29 Jun If we don’t want to run out of water, we should look to the sun
If we don’t want to run out of water, we should look to the sun – winter of exceptionally meager snowfall has revived California’s water woes. Snowpack typically supplies the state with much of its water during the spring and summer, but this year, snow is in short supply, spurring Gov. Jerry Brown to instate permanent conservation measures. Thanks to climate change, the problem is only going to get worse, leaving officials worried about the future of water in the Golden State.
Huntington Beach, a seaside Southern California city, is taking the long view, investing in a new desalination plant that will turn seawater into clean, drinkable H20. While the plant’s supporters say it’s necessary to guard against worsening water shortages, critics say the plant is a waste of ratepayer money, urging officials to manage water more efficiently instead. As temperatures rise and droughts worsen, this conflict is likely to play out in more and more coastal cities.
Central to this fight is the fact that desalination plants require a tremendous amount of energy, making them extremely costly to run. If that energy comes from burning fossil fuels, it will only make climate change worse. The Department of Energy (DOE) is looking to avoid this problem by funding research aimed at dramatically reducing the cost of using solar power to get the salt out of seawater.
Most desalination plants, including the one under construction in Huntington Beach, run seawater through a membrane that filters out salt, a process known as reverse osmosis, that uses a lot of power, which makes it rather costly. Avi Shultz, acting program manager for the Solar Energy Technologies Office at the Department of Energy, explains that, while reverse osmosis is state of the art for desalination, “it’s still not your first choice for generating freshwater, because it is expensive,” Reverse osmosis produces freshwater at a cost of about $1.50 per cubic meter, “which is really a little bit too expensive for it to be widely used,” he says. In the United States, the cost of water averages a little more than $0.50 per cubic meter, though it varies from place to place.