[jgamman]

i used to work on the trading desk of an energy company that had hydro resources. the bid for hydro to clear the stack was always something like $0.10 ie, essentially free. Note: the clearing price was _always_ set by the last generating units offer price which tends to be coal/gas (here in NZ). If there was no clearing price, the offer price of hydro/solar/geothermal would go up to something like the Wighted Average Cost of Capital but there would competitive pressure from the other players to keep a lid on it. to a first order approx. in a _really_ complex industry/market it is absolutely OK to say installed wind/solar/hydro is free to run.