One advantage of using water to generate electricity is its low cost. Hydroelectricity is cheaper than electricity produced in coal-fired and nuclear power plants. This is because the fuel – water from rivers and lakes – is free. Water, unlike coal and uranium, is also a renewable resource. And since the fuel does not need to be burned, producing electricity from hydropower does not produce emissions.

Another advantage of hydropower is that the potential energy in water can be stored until it is needed to produce electricity. Then, it can be quickly converted to kinetic energy by allowing the water to flow into the turbines. The turbines spin, and the generators produce electricity in minutes.

Quick start-up times make hydroelectric plants ideally suited to provide peaking power. Hydroelectric plants can provide electricity in seconds at times when customers need it most.

In addition to ensuring a reliable supply of hydroelectricity for our customers, the lakes created by our hydroelectric plants provide communities with recreational opportunities, such as boating, fishing and swimming. The lakes also sustain wildlife habitats and offer water sources for everyday use to local communities.

At Duke Energy, we work in partnership with regulatory agencies, local communities and environmental organizations to protect and conserve environmentally sensitive areas around our lakes and to ensure an adequate stream flow to balance these many interests.

One disadvantage to hydroelectric power is that it necessitates the building of dams. While the reservoirs dams create can provide numerous recreational opportunities (e.g., boating, water skiing, and fishing), their creation floods large areas of land, eliminating wildlife habitats.

Additionally, while operating costs for hydroelectric plants are relatively low, the initial building costs are very high. Building large dams is both costly and difficult, making new hydroelectric plants an unattractive option for electric companies. Also, most suitable sites for hydroelectric generation have already been developed. In fact, the Catawba River, located in Duke Energy’s service area in the Carolinas, is one of the most electrified rivers in the world.

Over a century ago, the founders of our company had a vision: Let the powerful, 225-mile Catawba River energize a thriving Piedmont Carolinas. In 1899, Dr. Gil Wylie received permission to build and operate a hydroelectric plant at India Hook Shoals near Fort Mill, S.C. In 1904, the rope-driven waterwheels of the “Old Catawba” Hydroelectric Station turned generators for the first time, electrifying the grist and textile mills along the Catawba River Valley.

Soon afterward, tobacco magnate James Buchanan “Buck” Duke provided Wylie the capital for what later would become Duke Power. Great Falls Hydro, the company’s oldest operating hydroelectric station, started operation a few years later in 1907. A newer Catawba Hydroelectric Station replaced the “Old Catawba” plant in 1925. In 1960, both the station and the lake it impounded were renamed in honor of Dr. Wylie.

Today, hydroelectric plants are used mainly as peaking plants. These plants are designed to run for short periods of time when customer demand for electricity is high. When customers need power, Duke Energy’s hydro plants can be started up and begin generating electricity in only a matter of minutes.

Although hydroelectric generation makes up a small percentage of Duke Energy’s total generation mix, it is a critical part of our diverse generation mix.