Solar in a bottle is the practical alternative for wind and sun poor states
Did you ever expect to find cutting-edge renewable energy technology in your grammar school lunch box? Right there, next to your PB&J and a slightly bruised apple most likely sat a thermos bottle of milk or soup. That bottle worked on the same basic principle as solar thermal technology, the most practical renewable energy source for regions without the right weather to support today’s marquee renewables – wind power and solar photovoltaic. Which would be much of the continental U.S.Unlike photovoltaic and wind systems, solar thermal systems can store energy for use at night or on cloudy, windless days. Photo thermal systems are like huge thermos bottles that use sunlight to super-heat highly concentrated salt solutions. Insulated “bottles” trap the heat. When the wind doesn’t blow or the sun doesn’t shine, the trapped heat can generate steam to produce electricity or heat water to warm homes and businesses. Spain is starting work on a large-scale solar thermal plant for its Seville province in 2010.
Regions like New England, the Mid Atlantic and the Pacific Northwest could go Spain one better by combining solar thermal, wind and photovoltaic in one super-renewable energy system. We here in New England get wind, but not the steady, predicable wind that makes the Great Plains states ideal for wind power. We get sun, but not enough for large-scale solar, like the Southwest. So here’s an idea for the renewable-poor states. Build wind turbine farms for when the wind blows. Build photovoltaic arrays for when the sun shines. But don’t hook them up directly to the grid, use them to generate and store heat in solar thermal systems to match energy production with energy demand. What do you think? Practical, or a crackpot idea?
Tell me more about the energy transfer from thermos bottle to electricity; how does the hot salt create steam, temperature and pressure of the steam, steam turbine or steam engine (think old steam locomotive).
From what I've read, the heat exchange process for a large-scale solar thermal plant is similar to that for a household solar thermal array, especially the newer ones where the solar collectors heat the water indirectly by piping hot water through an exchanger that circulates cold in and hot out. The plants use the molten salt mixture to conduct the heat instead of the water-antifreeze cocktail that household systems use. IEEE Spectrum did a nice article on the technical details, if you want to check it out here: http://spectrum.ieee.org/energy/environment/larges.... Thanks for reading!