Since its inception in the 1930s, pumped storage hydro has provided significant benefits to our energy supply system including storage, load balancing, frequency control and reserve generation. Pumped storage is now being applied to firm the variability of renewable power sources, such as wind and solar generation. Pumped storage absorbs load at times of high output and low demand, while providing additional peak capacity. With the advent of state by state Renewable Portfolio Standards driving the planning and commissioning of a tremendous amount of variable renewable energy projects across the country, America’s electrical energy infrastructure needs storage capacity more than ever. Pumped storage hydro is proving to be an enabling technology for these growing variable renewable power sources’ penetration into the United States energy supply system.

While the 31 GW of new pumped storage project proposals now before the Federal Energy Regulatory Commission demonstrates the hydropower industry’s commitment to building new pumped storage capacity to support variable renewable sources, developers still face significant obstacles, including an uncertain investment climate and long development timelines. Expanding the current investment and production tax credits, the possible creation of an energy storage credit, coupled with policies that recognize pumped storage as a part of the transmission system for purposes of qualifying for the transmission rate incentives currently afforded to transmission system upgrades and expansions, would encourage investment in pumped storage. This growth would displace the need for additional fossil-fuel based peaking generation, and provide the load management capacity necessary to meet our national renewable energy goals

This paper presents an overview and some of the key points of the 2009 Assessment of Waterpower Potential and Development Needs Report prepared by EPRI and can be found on their website www.epri.com. The assessment projects the amount of additional waterpower capacity that could be developed in the U.S. under conservative and aggressive scenarios. The middle ground or likely scenario is that with increased levels of research support and incentive programs, the U. S. can develop an additional 39,750 MW of waterpower capacity from existing conventional hydroelectric facilities and emerging waterpower technologies that access the energy potential of river, tidal, constructed waterway currents and the energy of ocean waves and thermal gradients.

Existing conventional hydropower generation represents 70 percent of the U.S. renewable energy generation (over 248,312 GWH) and the opportunity exists to expand this resource. The potential for waterpower expansion, at existing hydroelectric facilities, at dams without powerhouses, and from the emerging next generation of waterpower technologies, represents a substantial increase to the nation’s renewable domestic power supply. The 2007 estimate for waterpower that could be developed by 2025 exceeds the total wind capacity brought on line over the past 30 years (20,152 MW).

This paper reviews and ranks major proposed energy-related solutions to global warming, air pollution mortality, and energy security while considering impacts of the solutions on water supply, land use, wildlife, resource availability, reliability, thermal pollution, water pollution, nuclear proliferation, and under-nutrition.

To place electricity and liquid fuel options on an equal footing, twelve combination of energy sources and vehicle type were considered. The overall rankings of the combination (from highest to lowest) were (1) wind-powered battery-electric vehicles (BEVs), (2) wind-powered hydrogen fuel cell vehicles, (3) concentrated-solar powered-BEVs, (4) geothermal-powered-BEVs, (5) tidal-powered-BEVs, (6) solar photovoltaic-powered-BEVs, (7) wave-powered-BEVs, (8) hydroelectric-powered-BEVs, (9-tie) nuclear-powered-BEVs, (9-tie) coal-with-carbon-capture-powered-BEVs, (11) corn-E85 vehicles, and (12) cellulosic-E85 vehicles.