"Mounting studies highlight greenhouse gas emissions from reservoirs, and now a coalition of environmental groups has called for regulatory action."
"This month regulators greenlighted a transmission line that would bring power generated from Canadian hydroelectric dams to New York City. New York’s plan to achieve a zero-emissions grid by 2040 depends on hydropower, and it’s not alone.
Globally hydropower is the largest source of renewable energy. In the United States it makes up 7% of electricity generation, and 37 states allow some form of hydropower in their renewable portfolio standards, which establishes requirements for the amount renewable energy that must be used for electricity generation.
As U.S. states and countries across the world work to reduce fossil fuels and boost renewables, hydropower is poised to play an even bigger role.
There’s just one problem: A growing body of research published over the past two decades has found that most reservoirs, including those used for hydropower, aren’t emissions-free."
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