An unusual energy source gets a try-out
EARLIER this month engineers at Public Service of New Hampshire, the state's largest electric utility, successfully tested a novel fuel mixture for one of its electricity-generating boilers: coal tempered with cocoa-bean shells. Hedonists have long rhapsodised about the seductive power of chocolate; now cocoa power may light homes as well.
The 36,000 pounds (16,400kg) of bean shells used in the test came to the plant from Europe by way of Lindt USA, a subsidiary of Lindt & Sprungli in Switzerland, which operates a truffle-manufacturing plant in nearby Stratham. At the moment, the plant imports large blocks of chocolate from across the Atlantic to make into its "Lindor" truffles, but according to Peter Breed, the engineering manager at Stratham, the operation expects to begin processing its own cocoa beans into chocolate in the first quarter of 2010.
Hence the test. If all goes well, and if the test results are verified to the state government's satisfaction by a third-party auditor, which should happen within a few weeks, the plant will begin trucking mountains of used and otherwise useless (but free) cocoa-bean shells to the plant early next year. This, apparently, will be a first in America.
The shells, which have a thermal value similar to that of wood, will be mixed with the coal in a 1-to-33 ratio. An important part of the test was to see whether the power company's coal-grinding machinery could also grind cocoa-bean shells to the required talcum-like powdery fineness; the machinery performed admirably.
State officials, who had previously approved the utility's conversion of another boiler to burn wood, watched the testing procedure closely. Negotiating the necessary permits for the test took nearly two years, incredible though that might seem. Observers and neighbours, meanwhile, did a lot of sniffing. But to everyone's disappointment, coal and cocoa shells burned together do not fill the air with the sweet smell of chocolate.