Singing the desalination global warming paradox blues

Climate change could make California desperately thirsty for desalted water. But powering up the desalination plants could cause more global warming

Published April 18, 2007 9:37PM (EDT)

One need not stray too far from the San Francisco Bay Area when searching for up-to-date status reports concerning the intersection of energy policy and environmental protection. On Wednesday morning, the San Francisco Chronicle reported that Berkeley's women/worker-owned biodiesel collective, the Biofuel Oasis, is opening a four-pump fueling station less than a mile from my own house. Earlier this week, SustainLane.com reported that the city of Oakland provides its citizens "with the highest percentage of power produced from renewable energy" of any of the top 50 largest cities in the United States -- 17 percent, some of which is generated by the wind turbines on the Altamont Pass, which I have driven through countless times on my way to and from Los Angeles or the Sierras. And on Monday, the Food & Water Watch blog reported an intriguing paradox in Marin County concerning a proposed desalination plant.

The problem: the Marin Water District recently committed to reducing its greenhouse gas emissions by 15 percent from 1990 levels. But desalination plants consume oodles of energy -- thus contributing to increased CO2 emissions.

Food & Water Watch:

It's way past ironic that cities concerned about drinking water shortages in drought, which may be worsened by global warming, are even considering technologies like desalination, whose emissions could make global warming worse.

Marin being Marin, the water board president has proposed that the desalination plant be powered by solar power or some other combination of renewable energy. But that raises a separate set of problems. According to "Desalination, with a Grain of Salt: A California Perspective," an authoritative report published in June 2006 by the Oakland-based Pacific Institute for Studies in Development, Environment, and Security, the costs of providing water from very best, most efficient, cheapest-to-run desalination plants are greater than what urban consumers of water currently pay in California. And that's before calculating in the additional costs incurred by using electricity generated from solar or wind power, which, right now, is more expensive than electricity produced from burning fossil fuels.

Food & Water Watch, which describes itself as "committed to creating an economically and environmentally viable future" and "working with grassroots organizations and other allies around the world to stop the corporate control of our food and water," is strongly opposed to desalination technology. Their Web site even includes a list of the top ten reasons to oppose the construction of desalination plants, including a grab-bag of everything from environmental justice considerations to impacts on marine biota.

Disconcertingly, however, the number one reason on their list is the highly misleading declaration that "It doesn't work," which, best I can tell, from reading the Pacific Institute's 100-page treatise on the topic, simply isn't true. There are numerous countries with working desalination plants providing drinking water for their citizens, particularly in the Mideast, Persian Gulf, North Africa, and the Caribbean.

From the Pacific Institute:

By January 2005, more than 10,000 desalting units larger than a nominal 0.3 million gallons per day ( MGD) had been installed or contracted worldwide. These plants have a total capacity to produce about 9,500 MGD of fresh water from all sources. In 2000, the cumulative installed desalination capacity was around 6,900 MGD, implying a growth rate of around 7 percent per year.

Food & Water Watch qualifies their assertion by saying that:

The main desalination technology being proposed in the United States is reverse osmosis, a process by which highly pressurized saltwater is pushed through tiny membrane filters in order to produce drinkable water. This technology has yet to work on a large scale in this country. Although there are working projects around the world, they have limited environmental requirements and different site conditions that make it feasible.

I suppose we can argue about what constitutes "scale," but again, according to the Pacific Institute report, the United States is responsible for 17 percent of global production of water via desalination, and nearly 70 percent of U.S. production is from reverse osmosis technology, which the report calls "a relatively mature technology" that "is experiencing rapid growth."

I'd be pretty annoyed if I went into a debate on the pros and cons of desalination technology armed with Food & Water Watch's talking points and had Pacific Institute's statistics thrown back in my face. Which is too bad, and itself "way past ironic," because if you read the Pacific Institute's report, you will find plenty of very good reasons to oppose charging ahead with desalination technology. In fact, you will be quite well-armed to debate any aspect of the question, from appropriate strategies for environmental mitigation to the advantages and disadvantages of municipally-run systems vis a vis those produced by private water companies.

The real challenge is not that desalination doesn't work. The industry has experienced constant technological improvement and production costs have been dropping for years (although cheap oil played a significant part in that, which doesn't augur well for cost-benefit analyses conducted with an eye to the future). With enough public input into the process, appropriate assessments of environmental impacts, and corresponding efforts at conservation and the reduction of waste, there could well be a smart way to pull it off. Marin, which undoubtedly enjoys one of the higher environmental-activist-per-square-mile ratios of any county in the United States, could be the perfect test case for doing it right.

It certainly won't be easy. Once more, from the Pacific Institute report:

Among the exceptions may be desalination proposals where alternative water-management options have been substantially developed, explicit ecosystem benefits are guaranteed, environmental and siting problems have been identified and mitigated, the construction and development impacts are minimized, and customers are willing to pay the high costs to cover a properly designed and managed plant... In the end, decisions about desalination developments will revolve around complex evaluations of local circumstances and needs, economics, financing, environmental and social impacts, and available alternatives."

That's not quite as sexy as saying "It doesn't work." But it's a lot more convincing.


By Andrew Leonard

Andrew Leonard is a staff writer at Salon. On Twitter, @koxinga21.

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