Posted: May 08, 2014
Balancing the renewable energy grid
The case for hydropowerMario Finis
Hydropower is currently the world’s largest renewable energy source, producing approximately 16 percent of the global electricity supply and nearly seven percent of the U.S. supply. Statewide, Colorado has the potential to add 3.8 gigawatts of hydropower, according to a recent report released by the Oak Ridge National Laboratory for the U.S. Department of Energy. For perspective, that’s enough power to light 2.85 million average American homes.
Policymakers and the environmental community are looking to hydropower to meet our nation’s energy and environmental challenges by maximizing the public benefit of existing water infrastructure. Last year a bill, co-sponsored by Colorado’s own U.S. Rep. Diana DeGette seeking to expedite licensing for developing hydropower on the nation’s non-powered dams unanimously passed signed into law. The bill was supported not only by the hydropower industry, but also American Rivers, the nation’s leading conservation organization, dedicated to protecting and restoring America's rivers.
As states increase their generation portfolio’s use of variable renewable technologies, like wind and solar, electric grids will need to rely more on firm baseload energy sources, like hydropower, to provide reliable electricity to consumers. As a clean, renewable and proven long-term energy source, hydropower deserves to be included in grid resource planning and to be part of our sustainable energy future for a changing world.
Hydropower has proven itself as one of the most reliable energy sources. Hydropower facilities can reliably dispatch power to the electric grid when needed as well as store energy by using technologies such as pumped storage which offer flexibility and very fast response to fluctuating power demands. During the 2003 Northeast blackout effecting nearly 50 million Americans, it was hydropower facilities operating nonstop that helped restore power to the impacted communities.
The tremendous power in our flowing rivers and streams can be predicted and scheduled for months of clean, reliable energy. This predictability allows hydropower to be used by electricity grid operators to provide the most efficient and cost effective mix of electricity to consumers.
Additional hydropower resources are available without building new dams or adversely impacting the environment. While some areas of the world may be suitable for responsible construction of new facilities, the U.S. has more than 50,000 non-powered dams with the potential to add over 12 GW of hydropower capacity by converting existing dams into electricity-generating facilities. This is enough to power more than 12 million average American homes, or nearly the amount of households in the entire state of California. By adding electricity generation to existing dams and water infrastructure projects, hydropower can provide renewable energy with virtually no additional environmental impact. Adding electricity generation at these facilities adds to the many other benefits these facilities already provide, such as navigation, flood control, water supply, environmental restoration, and recreation.
Hydropower partners well with other renewable energy resources. Hydropower can easily be integrated into the energy grid along with variable energy sources, like wind and solar, to provide stability and energy storage for clean power when needed. Because wind and solar power are used only when conditions allow them to produce energy, having a reliable source of hydropower available to backup these technologies allows even greater amounts of other renewables to be developed in a responsible and environmentally sustainable manner.
In addition, energy storage, in the form of hydropower pumped storage, is essential for grid reliability, providing one of the few large-scale, affordable means of storing electricity, making other resources more efficient and sustainable. Pumped storage projects store and generate energy by moving water between two reservoirs at different elevations. At times of low electricity demand, typically at night or on weekends, excess energy from sources such as wind, solar or nuclear can be used to pump water to an upper reservoir. During periods of high electricity demand or times when variable renewable resources are not available, water can be released downhill to generate electricity and maintain a reliable electric grid.
Hydropower is already the nation's largest renewable electricity resource and plays an integral role in our nation's diverse energy portfolio. Long project lifespans and zero fuel costs provide electricity at low costs to tens of millions of Americans from coast-to-coast.
With its proven reliability, availability and effective integration to support other renewable energy sources as they are brought onto the grid, hydropower is an important part of the overall renewable energy mix in keeping the lights on.
Mario Finis is senior vice president and director of hydropower and dams at Broomfield, Colo.-based engineering firm MWH Global, serves on the American Society of Civil Engineers Energy Division Executive Committee and the National Hydropower Association CEO Council, and is a member of the International Hydropower Association. Finis has more than 30 years of experience in the global energy and water resources industry and specializes in dam safety and hydropower. Reach him at Mario.firstname.lastname@example.org