The sandy seabed off the coast of Belgium is not exactly teeming with life. Cleared of oyster beds through over-fishing in the 19th century, the area is described as exhibiting “naturally poor seafloor communities” by the Belgian marine research group Marine@UGent.
But in this underwater desert are submarine gardens teeming with blue mussel, anemones, amphipods and more. These oases are the foundations of offshore wind farms, which now number a dozen in Belgian waters. And the presence of life there is important in a growing debate about clean energy and biodiversity.
Like almost any human activity, clean energy production has impacts on the natural environment. There is no question that wind turbines can kill birds and bats, for example. And concentrated solar power towers have also been linked to bird deaths, while any energy infrastructure development can affect sensitive habitats.
The question is how serious these losses are—and how they can be minimized. But before digging into the data on this, it helps to have some context. One of the prime motivations for clean energy infrastructure investment and development is to reduce greenhouse gas emissions from fossil fuel systems.
This reduction, in turn, aims to curtail global warming—which is already a major contributor to a loss of biodiversity so extensive that scientists are referring to it as the sixth mass extinction, comparable to the meteorite strike that wiped out the dinosaurs.
Measured against climate change, the biodiversity threat from building clean energy plants seems almost trivial.
An example: a study by the University of California, Davis, found that building wind and solar plants in the desert could reduce the habitat of the emblematic Joshua tree by 1.7% come 2070, while endangered San Joaquin kit foxes would lose 3.9% of their natural environment.
But climate change, even under a moderate emissions scenario, would reduce these habitats by 31% and 81%, respectively. In other words, renewables are not great for the Californian desert environment, but climate change—at least for Joshua trees and kit foxes—is more than 18 times worse.
It is because of this that a report by the Coalition Linking Energy And Nature for action (CLEANaction) emphatically found that all forms of renewable power are better for nature than fossil fuels.
“CLEANaction confirms that even when the full range of environmental impacts—from sourcing raw materials to final operation—is considered, generating and storing energy from renewables is far less environmentally damaging than using fossil fuels,” says CLEANaction’s WWF.
It is also useful to consider clean energy biodiversity impacts in relation to those caused by other types of human activity. In 2022, for example, wind turbines caused an estimated 1.2 million bird deaths in the US.
The figure represents a tragic biodiversity loss but was almost nothing compared to the 6.6 million birds killed by hitting mobile communication towers, the 67 million poisoned by pesticides or the 200 million crushed by cars, let alone the 599 million wiped out by collisions with buildings or the 2.4 billion massacred by cats.
That’s right: for every bird killed by a US wind turbine, 2,000 are killed by the nation’s cats. Notably, however, the people who call for a halt to clean energy projects because of alleged wildlife impact concerns rarely campaign for the eradication of domestic cats.
Responsible clean energy buildout supports biodiversity
That said, scrutiny of clean energy projects on conservation grounds has had a positive effect: the renewables industry is arguably more conscious of its impact on the environment than any other industrial sector—and is working hard to improve biodiversity instead of curtailing it.
Wind farm developers are a particular focus for wildlife concerns and have come up with various methods for minimizing bird and bat strikes. These range from moving turbines away from flight corridors and shutting them down when species are near to playing alert noises and using dark paint on rotor blades.
But one of the biggest ways of reducing wind-induced wildlife mortality is through something the wind industry is doing as a matter of course: installing bigger turbines. Repowering turbines at California’s notorious wind-kill black spot, Altamont Pass, helped cut fatalities by 65%.
Such improvements in preservation rates are unheard of in other industries, yet commonplace in clean energy. Indeed, most environmental bodies are in favour the responsible buildout of renewables because of their potential benefits to wildlife.
For example, the Audubon Society in the US “strongly supports” properly sited photovoltaic solar power. “As with most renewable energy sources, the benefits to birds by reducing carbon emissions outweigh other concerns, as long as the installations are built with care,” it says.
“Our own science shows that unless we slow the rise of global temperatures, two-thirds of North America’s birds could face extinction. Renewable energy, like solar power, is key to reducing pollution and holding temperatures steady. This not only protects birds, but also communities that are vulnerable to the effects of climate change.”
Committed to net biodiversity gains
Battery projects usually pose even less of a biodiversity risk because the plants require relatively little space and can be built on brownfield or degraded sites.
Nevertheless, responsible developers such as Pacific Green are committed to ensuring there is a net biodiversity gain with every project, for example by setting aside or restoring nearby habitats to compensate for the land taken up by a battery system.
The work on how to ensure clean energy helps rather than harms biodiversity is ongoing but there is already a growing body of policy recommendations and best practice, such as avoiding sensitive habitats, minimizing construction and operation impacts, and compensating—or over-compensating—for any negative effects.
“Scaling up renewable power while halting and reversing biodiversity loss demands an integrated approach that capitalizes on synergies, minimizes trade-offs and averts unintended consequences,” says the Organisation for Economic Co-operation and Development in its own set of policy guidelines.
“Effective biodiversity mainstreaming not only mitigates adverse impacts on biodiversity, but can also expedite renewable power permitting, reduce project delays and cancellations, and avoid greenhouse gas emissions from ecosystem conversion.”
Publish date: 30 July, 2024