Study finds climate impact of hydropower varies widely

Upper reservoir (Llyn Stwlan) and dam of the Ffestiniog Pumped Storage Scheme in north Wales
[credit: Arpingstone/English Wikipedia]

Of course this all depends on what is being claimed to be ‘climate impact’. If certain trace gases (note the word: ‘trace’) are not the unlikely mega-force that they are claimed to be by climate alarmists, this Green Car Congress article is more or less redundant.
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Although hydropower is broadly considered to be much more environmentally friendly than electricity generated from fossil fuels, a new study by a team at Environmental Defense Fund finds that the climate impact of hydropower facilities varies widely throughout the world and over time, with some facilities emitting more greenhouse gases than those burning fossil fuels.

The researchers report their results in an open-access paper in ACS’ journal Environmental Science & Technology.

Currently, hydropower contributes two-thirds of the electricity generated from renewable sources worldwide, according to the International Energy Association, with thousands of new hydroelectric facilities either planned or under construction across the globe.

This popularity stems partly from the perception that hydropower is an environmentally friendly alternative to fossil fuels.

It is commonly thought that the greenhouse gas emissions from hydropower plants are similar to those of wind-generated power facilities.

However, most studies of hydropower’s climate impact have neglected certain factors, such as changes in carbon dioxide emissions that occur when natural landscapes are flooded to create reservoirs for hydropower plants, as well as the near-term warming from associated methane emissions.

Ilissa Ocko and Steven Hamburg of EDF wanted to conduct a more comprehensive analysis of the climate impacts of hydropower facilities over time.

They analyzed the climate impacts over time of carbon dioxide and methane emissions from a dataset of 1,473 hydroelectric facilities in 104 countries. They also estimated emissions caused by flooding the reservoir.

The team found that hydropower emissions on average were far greater and thus worse for the climate than emissions from nuclear, solar and wind power installations, but better for the climate than emissions from coal and natural gas utilities.

Full article here.