That's right, they don't just have an upstream connection to the grid. they also siphon off some just to run. How much? Hard to say, as no company wants to publish figures-quite understandably! They are already woefully inefficient, artfully unreliable, ridiculously expensive, unhealthy for neighbors, harmful to local flying creatures, wasteful with some of the most scenic land. To say they sometimes COST energy from other sources would be political or financial suicide!