By MURRAY WALSH (Second in a four-part series.) According to this Our World in Data, earthlings used 173,340 terawatt-hours of energy in 2019. This is an average of just under 20 TWh per hour.   What does terawatt-hour mean? A terawatt-hour is a unit of energy equal to outputting one trillion watts for one hour. It is … Continue reading Murray Walsh: How to save the planet with energy, including fossil fuels