and could save an incredible amount of fuel and need not go through the burdensome channels of the automotive giants and the sticker shock of the final cost. I am anticipating that someone in a low-cost manufacturing economy - maybe the Chinese - will provide ** retrofit mild hybrid packages** which are easily adaptable to many high volume cars (Accord, Taurus etc - and especially pick-ups) which are already out there on road - hopefully soon. This product could have a two-year payback with gasoline near $4. Problem is - it would hurt the new car market. Jones
