Hydropower – an environmental battleground

About three-quarters of the renewable electricity produced in the EU today comes from hydropower.

Austria relies heavily on hydropower and is the only EU country currently getting more than half of its electricity from renewables. And just outside the EU, Norway gets nearly enough energy from hydropower to supply its 4.6 million citizens with electricity without drawing on its vast oil and gas reserves just off the coast. But this has not been enough to persuade environmentalists to take hydropower to their hearts.

The conservation group WWF successfully campaigned against Croatian proposals to build a 138 megawatt (MW)hydropower plant on the border with Hungary, saying they would be "an ecological disaster". The Novo Virje dam is now on hold until at least 2020.

As Nelson Mandela once remarked, controversy surrounding the benefits and perils of building dams has made hydropower "one of the battlegrounds in the sustainable development arena".

But whatever the environmental doubts, last week, as part of its proposals to improve the infrastructure of Africa, the European Commission lent its support to hydropower projects on that continent.

Hydropower harnesses energy from falling water and converts this to electricity. A single site can generate several hundred MW of electricity, compared to about 2MW for a large modern wind-turbine.

In the process, however, it can permanently destroy wildlife and fishing grounds. Flooding land to build a hydroelectric dam can also mean emissions of methane, a gas linked with global warming, from decomposing plants and trees.

Small hydropower plants, defined by Greenpeace as having a capacity of less than 10MW, are an environmentally acceptable option, but unlikely to solve the EU's energy problems.

Mahi Sideridou of Greenpeace is philosophical about the best way forward for hydropower. In Europe, the potential for large-scale hydropower has largely been used up, she said, and the damage was mainly done when the dams were being built.

"Now they're up and running we might as well let them continue," Sideridou suggested, "since they contribute to the energy mix in a more sustainable way than other options."

Greenpeace has for now turned its attention to the problem of making sure careful social and environmental impact assessments are carried out on large hydropower plants in developing countries.

"Sometimes these projects are carried out in a highly inappropriate manner," said Sideridou. "We have to make sure there is no risk of indigenous populations near a hydro plant being dislocated."

About three-quarters of the renewable electricity produced in the EU today comes from hydropower.

• Primary Source