Energy on our planet is central to the functioning of our ecosystem and modern human society. This work attempts to put the various renewable and non-renewable energy sources at our disposition into context with extant and future human energy consumption. The 79,000 TWyr of solar energy hitting the earth’s surface annually constitutes the largest readily accessible energetic resource available on earth and the source from which most other (notably fossil) available energy sources are derived. Using the lens of reasonably assured recoverable reserves, we compare the percentage of this solar energy that can be converted to useable energy (electricity) to the potential of other renewable (wind, hydroelectric, geothermal, ocean thermal, waves, tides, biomass) and conventional reserves (coal, oil, gas, nuclear) and primary demand. We find that solar photovoltaics are capable of meeting 100% of extant global primary energy demand more than 12x over, wind 2x over even after reasonable constraints posed by land use and conversion efficiency. Under a fully electrified future scenario, solar power could meet global energy demand 27x over, and wind 5x over.
