An editorial in the New York Times last week highlighted a topic I've been meaning to comment on for some time, the gradual demise of our oldest and still largest source of renewable energy: hydroelectric dams. Along with lauding plans to remove several West Coast dams in order to protect fish populations, the Times urged the dismantling of the four large power dams on the lower Snake River in Washington state. The disconnect between that position and the paper's long-standing advocacy of stronger measures to address climate change is remarkable, considering the elimination of 3,000 MW of zero-emission power generation that would accompany the loss of these dams. But if the unpopularity of existing hydropower dams in environmental circles explains the exclusion of this vital energy resource from the definition of "qualified renewables" included in the proposed national Renewable Electricity Standard (RES) of the Waxman-Markey climate bill, that hardly excuses a policy so counter-productive for our efforts to reduce greenhouse gas emissions.

Consider the four dams in question. I can't speak to concerns about declining salmon populations or other habitat issues, though I note that the dams in question are all "run of river" facilities, without large reservoirs. What is clear, however, is that if the four facilities typically operate at the national average hydropower utilization rate of around 36%, their annual power generation would come to about 10 million megawatt-hours (MWh) of electricity, equivalent to the output of 4,000 MW of wind capacity, or roughly 20% of the entire US wind power output in 2008. After a banner year for wind turbine installations in 2008, the US might not add much more new wind capacity than that this year, and wind remains the largest-scale technology among our preferred renewable power options. In fact, since 1999 US hydropower output has declined by an amount greater than the entire current contribution of wind power. That means the emissions benefits of a decade of dramatic growth in wind and solar power have been negated by the loss of hydroelectric generation--a loss that the authors of Waxman-Markey have chosen to ignore by counting in their RES only "incremental hydropower", which they define as

"(A) energy produced from increased efficiency achieved, or additions of capacity made, on or after January 1, 1988, at a hydroelectric facility that was placed in service before that date and does not include additional energy generated as a result of operational changes not directly associated with efficiency improvements or capacity additions; or
`(B) energy produced from generating capacity added to a dam on or after January 1, 1988, provided that the Commission certifies that--
(i) the dam was placed in service before the date of the enactment of this section and was operated for flood control, navigation, or water supply purposes and was not producing hydroelectric power prior to the addition of such capacity;
`(ii) the hydroelectric project installed on the dam is licensed (or is exempt from licensing) by the Commission and is in compliance with the terms and conditions of the license or exemption, and with other applicable legal requirements for the protection of environmental quality, including applicable fish passage requirements; and
`(iii) the hydroelectric project installed on the dam is operated so that the water surface elevation at any given location and time that would have occurred in the absence of the hydroelectric project is maintained, subject to any license or exemption requirements that require changes in water surface elevation for the purpose of improving the environmental quality of the affected waterway."

In other words, a utility would be able to count increases in hydropower towards its RES compliance derived only if they came from certain carefully-specified improvements, while the sole penalty for lost hydropower capacity and output would be an increase in the base amount on which the RES would be calculated. So at the full 20% RES level for 2020 and beyond, a MW of new wind, solar or other "qualified renewable" capacity would count 5 times as much as a MW of hydro dismantled.

This mismatch speaks to our conflicted attitudes toward climate change and the broader issues of sustainability. I'm sure that those advocating the removal of these dams would argue that we shouldn't make such decisions on the basis of any single criterion, even one as important as greenhouse gas emissions. Yet that view is at odds with the underlying philosophy of a climate bill that aims to do more than just level the playing field by imposing a charge on greenhouse gas emissions to account for the environmental externality not captured in the economics of the energy market. In addition to its skewed version of cap & trade, Waxman-Markey would stack the deck for a chosen group of renewable energy technologies, in the process excluding the one that produces more zero-emission MWhs than all the rest put together. When the Senate takes up this legislation, it should abandon this narrow focus on specific technologies in favor of one that creates a positive bias for all our low-emission sources, including hydropower and nuclear energy. For a government so determined to demonstrate our seriousness about tackling our emissions, in advance of December's Copenhagen climate conference, that would speak far more loudly than another thousand-plus pages of convoluted new regulations.

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