A Practical Way to Make Power From Wasted Heat By KENNETH CHANG
Scientists at M.I.T. and a small company in Salt Lake City are scheduled to announce today that they have developed technology that can efficiently (1a) and inexpensively transform heat pollution into electricity.
Although only a few crude samples have been built, Dr. Yan Kucherov, director of research and development at the Salt Lake City company, Eneco Inc., and Dr. Peter L. Hagelstein, professor of electrical engineering at M.I.T. and a technical consultant at Eneco, say that their devices improve the efficiency of the conversion by more than half.
"It's really first-generation, very primitive implementation," Dr. Hagelstein said. "Potentially (2), it's an enormous deal. This opens a door."
While the heat generated by car engines and power plants usually does nothing but warm the surrounding air, scientists have long dreamed of building so-called thermoelectric devices that can capture the wasted heat and convert a portion of it into electricity.
Such devices could significantly increase the electrical output of existing power plants or power the electrical systems of automobiles, replacing alternators and increasing gas mileage.
The Pentagon, which partly financed the new research, has been interested in using the devices for silent motors. Operating in reverse, thermoelectric devices can also be used as refrigerators (3).
Another advantage of thermoelectric devices is that they produce electricity without generating additional pollution.
Current thermoelectric technology converts only about 10 percent of the heat it absorbs into electricity, too inefficient (1b) a return for widespread use. The new devices, however, reach about 17 percent, and Dr. Hagelstein said future devices should be able to improve upon that significantly.
It is impossible to transform 100 percent of the heat into electricity. The laws of physics dictate a theoretical maximum of about 50 percent at the temperature a thermoelectric device operates at. Current commercial thermoelectric devices, at 10 percent efficiency, get only one-fifth the maximum. Using the new technology, future devices should be able (4) to achieve more than half the maximum.
The researchers are presenting their findings at a meeting of the Materials Research Society in Boston. Scientific papers describing the experiments have been submitted to the journals Physical Review Letters and Applied Physics Letters.
If borne out (5), the findings would be significant, said Dr. George S. Nolas, a professor of physics at the University of South Florida and an organizer of a symposium about thermoelectric devices at the Materials Research Society meeting. Dr. Nolas had not seen the Eneco paper but said the reported efficiency was high enough to find practical use and "would be pretty good news."
Eneco's thermoelectric device is a sandwich of three layers of semiconductor. One outer layer is heated; the other is kept at room temperature. The middle layer acts as an insulator to maintain the temperature difference.
The heat causes electrons to shoot out, some crossing the sandwich to generate an electrical current. The Eneco researchers added impurities – a process called doping – to the heated layer to increase the flow of electrons.
"The region near the hot part is heavily doped, so it boils off electrons," Dr. Hagelstein said. "We get more voltage and more current."
He added: "The underlying technology is really very simple (6). It should be a very practical, relatively cheap technology."
Leroy Becker, marketing director of Eneco, which is not associated with the Dutch utility Eneco Energie, said the company hoped to produce (7) a prototype of a practical device (8) within a year and sell it within two years.
Eneco, a privately held company, was created in 1991 to seek to license patents on cold fusion (9) after the controversial claim of two University of Utah scientists that they could produce almost limitless amounts of energy in a room-temperature flask of water. Eneco also financed follow-up research on cold fusion, including work by Dr. Hagelstein. The claims for cold fusion were far overstated (10), and several years ago, Eneco shifted its focus (11) to thermoelectric devices.
Let's suppose that the people who brought you "vibrating vacuums" and "protons older than the universe", actually came up with Device J-666 which would convert the lost heat energy of an automobile engine into electricity. Did they mention that these engines – internal COMBUSTION engines – are HEAT engines in the first place? So, if J-666 converts heat into electricity then there would be NO NEED for the piston engine at all and certainly NO NEED to use it as an auxiliary device. Fasten J-666 to an electric motor and top it with a saddle. Hi ho Silver – and away!
Another thought. Just how large will this J-666 machine be anyway? Will it need a few acres, like solar power, to move a tray of bagels across the room? Moreover, my cousin's old 1957 Corvette has a 270 HP engine. Why don't you check on how LARGE, and HEAVY, an electric motor must be to deliver such power. It's a good laugh.
For the curious, they might like to research the Sterling engine – an external combustion piston engine. Steam engines use externally produced gas (steam) pressure to drive pistons. The thrasher which powers my Titanium plated BMW (joke!) sets fire to gasoline within the cylinder to produce gas pressure which moves the piston.
Always keep in mind that our meta-scientists would be out of work if they didn't dream up things to do. "Research" is like a hydra – cut off one arm and two more grow in its place. I think it was Tufts University where millions were spent on grafting a human ear on the back of a rat. Personally, I'd like to see a rat's ass grafted on Greenspan's ear. It would improve his looks.
Moral: There is absolutely no logical reason for making anything more efficient as long as the several human species continue to reproduce unfettered. MORE only creates MORE of the problem the research daffies tell us they want to combat. Our problem is BIOLOGICAL and not whether some fart mobile is 83% or 97% efficient. To water your roses, instead of the house which is on fire, is one way to label insanity. The last relatively sane decade was the 1930's. However, in an asylum, all think they are sane. The gods have made us mad and Don Bush is leading the windmill charge while being advised by the Queen of Hearts.