Doesn a unit of electricity produced by wind turbines reduce a unit from another source?
Because the grid must continuously balance supply and demand, yes, it must reduce the supply from somewhere else when the wind rises enough to start generating power. If there is hydropower on the system, that is the most likely source to be reduced, because it can be switched on and off the most readily. Otherwise, the output from fuel-burning plant is ramped down or it is switched from generation to standby. In either case, it still burns fuel.
Because the grid must continuously balance supply and demand, yes, it must reduce the supply from somewhere else when the wind rises enough to start generating power. If there is hydropower on the system, that is the most likely source to be reduced, because it can be switched on and off the most readily. Some natural gas plants can also switch on and off quickly. Otherwise, the output from fuel-burning plants is ramped down or it is switched from generation to standby. In either case, it still burns fuel.
