There is a growing awareness that there are two convergent crises facing the world: Energy and Water. Scientific Amercican just launced a dedicated environmental publication this month, Earth 3.0 and the cover story? … ‘Energy Vs Water’.
Electric hybrids are another solution to get away from imported gasoline. But if we switch to electric cars, we will need more electricity and at the moment 90 percent of electricity in the US is generated at thermal power plants, – those that consume coal, oil, natural gas or uranium, and these plants are water hogs. They use vast quantities of water for cooling. The US Army Corp of engineers is currently trying to find a middle ground in an interesting water drama unfolding between the states of Florida, Alabama and Georgia. Part of the problem is that both Georgia and Alabama have come dangerously close recently to having to shut down their nuclear power plants due to lack of water.
To help assess issues relating to water use and water balance, Professor John Anthony Allan from Kings College London, developed the concept of ‘Virtual Water’. He was awarded the Stockholm Water Prize this year for his work in this area. The idea is that you can calculate how much water there is in, say an apple, not just physically in the apple, but on a life cycle basis, how much water went into growing it, transporting it etc, By doing this with various food items or other commodities, a country could take a view to import ‘water heavy’ items, as a kind of a virtual way of importing water. For instance behind that morning cup of coffee, are 140 litres of water used to grow, produce, package and ship the beans. The ubiquitous hamburger needs an estimated 2,400 litres of water. Put simply, it may be more cost effective to import oranges from a region that has plenty of water than to try and de-salinate water at home to irrigate an orchard. Now that doesn’t always work though, you can’t grow things like oranges in wet damp countries like England.