UTES - Renewable Energy Stores Beneath Our Feet

F. A. Michel - Director, Institute of Environmental Science, Carleton University, Ottawa, Canada. Concerns over energy dependence on dwindling hydrocarbon 'resources have focused attention on alternative renewable sources, such as solar, wind, biofuels, and hydrogen. Research on the technologies that will allow us to utilize these renewable energy sources economically has grown substantially over the past decade. Although largely ignored, the earth beneath our feet provides a myriad of options to consider, from direct utilization of high temperature geothermal energy, to the creation of hot and cold energy stores capable of permitting load shifting. Underground thermal energy storage (UTES) technology is versatile, flexible, economical, and can be adapted to account for local subsurface conditions. It is available everywhere, provided there is an adequate understanding of the local geology and hydrogeology. So what is it and why isn't it being used more widely?Ope