I appreciate your honesty. There is presently no way of saying if this is a viable option for energy storage but I have to say that thermal storage has a number of limitations including the inability to store energy for an indefinite period of time. The goal shouldn't be to simply find a way to convert existing coal plants but rather to find the most efficient and cleanest means for producing and storing electricity.
Here is a company that was built on solar energy production and is now moving into the field of energy storage:
www.ise.fraunhofer.de
Their idea is not new but they are demonstrating the possibilities of using solar energy to create hydrogen. This makes sense in a number of ways:
- hydrogen is a clean burning fuel
- it can be stored until needed (indefinitely)
- it can be used by a number of different industries, as well as to provide energy to the grid (replacing natural gas, coal, diesel, etc.)
- ......
If you want to convert coal plants this is potentially the better way to do it.
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