Over spring break, I did what university faculty members are notorious for. I attended an academic conference in Las Vegas — and got more depressed about the state of the world!
At the opening plenary session, the speakers talked about the increasing problems with water in the American Southwest, which might also be related to systematic changes in worldwide precipitation patterns. One piece of local data: Water levels in Lake Mead, the reservoir behind Hoover Dam on the Colorado River, are down to 48 percent of capacity.
So the following day I headed out to Hoover Dam — consistent with the teacher in me who favors field trips as key learning exercises. My previous visit there was more than 10 years ago, when my parents visited us from India. My father had studied about Hoover Dam in his civil engineering program, and I recalled his eager beaver excitement when we were there.
This time around, the low water level was obvious. The bathtub rings above the water’s surface looked like nasty scars. To see the conditions in person was way more real and worrisome than it was when I listened to the speakers while comfortably perched in the conference hall.
Tourists rushed past me as I was parked overlooking the dam, and I wondered how the changing water and drought conditions around the world might affect electricity generation. We tend to forget that even coal-fired power stations need a lot of water; globally, about 45 percent of electricity comes from coal.
I grew up in an industrial company town — Neyveli — in southern India, where the principal activity is to generate about 2,500 megawatts of electricity by firing up the lignite mined there. Lignite, a variety of coal, has a low energy content compared to more energy packed varieties like bituminous or anthracite.
Generating power from lignite requires water every step along the way — which, in Neyveli, came from underground. The area was fortunate to have extensive aquifers, naturally recharged by the approximately 40 inches of monsoon rains every year. However, many engineers, including my father, were and are worried that continued large-scale use of groundwater might catalyze sea water intrusion — after all, the sea is barely 20 miles away.
Thus, strange as it was to think about how water shortages might affect coal-fired power generation while standing atop Hoover Dam, it was more worrying to think about the following confluence of factors:
Coal is being used extensively worldwide as a source of energy. In India and China, 70 percent to 80 percent of electricity is coal-based.
Burning coal is a major source of carbon dioxide, an agent for global warming and climate change.
Huge quantities of water, often groundwater, are needed to sustain coal-based power generation.
Water is absolutely necessary for life on this planet, and there are enough data trends to justify worry about the future availability of water — especially groundwater.
Therefore, instead of urging countries, particularly India and China, to stop using coal, perhaps we ought to focus on how to a large extent it is all about water. Many parts of India, China and other countries have low levels per capita of available water. For instance, while the United States has about 1,600 cubic meters of water per person, the average in China is about 400 cubic meters, and even less in India. This immensely valuable resource can be put to better uses than in coal-fired power plants.
This is but another incentive for us to explore alternative energy sources that do not impose additional demands on water, which will then also mean lesser reliance on coal. Water-constrained countries such as China, India and Israel ought to encourage innovation on this urgent issue.
At the same time, we here in the United States have a wonderful opportunity to use our research and development infrastructure to develop feasible and economical approaches that will ease the pressure on water resources, and thereby help the world.
After all, to borrow a water metaphor, we sink or sail together!
For The Register-Guard
Posted to Web: Sunday, Apr 5, 2009 04:29PM
Appeared in print: Monday, Apr 6, 2009, page A7
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