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Don't Waste Our Water Energy by Staff BPA Journal, May 2005

How much water does it take to generate enough electricity for a 2,000 square-foot home during one hour on a winter evening when the family is preparing a meal, using its furnace, lights and hot water, and watching TV? The answer is 60,000 gallons -- enough to fill the home about waist deep. The question is relevant as the region approaches a sixth dry year in a row, and BPA and other utilities and organizations are urging energy efficiency.

BPA's Ron Denis, an electrical instructor, has put together some data to help people understand the impacts of saving electricity. Especially in a low water year such as this. The numbers are based on flow through a single Columbia River powerhouse with an average head (of 100 foot) and efficiency (80%) as at Bonneville Dam Lower Granite, Little Goose or Ice Harbor on the Lower Snake River (see Power from River Flow, parenthesis and strike replacement by bluefish).

Here are some other comparisons in water "costs" for use of electricity:

• A 100-watt porch light left on for eight hours would use more than 3,000 gallons of water.
• A 3,850-watt hot water tank, heating for 90 minutes uses 22,860 gallons.
• A 400-watt PC running for three hours would use 4,750 gallons.
• A 4,000-watt electric furnace, running for four hours would use 63,335 gallons of water.
• A 700-watt microwave running for four minutes uses 185 gallons.
• A 1,200-watt vacuum cleaner in 30 minutes would require 2,375 gallons of water for its electricity.

1 acre-foot is 325,851 gallons. See also Power from River Flow