Scientific American magazine’s February 2015 issue contained a very interesting article explaining the interaction of what may be the three most important problems confronting planners for the future of humanity. In particular, it stressed the urgent need for planners normally considering only one of the three issues to fully understand the relationship between the three as capital spending decisions are made. And to add to the puzzle, decisions involving the reduction of carbon emissions should also be informed by the continuum of energy-water-food system interactions. Unfortunately, decisions in the three areas are usually made by completely separate governmental or private entities, which makes intelligent decision-making (taking the interactions into account) extremely difficult. To add to the problem, many of the world’s population centers are hit with or facing drought, energy production is encountering increasing environmental restraints and the world’s food supply is straining to keep up with demand, with decreasing amounts of arable land available.
To frame the problem, consider California now suffering the worst drought in its history while still producing much of this country’s fruits and vegetables. The need for more water, the largest percentage of which is for farm use, is becoming almost desperate. California shut down two nuclear reactors in part for lack of cooling water. Still, environmentalists opposed the construction of a salt water desalination plant near San Diego (see my January 31st post) because the process is so energy intensive. And who will decide whether it makes sense for California to produce oil or gas via fracking (a water-intensive process unless exceptionally well managed) when other parts of the country (e.g. Pennsylvania, parts of Texas) have plenty of water.
Uruguay provides another good example of these interactions. The Uruguay River, which has a dam capable of generating as much electricity as the Hoover Dam was at very low levels in 2008. Eventually eleven of the fourteen turbines were shut down because of the need to store large quantities of water above the dam, as needed for farm irrigation and consumer use. Effectively, the citizens had to choose between food, water and electricity! Lake Mead may soon face a similar problem.
The article identifies some interesting choices, based on recent studies. As an example, intermittent wind power is more economically valuable when it is used to produce relatively clean water via (low energy-intensive) desalination of brackish water rather than producing electricity. This water can then be used to irrigate crops.
To look at another interaction, nuclear power plants and carbon capture installations at coal-based power plants are prime choices to avoid carbon dioxide emissions. However, both are very high water users. How to balanced the carbon problem against the growing shortage of water? These are the kind of tradeoffs that planners should take into account when new plants are being considered and where regional choices exist.
The article recommends funding research on energy technologies that are “water-lean”; water technologies that are “energy-lean”; and food production and storage that reduce energy and water use. Even without research, we already know how to make electricity distribution more efficient(e.g. smart grids) and how to reduce water use by eliminating leaks with wire sensors – allegedly 10-40 percent of flowing water is lost through leaks. Israel is a leader in this area – not surprising in a country short of water.