The Nuclear Notes - Will Small Modular Reactors Rescue the Grid from Solar?

https://www.linkedin.com/feed/update/urn:li:activity:7089592540483518465/ Will Small Modular Reactors Rescue the Grid from Solar? A well-recognized problem for power grids fed by a lot of solar panels is that when the sun goes down, they have to ramp up other power sources very quickly. And the time around sunset is usually a high-demand period, as people come home from work and turn on appliances. If we seek to decarbonize by switching to electric cars and electric heat, the challenge grows. Grid experts call the pattern of demand in a solar-heavy system the “duck curve,” because a graph showing the demand net of solar has a deep trough, while the morning and evening demand is high, creating a line that looks like the outline of a duck. The eastern United States does not have this problem, at least not yet. But a new study by the PJM Interconnection, the nation’s largest power market which extends from Pennsylvania, New Jersey, and Maryland (for which it was named) through parts of Virginia, West Virginia, Ohio and the Chicago area, predicts that the difference between the lowest level of demand, when the sun is shining strongly, and the level after sunset could be 70 gigawatts. Arshad Mansour, president of the Electric Power Research Institute, noted that this number is “more than peak summer loads in the Northwest and New England combined.” The first inclination of most system operators is to meet the challenge by cranking up gas turbine generators, which can respond quickly. Bu these emit carbon dioxide. To the extent that solar is paired with natural gas it limits the usefulness of solar in decarbonization. The problem is another illustration of why a “100 percent renewable” grid is an ideological position, not an engineering approach. Mansoor points to another possibility, that gas-fired systems will be started up during the day, to displace carbon-free renewables, to assure that the gas-powered generators are available at sunset. But, he notes, there are other ways to solve the problem, including changes in retail electricity prices, to give users an incentive not to use electricity at sunset, or adding transmission or energy storage. But small modular reactors could also help solve the problem, he argues. And when solar floods the market, the reactors can turn to other jobs, like making low-carbon fuels, he points out.