The concept is that a decommissioned coal fire power plant has everything that a power plant or energy storage facility for a power grid needs except a source of power. So, if you can find a substitute for the coal fired power plant, the transition can be quite efficient.
The idea of using molten salt energy storage to fill part of the gap in employment and taxes left by the planned closure of the Routt County town’s coal-fired power plant is being planned by the unit’s operator, Xcel Energy, as it seeks to cut its greenhouse gas emissions.The technology was developed for use at concentrating solar power plants, where hundreds of mirrors trained the sun’s rays on a tower to heat the salt, which would later be used to power an electric turbine.“New players are looking at using the grid rather than the sun to heat the salt,” said Mark Mehos, a National Renewable Energy Laboratory researcher. “Then using the hot salt to make steam to turn a turbine.”While it may sound exotic, company executives, local officials and labor leaders say the initiatives being taken at Hayden could be a template for helping transition other coal plant-reliant communities.Coal-fired power plants are closing around Colorado and the United States – where coal-fired generation capacity has dropped by almost a third since 2008 to 223 gigawatts. In Colorado, by 2030 only one coal-fired facility, Xcel’s Comanche 3 unit in Pueblo, is slated to be in operation, as more than 30 units will have closed over 20 years.The state has created an Office of Just Transition to help power plant and mining communities faced with the end of the age of coal, appropriated $15 million to the effort, and developed a Just Transition Action Plan.
From the Colorado Sun.
Interesting,
ReplyDeleteGoes with the growing understanding that we need to overbuild both solar and wind above what is needed for the grid. Then dump the excess energy into some sort of storage. My bet for the winner is hydrogen generation at the point of use, i.e where the big gas turbines are. But this method could be in the running since the infrastructure already exists. When LCOE for solar gets down to a penny per kWh a lot of storage solutions become cost effective.
Cheers,
Guy
Good points.
ReplyDeleteI think there are too many fine details that matter to pick winners and losers yet though.
For example, the conventional separation of hydrogen and oxygen you do in junior high school chemistry class turns out to be quite inefficient. But with the right catalyst it can look a lot more attractive.
Another hydrogen option would be to extract hydrogen from coal in an air independent process that doesn't cause air pollution and then possibly oxidize it into something less tightly bound than water like hydrogen peroxide or ammonia, so it is easier to extract again.
Physically moving water between a water tower or higher elevation water tower, and a lower elevation reservoir could be easily arranged and work well in the foothills and mountains of Colorado, but probably wouldn't make sense in Kansas.
Battery technology has made incredible leaps and strides in recent years, and does scale well, and not all of it is dependent upon rare earths or other difficult to obtain materials (especially if you don't have to maximize energy density the way you do for a vehicle or a personal electronic device).
Even fly wheels and compressed air could be in the running.
Or, you could have high efficiency, room temperature superconducting lines that simply make long distance transmission on the grid so efficient that you don't need to store the electricity (either Norway or Denmark, I forget which, is now exporting electricity to the U.K. for the first time).
Ultimately though, in the long run (15 years plus), I think that nuclear power (probably fission at least at first) is going to win out to be the main baseline power source. And possibilities to make that more efficient, like co-generation plants that use waste heat for space heating and water heating, have the potential to make it a lot more efficient (as does fuel reprocessing).