In discussions about clean energy (CE), solar and wind often get mentioned more than other sources. But a number of other options are available to help utilities and jurisdictions reach their CE goals and to help the world reduce its carbon emissions output. For example, battery storage is gaining momentum as it becomes more practical and less expensive.

Hydro power also has a lot of potential to contribute to CE goals, especially given that it’s already widely used. In addition, hydro power “can help get more wind and solar on the grid,” according to Argonne National Laboratory.

At the same time, the Environmental Defense Fund (EDF) states that “hydropower…is not always as good for the climate as broadly assumed,” given that “the reservoirs where water is stored…produce both carbon dioxide and methane” and that some “have carbon footprints equal to or greater than, fossil fuels.” The EDF warns that developers must take the ratio of reservoir size to the amount of power generated and other factors into consideration rather than assume that “hydropower is universally low-carbon.”

Additionally, hydro transmission has met challenges from those who say proposed projects would negatively impact areas where transmission lines are proposed to be built or wouldn’t bring the benefits of the transmission to those areas. The following examples demonstrate these potential benefits and obstacles.

New England Clean Energy Connect

In early 2020, the Land Use Planning Commission (LUPC) of Maine and the Maine Public Utilities Commission (MPUC) approved the development of a $1 billion transmission line, known as the New England Clean Energy Connect (NECEC), which would bring hydro power from Quebec, Canada to Maine to provide power in the region. The Central Maine Power (CMP) project promises to allow up to 1,200 MW of power to reach Massachusetts’ regional power grid and help it meet CE goals.

However, citizens have complained that the path of the transmission line through CMP-owned property would harm wilderness areas, diminishing recreation, scenery, and resources, while not reducing pollution. Supporters of the project have argued that the benefit of considerably reducing carbon emissions in the area outweighs the negative consequences.

Champlain Hudson Power Express

In a similar project, the proposed Champlain Hudson Power Express (CHPE) transmission line is expected to deliver 24,000 MWh of hydro power to New York, from Quebec. Officials say the project is part of the city’s transition to CE power sources, and now is the perfect time to initiate such a project, as the Indian Point Energy Center, a nuclear power plant station, is due to shut down next spring.

But critics point out that, although the project can help meet CE goals in the long run, it may increase the city’s dependence on fossil fuels over the next few years. Additionally, having the transmission line cable burrowed into the Hudson River’s riverbed may cause problems with the river’s ecosystem.

Is your utility involved in any hydro power projects? If so, what are the potential benefits and drawbacks? Please share in the comments.