Renewable energy projects will devour huge amounts of land, warns researcher

Large-scale renewable energy projects will cause widespread environmental damage by industrialising vast swaths of countryside, a leading scientist claims today. The warning follows an analysis of the amount of land that renewable energy resources, including wind farms, biofuel crops and photovoltaic solar cells, require to produce substantial amounts of power.
Jesse Ausubel, a professor of environmental science and director of the Human Environment programme at Rockefeller University in New York, found that enormous stretches of countryside would have to be converted into intensive farmland or developed with buildings and access roads for renewable energy plants to make a significant contribution to global energy demands.

Prof Ausubel reached his conclusions by ranking renewable energies according to the amount of power they produce for each square metre of land. The assessment allows direct comparison between the different approaches, based on the impact they will have on the surrounding landscape.

The analysis showed that damming rivers to make use of hydroelectric power was among the most harmful to the landscape, producing around 0.1 watts of power per square metre. The world’s largest dam, the Three Gorges power station on the Yangtze in China, stores nearly 40bn cubic metres of water, submerging land that was previously home to more than 1 million people.

Biofuel crops and wind energy fared better in the study, with both generating around 1.2w to a square metre. Leading the renewable energy sources were photovoltaic solar cells, which use sunlight to create electricity, at around six to seven watts to a square metre.

Prof Ausubel investigated how much land renewable energies would need to provide electricity for large populations and compared them to output from nuclear power stations.

In one example he showed that damming rainfall and flooding the entire Canadian province of Ontario would generate hydroelectric power equivalent to 80% of that produced by the country’s 25 nuclear power plants.

Another calculation revealed that to meet US energy demands for 2005 with wind power would require constant winds blowing onto wind farms covering more than 780,000 square kilometres of land, the area of Texas and Louisiana combined. A comparison of solar energy with nuclear found that a hectare of photovoltaic cells was needed to produce the same amount of power as one litre of fuel in the core of a nuclear reactor.

The report breaks what Prof Ausubel calls the “taboo of talking about the strong negative aspects of renewables”, by focusing on examples that highlight their limitations. “When most people think of renewables and their impact, they’re mistaking pleasant landscaping with what would be a massive industrial transformation of the landscape,” he said.

Guardian