The water situation in California is getting perennially severe. I have read several different stories and commentaries about possible solutions, and how popular or practical they are.
The most obvious solution is also the least politically possible. The state is along the shores of a limitless supply of ocean water. Yet the potential costs, in money and environmental impact, continues to hold it back. The most practical energy source for the desalination process would be atomic, but that carries too great an environmental stigma. Other energy sources have carbon problems, or other costly environmental impacts.
Another suggestion is “toilet to tap” — recycling sewage water for drinking water. Phrased that way it is unappealing, but for all practical purposes it is actually cleaner than what most people drink. Most sewage effluent is treated and then fed back into nearby rivers and streams, where cities draw their water into their water treatment plants. the “toilet to tap” water would go through more treatment than other effluent before getting blended with the rest of the tap water. Still, the solution isn’t very popular, despite the crisis.
And then I saw it in the movie Star Wars — the moisture vaporators — are the solution to California’s water problems. Pull the water straight out of the air.
Yes, I know, go ahead and laugh at a solution out of science fiction. Back in the 1980s they mocked the Star Wars missile defense system that way. The thing is, we are already using moisture vaporators — we just don’t recognize it!
Here in Missouri we have a dehumidifier for the basement. During the summer it generates around 5 gallons of water a day out of the air. We have a small room air conditioner for the upstairs dormer. It generates 5 gallons a day too. We haven’t figured out how to capture the water from the main heat pump in the house, but it obviously must generate more.
Our culture uses air conditioning, which rips moisture out of the air as it works, and all of it goes uncaptured. How much water could be gathered from homes, from stores, from offices, that goes wasted? The water is already being vaporated, it just needs to be collected. Politicians think big, but maybe people need to think small. Done properly, it won’t even use additional energy. How much more green could you get?
Alas, it is probably as out of date as the rain barrel, and so nothing will likely come of the idea.