Bioenergy, Hydropower, Storage, Wind Power

Pumped Storage To Back Up Renewable Energy

Scott, I was informed by the lead engineer for the NY Power Authority that our hydropower systems like Niagara Falls operate at efficiencies over 95%. If this is true, wouldn’t it make sense to use wind powered electrical generation to pump water to elevated sources so the energy could be provided steadily from this source in times of low wind volume? — Tim G., Buffalo, NY

Tim, I couldn’t agree more that storage is the key for traditional energy and all renewables whether it be the intermittencey of wind, darkness for solar, drought for hydropower and biomass. Only geothermal and ocean energy (wave, tidal, ocean thermal and currents) appear immune. In my earlier Q&As, I addressed use of synthetic fluids, thermal salts and advanced batteries for storage as well as creating hydrogen as the storage medium.

Pumped storage is also a solid approach, assuming there either is an existing dam whose turbines can absorb the capacity or a man-made site where local environmental and site permitting allow diversions to conduit the water. Don’t assume, as professionals in the hydropower industry can add, that getting these allowances for a pumped storage project is easy. But with concerns about climate change and other emissions, I personally endorse pumped storage as far safer and more geographically dispersed than many other energy options being bandied about.  And especially for wind, where many times the resource doesn’t match the utility electric loads, pumped storage may be a viable option to add value to the wind or other renewable energy resource.

For further information:
1994 IEEE Study on reservoir size requirements

2005 Power and Technology Magazine article on required site indices for pumped storage