Itaipú Dam. Image credit: Escuela de Organización Industrial
Hydropower – the energy generated from flowing water – is renewable and emits relatively low amounts of carbon dioxide. Many see the expansion of hydropower as a way to offset fossil fuel-derived energy. In keeping with its green nature, environmental regulations exist to minimise the ecological impact of hydropower plants and to guide their construction and operation.
Counterintuitively, these same regulations may be responsible for an increase in carbon emissions. The regulations meant to keep a hydropower plant’s environmental impact small, also make these plants costly to build, run and maintain. The result is that utility companies that might otherwise invest in hydroelectricity instead choose to pursue environmentally costlier but economically cheaper fossil fuels.
Such are the results of a study by Dr. Edson Severini of Carnegie Mellon University, published on 10 January in PLOS One. In this study, Dr. Severini calculated that each megawatt of fossil fuel-based energy that was installed due to ecosystem preservation regulations that limited hydropower development led to an increase in annual carbon dioxide emissions of roughly 1,400 tons. This is roughly the amount of energy that will get an average-sized car between San Francisco and New York City and the amount of CO2 emitted by 200 individual Americans per year.
Hydropower itself is cheap, compared to energy generated from fossil fuels. The Wisconsin Valley Improvement Company, a natural resources management company, estimates that In the U.S., “hydropower is produced for an average of 0.85 cents per kilowatt-hour (kwh). This is about 50% the cost of nuclear, 40% the cost of fossil fuel, and 25% the cost of using natural gas.”
International Rivers, an environmental NGO, points out that the cost of building dams almost always exceeds initial estimates, often by up to 30% and can take years to build. As a case study, they point to the Itaipú Dam, which cost USD$20 billion and took 18 years to complete. While the costs of energy production may compensate for such high building costs in the long run, such high building costs may not be recovered for many years, which surely affects decisions over which type of power generation to pursue. The further cost of complying with strict environmental regulations can play a decisive role in these decisions.
In his paper, Dr. Severini suggests that future regulations should strike a balance between local environmental concerns and the more global concern of climate change. Current regulations backfired, argues Dr. Severini, because environmental regulations meant to thwart one form of energy didn’t account for what would replace it.
One place to start might be laws requiring the federal government to consider the climate consequences of building any type of power plant. As of now, no such law exists.