Intermittent energy source: Difference between revisions

Revision as of 21:00, 14 November 2017

Revision as of 21:01, 14 November 2017

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===Complementary power sources and matching demand===

In the past electrical generation was mostly dispatchable and consumer demand led how much and when to dispatch power. The trend in adding intermittent sources such as wind, solar, and run-of-river hydro means the grid is beginning to be led by the intermittent supply from RES harvesting instead.{{Citation needed|reason=RES harvesting|date=November 2017))}} The use of intermittent sources relies on electric power grids that are carefully managed, for instance using highly dispatchable generation that is able to shut itself down whenever an intermittent source starts to generate power, and to successfully startup without warning when the intermittents stop generating.<ref>US Department of Energy: [https://www.energy.gov/sites/prod/files/2017/01/f34/Maintaining%20Reliability%20in%20the%20Modern%20Power%20System.pdf Maintaining Reliability in the Modern Power System], December 2016, p. 17</ref> Ideally the capacity of the intermittents would grow to be larger than consumer demand for periods of time, creating excess low price electricity to displace heating fuels or be converted to [[Energy storage|mechanical or chemical storage]] for later use.

The displaced dispatchable generation could be coal, natural gas, biomass, nuclear, geothermal or storage hydro. Rather than starting and starting and stopping nuclear or geothermal it is effective to use them as constant [[base load]] power, any power generated in excess of demand can displace heating fuels, be converted to storage or sold to another grid. Biofuels and conventional hydro can be saved for later when intermittents are not generating power. [[Fossil fuel phase-out|Alternatives to burning]] coal and natural gas which produce no [[greenhouse gas]]es may eventually make fossil fuels a [[stranded asset]] that is left in the ground. Highly integrated grids favor flexibility and performance over cost, resulting in more plant capacity and lower [[capacity factor]]s.<ref>Michael G. Richard: [https://www.treehugger.com/renewable-energy/death-capacity-factor-how-wind-solar-ultimately-win-game.html Death by 'capacity factor': Is this how wind and solar ultimately win the game?], 2015-10-06</ref>