HOW GREEN IS GREEN ENERGY 15 - JULY - 2020

Renewable energy is an important piece of the puzzle in meeting growing energy demands and mitigating climate change, but the potentially adverse effects of such technologies are often overlooked. Given that climate and ecology are inextricably linked, assessing the effects of energy technologies requires one to consider their full suite of global environmental concerns. We review here the ecological impacts of three major types of renewable energy – hydro, solar, and wind energy – and highlight some strategies for mitigating their negative effects. All three types can have significant environmental consequences in certain contexts. Wind power has the fewest and most easily mitigated impacts; solar energy is comparably benign if designed and managed carefully. Hydropower clearly has the greatest risks, particularly in certain ecological and geographical settings. More research is needed to assess the environmental impacts of these ‘green’ energy technologies, given that all are rapidly expanding globally. Trends Renewable energy is expanding rapidly. Growth is greatest in China, which now constitutes 28%, 26%, and 35% of the global capacity of hydro, solar, and wind power, respectively. Hydropower has the largest environmental impacts, mostly because of habitat loss and fragmentation caused by impoundment reservoirs and roads needed for dam construction and maintenance. Dams block animal migration and disrupt river flows, creating homogenized conditions favoring non-native species. Hydropower also generates greenhouse gases, especially methane, particularly in the tropics. Wind power kills 100 000 s of birds and bats every year. Wind farms can affect bird migrations and trigger population declines. Wind turbines increase ambient temperature and noise, harming some native species. Solar energy is the fastest growing renewable, but its impacts are poorly known. More research is needed in this area. Author: Luke Gibson,Elspeth N. Wilman,William F. Laurance Publication: Trends in Ecology & Evolution Publisher: Elsevier Date: December 2017