Sunday, November 4, 2018

Thinking About Renewable Energy

Among conservative writers it is popular to denigrate wind and solar energy, as John Hinderaker of Power Line does here. The ususal rap is that both sources are intermittant and require fuel or nuclear-based backups, which is certainly true today.

The key issue is how to store power generated when the wind is blowing or the sun shining. Battery technology is improving but shows no signs of reaching true large-scale feasibility, perhaps ever. Other alternatives do exist.

In areas with mountains, one answer is hydropower, the power of water flowing downhill. We have examples in CA where water behind dams is released to generate power, and where - when excess solar power is generated - water is pumped back up into the dam, raising the lake level, so it can be used again to generate hydropower when solar generation stops.

Another way to ‘store’ solar and wind power is to use the electricity so generated to separate water (H₂O) into H and O - hydrogen and oxygen - via electrolysis. Stored H and O can later be recombined or “burned” to create heat with water vapor as the only residue or ‘ash.’ The steam so produced can create electricity via turbines.

I’m guessing technologically sophisticated folk can think of other ways to store solar/wind generated electrical energy until needed at times when the wind stops and the sun doesn’t shine. For example, ‘green’ energy could be used to create vast amounts of heat in a large insulated container of molten salt which could subsequently be tapped as a power source.

My personal favorite ‘clean’ energy source is hydropower, the power of falling water, stored in mountains by dams creating lakes for recreational use. We have them on the South Fork of the Feather River in CA and they have produced trouble-free clean power for generations.