Improved Thermal Storage DevelopedCategory: Science & Technology
Posted: June 14, 2012 03:45PM
A problem shared by many power sources, including some environmentally friendly systems, is heat loss. Combustion is a very good way to release the chemical energy of a material but as much as half of that energy is lost as waste heat. Researchers have been constantly trying to find a way to use this heat and now many power plants actually use water tanks to capture and store the heat. Unfortunately the water will radiate the heat to the surrounding air, causing the heat to be lost anyway, and temperatures above the boiling point cannot be stored by the water. A new solution from Fraunhofer-Gesellschaft has been developed though, and it puts water to shame.
Zeolite is a material sometimes used as a water softener because of its highly porous nature. These pores are also what are needed for the material's thermal storage capability. Normally when steam encounters the pores it binds with the material in a physicochemical reaction that releases heat. Thanks to how thermodynamics work, this means that to remove the steam the system has to be fed energy, which it stores until it again binds with steam. In this case the energy being fed to the system is heat from the power plant.
A major difference between this heat storage system and the water-based method currently used is that this one has no loss. The energy is not stored by the zeolite pellets in a palpable way, so it cannot radiate out like the heat in water. The researchers are now working to improve their design by optimizing zeolite pellet size and coming up with a modular system so it can be built to any specific need.