surface at an average temperature of 14 °C. [5]  By  photosynthesis  green plants convert solar energy into  chemical energy , which produces food, wood and the  biomass  from which fossil fuels are derived. [6] Yearly Solar fluxes & Human Energy Consumption Solar 3,850,000  EJ [7] Wind 2,250 EJ [8] Biomass 3,000 EJ [9] Primary