As the need for renewable energy increases options on energy storage have needed tactics on expansion to better meet the future needs of society. Consequently, wind and solar have not being able to compete with conventional energy sources such as coal, oil, and nuclear with out government subsidies because of the variability and the costly backup plants that supply energy when wind and solar is not available. Current methods of parabolic solar concentration use oil as a working fluid due to hold heat as the sun’s rays are focused on the pipes and pass the oil through a heat exchanger, thus making steam to turn a turbine to generate electricity.
Alternative storage methods being developed are such as enhancements to the existing lithium ion battery attached to a storage system or smart grid. Fairbanks, Alaska installed a football field sized nickel-cadmium battery six years as a solution to their energy isolation. While this is a step to battery storage system the questions still stand can a lithium battery be cost effect at the size needed to store energy from wind and solar farms.
In Iowa, Minnesota additional progress is being made to use excess electricity generated from wind and solar farms to pump compressed air energy storage into geological vaults and underground tanks. The 268-megawatt system releases the air as it powers a turbine that runs with 40% less gas than it would otherwise. This technology can reduce the amount of fuel consumed by as much as 70 percent. Developments in compressed air systems could potentially remove the need for gas in the process making it a completely sustainable technology.
PyroStorage has developed a new technology for mass amounts of successful sustainable energy storage by using raidio-frequency heating heavy oil deposits thus production liquid fuels without CO2 emissions. The PyroStorage technique uses a blend of oil storage capabilities synthesized with the characteristics of a microwave oven.
This process converts resources to a fuel for refineries with “5 times the electric energy input, the method provides a market for wind and solar power to meet a proposed goal of 20% of electric generation, while eliminating a source of CO2 emissions from fuels production.” This comparison to the present contribution of 2% that wind and solar power presently total toward the electric production is pretty impressive.
Refrances
http://www.green-energy-news.com/arch/nrgs2011/20110029.html
http://e360.yale.edu/content/feature.msp?id=2170
