> when the wind blows, energy is basically free, and when it doesn't, it is extortionately expensive. This is why one must look at the whole spectrum not only

> when the wind blows, energy is basically free, and when it doesn't, it is extortionately expensive. This is why one must look at the whole spectrum not only on wind and solar. There is hydro, biomass[1] and geothermal as well. The latter is currently not so relevant directly for electricity in most regions, but has a hugh potential to replace other energy sources, including electricity, for heating buildings via heat pumps. [1] In the USA biomass plays a comparatively minor role in electricity production: 1.3% of all, 6.5% of renewables (half of solar). In a more advanced country like Germany the numbers are: 8.8% of all, 19% of renewables (a little less than solar). -- Sources: https://www.eia.gov/tools/faqs/faq.php?id=427 https://www.eia.gov/tools/faqs/faq.php?id=427 https://en.wikipedia.org/wiki/Renewable_energy_in_Germany https://en.wikipedia.org/wiki/Renewable_energy_in_Germany