07-06-2022, 01:33 PM
Power plants do not "dispose of" excess energy when supply exceeds demand. The smaller peaker plants ramp up and down as needed although every engine has a band of maximum efficiency and operating at low throttle setting is outside that band so is less efficient. The same is true for the large base load plants to a degree. They simply can't adjust output quickly enough, hence the need for small peaker plants.
Another issue is that in addition to being more efficient at high throttle, engines are also cleaner at full design load. You get more useful electricity for less fuel per kWh while producing less pollution per kWh if you don't have to throttle back and idle. This is very analogous to driving in stop and go traffic. These batteries will serve the same function as the batteries in a hybrid electric car. The fuel burning generators will still come on when required but will operate at peak efficiency and will shut off when they would otherwise have to operate inefficiently. In addition the batteries will also allow the integration of surges of renewable energy into the grid at the comparatively random intervals that are a fact of life for renewable energy. Rooftop solar probably produces as many kWh per day as the coal plant but does so in a curve starting and ending at zero as the sun is just rising and setting and peaking at noon, whereas the demand curve peaks peaks at sunrise and sunset and is lower in between. I don't know how much the coal plant actually ramped up and down but I know it would take hours to do so.
Another issue is that in addition to being more efficient at high throttle, engines are also cleaner at full design load. You get more useful electricity for less fuel per kWh while producing less pollution per kWh if you don't have to throttle back and idle. This is very analogous to driving in stop and go traffic. These batteries will serve the same function as the batteries in a hybrid electric car. The fuel burning generators will still come on when required but will operate at peak efficiency and will shut off when they would otherwise have to operate inefficiently. In addition the batteries will also allow the integration of surges of renewable energy into the grid at the comparatively random intervals that are a fact of life for renewable energy. Rooftop solar probably produces as many kWh per day as the coal plant but does so in a curve starting and ending at zero as the sun is just rising and setting and peaking at noon, whereas the demand curve peaks peaks at sunrise and sunset and is lower in between. I don't know how much the coal plant actually ramped up and down but I know it would take hours to do so.