Walking the Talk on Water
“Water is the new energy.”
So says my architect friend Rob Harrison, as quoted in the April issue of Metropolitan Home magazine. It’s a quip that may seem hyperbolic, or perhaps a little too cute. But not if you ask the United Nations. Expect to be hearing a lot more about “water footprint” in the not too distant future.
As CO2 emissions receive more and more of our attention, we must be careful not to neglect other critical resource issues, such as water. Indeed, in some cases CO2 emissions and water use are directly antagonistic. UNESCO-ITE recently found that biofuels are 70 – 100 times more water intensive to produce than are fossil fuels. In other words, biofuels may reduce your carbon footprint, but they also increase your water footprint.
Unfortunately, the semiconductor processing used to produce photovoltaic solar cells is also highly water intensive. I have not come across any analysis of this tradeoff, but if anyone out there has, please chime in.
Here in the Pacific Northwest, there is a particularly tangled web entwining energy use, CO2 emissions, and water. It has been recognized for many years that global warming will reduce snowpack in the Cascades, which will not only put the squeeze on Summer potable water supplies, but will also diminish flows through our hydroelectric dams, which, in turn, will force us to resort to using other, more CO2 intensive electricity sources, which will produce more global warming, etc, etc…