It takes a lot of water to make power.
Ohio’s coal-fired power plants, which produce nearly 90 percent of the state’s electricity, used 2.7 trillion gallons in 2010, mostly to help cool steam used to turn turbines and generate electricity.
How much water is that? Nearly 78 percent of the3.4 trillion gallons that Ohio households, farms, businesses and industry used that year.
That thirst, however, is on the wane. In 2000, for example, power plants used 3.2 trillion gallons.
Industry officials attribute that to the recession, which has reduced demand for electricity. Less electricity means less coal and less water is needed.
“It’s a direct correlation to how much power you produce,” said Mark Durbin, spokesman for Akron-based FirstEnergy.
Power companies will take even less water in years to come as more old coal-fired generators close in the face of tougher federal clean-air regulations. The biggest changes will come in 2015, when new limits on mercury and other toxic air pollutants take effect.
American Electric Power plans to retire its Picway plant, a generator at its Conesville Plant and four of its Muskingum River plant generators by June 2015.
And FirstEnergy says it will retire generators at four power plants along Lake Erie while Duke Energy will shut down its Beckjord station near New Richmond.
Together, these plants used 978.8 billion gallons of water in 2010.
Industry officials are quick to point out that most of the water that power plants draw in is returned to streams and lakes, but usually much warmer.
Melissa McHenry said that AEP has had to cut back generation at plants along the Muskingum River when stream levels were low in order to avoid overheating the stream and harming wildlife.
“It’s typically not a problem ever on the Ohio River,” McHenry said.