Heat engines lie at the heart of climate change

Your article (Spotlight, 23 July) notes that “something else is going on” with temperature records shattered in the north-west of America, Canada and Europe. More recently there have been severe rainstorms in Europe and China.

These climate change events are a consequence of the use of the heat engine, which generates power by the conversion of heat. A heat engine, deriving heat from fossil fuel combustion or a nuclear reactor, is a thermodynamically inefficient machine. The efficiency of the heat engine is generally less than 50%. Hence more than half the energy is immediately dissipated to the environment; ultimately, all the energy derived is dissipated as heat. This heat is over and above the heat that Earth receives from the sun.

Mankind should phase out the heat engine, and generate power using the radiant energy of the sun, directly with solar power cells and indirectly via wind and water turbines.

Prof David R Morris Fredericton,

New Brunswick, Canada