The marginal cost of hydro energy is nearly nothing. If you build a dam but the local city or factory no longer needs the energy, it costs you nothing to keep s

The marginal cost of hydro energy is nearly nothing. If you build a dam but the local city or factory no longer needs the energy, it costs you nothing to keep sending the water down the turbines. The coal plant might have been cheaper to build, but to produce electricity you need to keep on mining coal for it. An even better scenario is if the government subsidizes the building of the hydro plant - then you get cheaper up front cost and cheaper recurring costs. This is the case in Austria, according to HydroMiner[0]. [0]https://www.hydrominer.org/faq/ https://www.hydrominer.org/faq/