Virtually no source of energy can claim to have zero impact on biodiversity. Fossils fuels are the obvious worst offenders, as their burning emits gases which contribute to climate change and desertification. Nuclear accidents and oil spills, meanwhile, can decimate wildlife, as recent examples have shown.
However, even renewable sources of energy can pose problems. Wind turbines can upset the migratory patterns of birds and have triggered protests among some rural communities for causing noise or spoiling pristine landscapes.
The issue of deforestation directly or indirectly caused by the cultivation of biofuel crops has proven divisive within the industry, and has stirred a huge debate on the green merits of agri-fuels. Hydroelectric dams, which still account for the overwhelming majority of renewable electricity production, require flooding local habitats.
Solar energy appears to be largely free from these problems, a fact industry proponents are keen to emphasise. In December of last year, the German Renewable Energies Agency, with the backing of German ministry of the environment and private renewable energy companies, published a study on the benefits of solar parks to biodiversity.
The study found that "as well as making an important contribution to future energy supplies, solar parks can also provide a refuge for plants and animals".
Similarly, many environmental activists have enthusiastically backed solar energy for its low impact on biodiversity. Speaking to EurActiv, Friedrich Wulf, a biodiversity campaigner at Friends of the Earth Europe (FoEE), said that of the major energy sources "solar energy so far has the least impact on biodiversity".
Efficient land use is among the credentials put forward by the industry. Large solar parks tend to thrive on deserts, abandoned land or former industrial sites, with a minimum impact on biodiversity.
"We are against putting photovoltaics in high productivity land" such as agriculture land, the secretary-general of the European Photovoltaic Industry Association (EPIA), Eleni Despotou, told EurActiv. "We are promoting large systems in areas such as deserts or former mining or industrial sites, where land cannot really be exploited. These can be excellent fields for large-scale PV farms."
For FoEE's Wulf, however, small-scale decentralised installations are preferable to large solar parks from an environmental viewpoint. "Sometimes you have acres of fields of solar panels, obviously that's not as good. But it is decentralised in many cases, you can just put it on your roof, so there is a lot of potential there," he said.
Impact on water supplies is also negligible, according to Despotou. Solar panels do not need frequent washing, "except if there is a sand storm from North Africa," she said. "It might happen if you are in Greece or Italy for instance, you might have some sand. But apart from this, no."
Few studies
Others, however, are more cautious. Bruce Robertson, a researcher with the University of Michigan's Kellogg Biological Station, said "there are very few published studies of the impact of solar energy on plant and animal life. I've never seen anything like it".
Last year Robertson conducted a study in Hungary with local environmental research institutions which found that solar panels could pose as a "false habitat" for up to 300 species of aquatic insects.
The latter were found to confuse the reflective surface of the panels with water, leading them to deposit their eggs there. The resulting reproductive failure might have knock-on effects throughout the food chain, the study said.
Regarding desert-based solar power facilities, "they're simulating water in the most water-poor environment in the world. It would be very surprising if there wasn't an impact on animals that use polarised light to find water".
Craig Winneker, media relations manager with the European Photovoltaics Industry Association (EPIA), defended the industry's record on biodiversity protection. Responding to the University of Michigan study, he said: "the industry is looking at its effect on biodiversity and is adopting best-practice guidelines to ensure that biodiversity is protected and that installations are put in the most suitable locations".
