But what about water power?

By Deborah D. Thornton


As the public policy battles over energy continue, is anyone investing in water energy? A recent report by the U.S. Department of Energy is increasing hydroelectric power’s visibility, especially in Iowa.

The prosperity of Iowa is closely linked to water, especially the Mississippi and Missouri rivers. Maybe it is time to capture this natural resource to make Iowans more prosperous.

Hydroelectric power is the production of power by using the gravitational force of falling water. It is one of the oldest and most widely used forms of clean, renewable energy in the world. In 2010, hydroelectric power provided over 3,400 terawatt-hours of power worldwide — about 16 percent of all the electricity generated. However, in the United States, only about 7 percent of our electricity is generated by hydropower.

The first modern water-powered electric plants in the United States were built in the 1880s in response to the high price of coal.

We have more than 80,000 dams in the United States, but only 2,500 produce electricity. The energy potential of the unused dams is simply wasted. The DOE report, “An Assessment of Energy Potential at Non-Powered Dams (NPDs) in the United States,” supports an expansion of hydropower energy in Iowa.

The DOE’s estimate of total potential U.S. hydropower capacity is 12 gigawatts. It takes one megawatt to power 400 homes for a year. A gigawatt equals 1,000 megawatts. Therefore, a gigawatt would provide electricity for about 400,000 homes per year, and 12 gigawatts would power about 4.8 million homes. Though actual production would be less, increases in hydropower could be a significant new, renewable addition to the energy industry.

Importantly, because the dams are already in place, much of the environmental impact and analysis, development cost and time investment has already been incurred. Adding power generation can potentially be done with lower cost, less risk, and in less time than building many other power sources.

Twelve of the top 100 U.S. dam sites are in Iowa, primarily Mississippi River Dams 9 to 18. The initial estimate is that these dams can produce electricity for about 236,000 homes. Hydropower plants on the two dams on the Des Moines River — Red Rock and Saylorville — have a potential capacity of another 90 megawatts, enough energy to power 36,000 homes.

It’s time for us to put the power of the river to work again.

Deborah D. Thornton is a research analyst with the Public Interest Institute, Mount Pleasant. The views expressed in this column are those of the author and not necessarily those of PII. Comments:

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