Are we sacrificing our forests for solar?

If you’ve ever driven along the highway and passed a large field of solar panels, you’ve probably seen a solar farm. There can be hundreds or even thousands of panels in these energy powerhouses. 

Solar farms aren't the same as residential or commercial solar installations. Instead of directly using the electricity they generate onsite, solar farms send it to the grid. From there, the utility distributes that energy to all of its customers, providing communities with a sustainable source of power that reduces reliance on fossil fuels.

But some scientists claim that solar farms take up too much already scarce land. So, do these solar farms do more harm than good?

Solar farms are large-scale ground-mounted solar panel systems. They can help us achieve climate goals, but they require vast open spaces. Where do we find these expansive spaces? In many cases, we build them—sometimes at the expense of natural land.

That’s why it’s important to understand the benefits and potential downsides of solar farms, and how they can harness solar energy without harming the natural land they’re built on. If they're not designed thoughtfully, thousands of acres of forest could be cleared in the name of solar, defeating the purpose of investing in clean energy to begin with.

Solar farms are key to replacing fossil fuels

Solar farms reduce the grid’s reliance on fossil fuels by replacing them with solar-generated electricity. Think of the grid like a bathtub: One faucet is renewable energy and the other is fossil fuels. Either faucet can fill up the tub—but right now, we have the fossil fuel faucet on full blast. In 2023, only 21% of electricity came from renewables. 

If we want to keep the lights on, we need to keep our metaphorical bathtub full. To be able to turn down the fossil fuels faucet, we need to first turn up the renewable energy faucet. Solar farms are an excellent way to do this.

Why do solar farms concern some scientists?

Supporting solar energy is one of the best ways to reduce carbon emissions and mitigate climate change. But current practices aren't doing enough to curtail their negative effects on natural land, and scientists have raised concerns about the impact solar farms could have on forests and farmland.

In 2023, Mass Audubon, the largest nature-based conservation organization in New England, and the Harvard Forest Department published a report on whether solar farm development has to come at the cost of nature.

The researchers found that since 2010, 5,000 acres of forest and farmland in Massachusetts have been replaced by large-scale solar farms. In a separate 2020 study, Mass Audubon found that over a five-year period, Massachusetts lost an average of 13.5 acres per day to development; around one-quarter of this loss was related to solar. 

While those numbers represent progress on the solar front, they often come at the expense of otherwise valuable land. But it doesn't need to be that way.

When it comes to protecting the environment, it shouldn't be expanding clean energy or preserving natural land... it should be both. Biodiversity, air and water quality, weather resiliency, and slowing climate change are all dependent on healthy forests and farmland—and vice versa.

While Mass Audobon's 2023 study highlighted the dangers of clearing valuable land for solar, it also showed that it's possible to responsibly invest in solar farms without damaging the environment. In fact, doing so is "imperative to meeting the state’s climate targets," according to the authors.

Researchers used geospatial data, maps, and energy modeling tools to identify where solar farms could be located based on legal and physical limitations. Then, they assessed how economically attractive projects would be based on their location and scope.

The results showed that communities can prioritize economically viable solar farm development while avoiding sites with high-carbon and high-biodiversity forests. Massachusetts, for example, has enough space for solar in areas that would protect the environment and allow the state to hit net zero goals by 2050.

These sites we should be turning to for solar development are called low-impact areas. 

What are low-impact areas for solar farm development?

Low-impact areas generally include locations that are multi-purpose or otherwise unusable for natural land. Here are some examples:

Agrivolatics benefits agriculture and solar

Choosing solar farm locations with multi-use purposes can result in better financial returns for developers—and better benefits for communities.

For example, agrivoltaics combines solar and agriculture. Farmers can plant crops under solar panels to maximize land use, retain soil moisture, and increase panel efficiency through transpiration's cooling effects.

Agrivoltatics can also promote healthy pollinator populations by growing native meadow habitats and provide ideal grazing habitat for livestock with ample shade.

Size matters

When land needs to be cleared for solar farms, the impact shouldn't be concentrated in one location. We can lessen the burden by developing more but smaller systems and spreading them out.

Mass Audobon's study revealed that 37% of forests cleared for solar were located in south-central Massachusetts. This inequitable approach to building solar means certain communities are losing the benefits of forests and farmland more than others.

The current trajectory of building solar on forested land is counterproductive to meeting net zero goals.

"Transitioning to clean electric power in less than three decades is an absolute imperative for decarbonizing our economy," said Mass Audobon, but "Urgency on climate action... does not justify the haphazard approach to solar deployment."

Solar farms are critical for the protection of exactly the same things they can hurt. It may take extra measures, but creating sustainable solar farms is not only possible—it's necessary.