Competitive costs give hydropower new spark

HOLTWOOD, Pa. -- The Holtwood Hydroelectric Dam on the Susquehanna River here hasn't changed much since it cranked up in 1910.

Outside, gulls perch on the crest of the dam wall above a picturesque waterfall as a lone boater skims across a serene lake.

Inside the long, narrow powerhouse lined with neoclassic arches and peeling green-and-white walls, 10 hulking, steel-encased generators emit a shrill hum. From below comes a steady, subway-train-like rumble — the cascade of water down the plant's sloping walls before it hurtles into turbines at 240,000 gallons per second.

Workhorses like the 109-megawatt Holtwood, which powers 90,000 homes in the region, have been criticized by environmentalists for the hazard they present to fish. They've been nearly forgotten amid the rush to trendier forms of renewable energy, such as wind and solar. But hydropower — the oldest and by far most widely used alternative energy — is quietly making a comeback spurred by a scramble for clean energy and the high costs of fossil fuels such as coal and natural gas.

Pennsylvania Power and Light is spending $350 million to build a sleek new powerhouse at Holtwood, the first new hydroelectric plant in the East in two decades. It will house just two sets of larger turbines and generators but boast a capacity of 125 megawatts, enough to light 100,000 homes, thanks to new, more efficient technology.

Old source of renewable energy

The addition is part of the nation's biggest hydropower expansion since the 1980s. Utilities are proposing more than 70 projects that would boost U.S. hydroelectric capacity by at least 11,000 megawatts, or 11%, over the next decade, according to MWH, a hydro engineering firm, and Hydro Review magazine.

"You're getting good, clean energy," says Linda Church Ciocci, head of the National Hydropower Association. "It's domestic, it's affordable, it's reliable."

In the early 1900s, hydropower was the dominant source of the country's electricity generation, a status solidified by massive federal projects such as Hoover Dam in the Southwest and Grand Coulee Dam in Washington state.