In “Analysts debate value of output ratings for solar projects” (May 20), Herb Eckerlin ignores the facts that are inconvenient to his argument. No one who installs solar (and no regulator, and no utility) is under the illusion that a 5MW solar plant will generate 5MW of power continuously. NO energy source produces its maximum capacity at all times. ALL energy sources are quoted two ways: energy and capacity.
The difference between the energy actually produced and the capacity is called the capacity factor.
Yes, coal and gas and nuclear have capacity factors much higher than standalone solar. But they also have the disadvantage of causing climate change (coal, gas) and extremely hazardous waste (nuclear, coal). Adding storage to renewables helps to increase the capacity factor, and solar+storage is beating coal and gas on cost in some states, with solar and storage prices continuing to drop.
If we really aren’t worried about avoiding catastrophic climate impacts, and if we really don’t care how much low-income people have to pay to keep the lights on, then go ahead and trash solar energy. But I worry and I care, and I’m not alone.
Sally Robertson
Chapel Hill