Invented is a method of making combustion air for a fossil fuel burner, as a coal burning power plant, oil refinery or gas fired household appliance. Combustion air is made from solar, wind, biomass, hydropower or geothermal. A staged progression using lower cost greenhouses, or flatplates, or solarponds, feed warm air to higher cost concentrator solar collectors. Wind energy, biomass, geothermal energy heat and compress combustion air. Hydropower also heats and compresses combustion air. Solar evaporation from salt or impure water creates water or local rain for the hydropower system. Combustion air thus is made economically hot, compressed and high velocity, and placed into a heavily insulated pipes for long distance transmission to a distant power plant.