Rethinking Hydropower: Infrastructure Based Generation

By Russell King, 2L Staff Editor, Vermont Journal of Environmental Law

            Anthropogenic climate change is one of the world’s most pressing concerns. Conservative estimates show a societal cost of carbon that rises to $95 per ton by 2050, culminating in a yearly loss of 23% of the world’s GPD by 2100. This figure only considers economic losses—loss of coastline, ecosystem collapse, and other catastrophes are not considered. Nor does this figure incorporate other greenhouse gasses, such as methane or sulfur oxides. Simply, disaster looms for humanity. America is the world’s second largest emitter of greenhouse gasses, and thus bears a proportional responsibility for abating climate change.

The energy sector, which produces approximately one third of America’s greenhouse gas emissions, provides a place to start in the fight against climate change. America will still need electricity, so replacing fossil fuel fired generation with low to zero carbon sources is the only option in the long run. Renewable energy takes many forms, with the three most common being solar, wind, and hydropower. Each of these has the benefit of producing no carbon when generating electricity. Each comes with drawbacks as well. Solar has a low capacity factor of about 28% to 15%, which means that a 100kW solar facility only produces 28kW to 15kW on average. Wind sees similarly low capacity factors. Solar and wind are both intermittent resources, meaning they generate electricity only when the sun shines or wind blows. Although hydropower—particularly small-scale hydropower—has a high capacity factor and is less intermittent than wind and solar, it disrupts streams and rivers, and may even increase methane emissions. Renewable energy can help solve climate issues, but there is a tradeoff: either we accept intermittency and low capacity factors, or we drown our valleys and block our streams.

There is one readily available renewable resource that does not force a choice between reliable power supply and ecosystem destruction: infrastructure based hydropower (IBH). Unlike traditional hydropower (e.g., the Hoover Dam), IBH does not require a new dam. Instead, it comes in two forms: additions to currently existing dams for another needed purpose, such as flood control; or conduit-based hydropower, which adds generation to a conduit needed for another use. IBH that uses dams has the same environmental impact as that of the dam; however, the impact comes with an additional benefit. For example, a dam needed to prevent floods from destroying a town could also generate carbon-free electricity, significantly increasing the benefit-cost ratio. This particular form of IBH ha a lot of potential: there are 167 dams in NY alone just for flood control. Conduit hydropower has even less of an environmental impact. Conduit hydropower is the addition of generating capacity to preexisting manmade conveyance. The Hydropower Regulatory Efficiency Act (HREA) creates a simple permitting process to install hydropower on agricultural, industrial, or municipal conduits. IBH means renewable energy is as simple as a turbine in a local farmer’s irrigation system, a town’s municipal water supply, or a city’s flood control dam.

The specter of climate change demands answers. One of those answers is renewable energy—by eliminating the greenhouse gasses from electricity generation, America can reduce its emissions by up to a third. Not all renewables are created equal, however—solar and wind have greater intermittency and lower capacity factors than hydropower; hydropower is more environmentally damaging than solar and wind. However, there is one form of hydropower that is the best of both worlds—IBH. Simply install a turbine onto a flood control dam or an irrigation system and it makes carbon-free power. As America searches for answers to the growing issue of climate change, every solution must be considered, even rethinking America’s oldest form of renewable energy.