Stopping and Reversing Climate Change Part II

This article discusses quantitatively how to stop and reverse climate change. To stop climate change, we must transition from burning fossil fuels to using clean energy resources that do not involve the emission of CO2. We discuss the advantages and disadvantages of renewable energy sources, such as wind, water, and solar, relative to nuclear fission and the continued burning of fossil fuels, coupled to CO2 capture and sequestration of the flue gas. A plot of the energy per unit mass, epsilon, against the energy per unit volume, e, shows many orders of magnitude difference between changes in the mechanical state of ordinary matter versus chemical reactions versus nuclear transformations. These differences raise an apparent paradox concerning how the price of electricity can be roughly competitive for the commercial technologies based on the very different fuel types. Explicit and implicit subsidies for politically favored fuels give a partial explanation, but the turbines that turn flowing fluids into flowing electricity account for most of the result. Reversing climate change requires the world to extract CO2 from the atmosphere. Through the processes of growth and reproduction, evolution has endowed vegetation with the ability to convert carbon dioxide pulled from the atmosphere with water drawn from the soil into liquid and solid organic compounds. In the first part of the article, we recommended the carbonisation of the global annual waste from farms and ranches into an inert soil enhancer called biochar. We showed that burying biochar back into the soil of farms and ranches of the world suffices to lower the CO2 concentration in the atmosphere to a safe level by 2100 if some combination of renewables, nuclear power, and fossil fuel usage with carbon capture and sequestration can reduce to zero the emission of CO2 from total global energy consumption in 2050. In the second part of this article, we begin by describing how using hot molten salt to speed up traditional methods of carbonizing biomass can reduce the time scale for manufacturing biochar from days to minutes. The equipment needed to produce a tonne or more of biochar per day is compact enough to transport by truck to harvest sites. Because the biochar is not burned, but used to improve crop productivity and save water, this technology can meet the goals set in the first part of this article concerning the reversal of climate change if other technologies can transform the energy sector into a carbon-neutral activity. We then discuss how molten-salt breeder reactors can overcome the four usual objections raised by anti-nuclear groups to oppose nuclear fission: (1) sustainability of the fuel cycle, (2) superiority of the economics, (3) security against weapons proliferation, and (4) safety against accidental release of massive amounts of radioactivity into the environment.