Depending on location, hydroelectric power can have (mostly because of decomposing vegetation) carbon-equivalent emissions ranging from several grams of CO₂ per

Depending on location, hydroelectric power can have (mostly because of decomposing vegetation) carbon-equivalent emissions ranging from several grams of CO₂ per kWh, all the way up to around two thousand grams (!) per kWh. This greatly depends on location, with shallow, large-area tropical dams being the worst offenders, and cold, high altitude Nordic dams being the most environmentally friendly.