When I last wrote about this technique [AtE Oct 76], it was still in the laboratory, and the resulting material was still 100 times as expensive as the ordinary steel used for transformer cores. Today it costs only double. The leading manufacturer, Allied Signal Inc. of Morristown, NJ., has developed an alloy that radically reduces the area of the hysteresis loop (see figure), so that the total core losses (there are others) are reduced by 70%. A new 60,000 tons/year production facility is likely to bring down the cost of the material further.
Transformers using this material in their cores are produced by General Electric's plant in Hickory, N.C., and beginning in 1985, 1,000 such transformers were used by 90 utilities in a two-year field trial (25kW/single phase, often seen as gray cylindrical boxes on telephone poles or green boxes on concrete pads in shopping centers)
The transformers generally cost 25% more than those presently in use, but in transformers transmitting 10 kW or more, this is more than compensated by the energy savings over the life of the transformer. The two-year test showed the increased efficiency stable throughout the period and the transformers proved reliable (only 5 of the 1,000 had to be returned for repairs for such reasons as being struck by lightning). The three participants of the project, Allied Signal, General Electric, and the Electric Power Res. Inst. (EPRI) were honored last year by a professional group for "a major advance in the efficiency of electric power distribution sys-tems."
In late October, GE released the new transformers to the public market in ratings of 10 to 750 kW (actually kVA, but let's not worry about the difference here), and expects to have them available up to 2,500 kW over the next two years.
GE's claim, repeated by the Wall St. J., that replacement of the old transformers would reduce the need of new generating capacity by 8,000 MW or 8 nuclear plants, has a Lovinsian flavor and is mis-leading. Transformers of this kind have an expected life of 30 years, at best reducing the total need summed across the country by ¼ of a plant per year, and the need of any one utility by effectively nothing at all. This type of calculation assumes that everybody will junk his windscreen wiper as soon as a more efficient one is invented
¾with Lovins unsheathing his pocket calculator and proclaiming the energy savings sufficient to close down two GM production lines.This is not to belittle an important advance and a substantial energy saving. With the price mechanism in force, such admirable in-novations have plenty of incentive without coercive legislation by The Alliance to Conserve Energy and similar Konservation Komissars.
Now a footnote to the heat generated in large transformers. Apart from hysteresis, it is also due to eddy currents induced in the core and to normal resistance in the coils. This heat is dissipated via a cooling liquid and cooling fins. The liquid should be insulat-ing and incombustible like PCB. But on the most flimsy excuses, the EPA banned it as an alleged carcinogen that could reach people from waste dumps and forced utilities to return to mineral oil, thus causing not only enormous costs to the rate payer, but also a considerable number of fires [AtE Mar 85, Mar 86]. Now comes news that a bacterium decomposing PCB has been genetically engineered. If Jeremy Rifkin's inevitable suit against the bacterium is eventually rejected, and EPA's arsonists eventually again allow PCB to be used, the safety of transformer coolants will be back to where it was before the politicians, charlatans and publicity hounds began meddling
¾after the loss of uncounted lives, mil-lions of dollars, and decades of time.[More: "Transformers with lower losses," EPRI Journal (Box 10412, Palo Alto, CA 94303), Oct/Nov 1987, "GE research group develop highly efficient trans- former," Wall St, J. 8/25/88; reports and technical information sheets from GE Transformer Business Dept., Box 2188, Hickory, NC 28603.]
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Vol. 16, No. 4
Newsletter: Access to Energy Newsletter Archive Volume: Issues Issue/No.: Vol. 16, No. 4 Date: December 01, 2004 02:14 PM (For actual publication date see newsletter.) Title: Subsidizing science
Copyright © 2004 - Access to Energy Newsletter Archive
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