Making Hydroelectric Turbines

For people who never outgrew the fun of playing with flowing water, making small hydroelectric turbines is a passion.
April/May 1994
http://www.motherearthnews.com/renewable-energy/hydroelectric-turbines-zmaz94amzraw.aspx
The principle behind all small-scale hydroelectric turbines is simple: a jet of water spins a blade wheel, which generates electricity.


ILLUSTRATION: FOTOLIA/MORPHART

Seventeen years ago, Dan New's father started making hydroelectric turbines near Deming, Washington. "He was just fascinated with falling water," says New. "I never understood it, until the day he let me turn on the penstock valve. When the lights came on, I was instantly hooked."

"I see water pouring out of a storm sewer, and I immediately start calculating head and volume," says New. "I can't help it.'

The hydro turbines he makes are at once simple and sophisticated. A metal shroud surrounds a wheel. The shroud is pierced by a nozzle. The nozzle emits a jet of pressurized water. Moving at up to 100 miles an hour, it strikes the wheel. The wheel is a turbine's heart. Spinning, it pumps electrons.

The wheels are surprisingly small and surprisingly beautiful. In this market, a nine-inch wheel is a giant. Harris' Pelton is just six inches across. Cast of bronze, its complex geometry is a work of art, a hydrodynamic sculpture. "What's elegant is the electricity:" New retorts. "You and I, we take power for granted, think it comes from an outlet on the wall."

"Energy is eternal delight," wrote the poet William Blake two hundred years ago. Throughout history, a good hydro spot was coveted and many a town was founded at a mill site. In 1880 there were 23,000 waterwheels between Maine and Georgia, and hydro supplied much of this nation's energy. By the turn of the century, 27 independent laboratories tested turbine designs.

"The shape of a Pelton wheel was perfected 70 years ago," says New. "In those days, before NASA, biotech, computers, nuclear physics, half the nation's brains were working on it."

During the Depression, small hydro was eclipsed by mega-dams such as Hoover and Grand Coulee. Cheap, subsidized power from the Rural Electrification Administration was the industry's death blow.

Today, however, it is enjoying a quiet revival. The current hotbeds are the Rockies, California, and British Columbia. The future, though, may lie overseas. Pakistan, Cuba, Peru, Laos—village power. There are 2 billion people out there with no electricity. If they all get it by burning coal ...well, let's hope global warming is a myth.

Already, New has installed systems in Morocco and New Guinea. His latest project was in the Aleutians. "I just love to unplug diesel generators," he says. Harris, meanwhile, is on his way to the highlands of Bolivia, where almost every village has an untapped stream.

So it goes with hydro enthusiasts. Motivated not so much by money as by the chance to continue playing in that ditch other boys forget when they grow up, they achieve a sort of immortality. Since a turbine's useful life is 50 years or more, wheels stamped HARRIS and NEW and CUNNINGHAM will still be spinning long after their makers are dead, transforming falling water into eternal delight.