A New Era in Home-Owner Hydro

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To anyone familiar with electricity, that statement may sound absurd. After all, 400 watts is only enough power for four 100-watt lights—and a refrigerator momentarily draws 1,500 watts when its motor starts. But 400 watts, over 24 hours, is 9,600 watt-hours. And, believe it or not, that will amply fuel a modern version of what Zorba the Greek once jokingly referred to as the "complete catastrophe": husband, wife, kids, fridge, freezer, washing machine, dishwasher, microwave, computer, VCR, stereo, Dustbuster, Crockpot, plus a garage full of power tools. Note that these are standard, 110-volt tools and appliances—Makita, Kenmore, Maytag, whatever. You're not outfitting your house from an RV catalog.

There is, of course, a hitch. In most residential systems, you can't use an electric stove, electric hot water heater, or electric clothes dryer. They guzzle too much juice. No baseboard heat, either. For cooking, drying, and space heating, a hydro household will rely on sun, wood, and propane.

But wait. If a system only provides 400 watts at one time, what supplies the surges of power needed to start that refrigerator motor? For that matter, where does the power come from when 10 lights, stereo, washer, computer, and TV are all running in the evening?

Batteries. An inverter draws juice stored in a battery bank to start motors and meet evening and morning peak needs. The batteries recharge when the lights go off, or the next day when the kids are at school.

Thus, if you are willing to heat your food, home, and water with some combination of propane, wood, and sun, then a 300- to 500-watt system will provide all the electricity you need and then some. Nor is 300 watts the lower limit, particularly if you use energy-efficient lights and appliances. A 50-watt turbine, the Lil Otto manufactured by Bob-O Schulze, can power a weekend cabin, while 100-200 watts is adequate for an energy-conscious household. Don Harris, who built the Benzingers' machine, runs two houses and his shop (lathe, mill, etc.) on 150 watts of hydropower.

WHAT'S YOUR HEAD AND FLOW?
These two most important variables dictate how much hydropower can be produced.

What About the Cost?

If the owner of a PV system needs more power, they buy another module or two. In hydro, though, what you have is what you have. Moreover, the correlation between how much money a hydro system costs and how much power it generates is not linear. Sometimes it's inverse. A marginal site may cost more to develop, yet generate less power, than a prize winner. It all depends on stream size, penstock length, and other variables.

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