Solar farms have the potential to solve our energy problems. However, many subtly modify the environment around them. Sometimes these changes are beneficial, like a Chinese solar farm greening a desert. But changing the environment always carries risk, especially when it comes to endangered species.
In 2025, a conservation advisory group published an article about the dangers of Overnight Solar, a proposed solar farm in San Bernadino, California. According to the newspaper, the facility could pose a huge threat to the local desert tortoise, an animal considered endangered under California’s Endangered Species Act. One study found that solar farms produce a “heat island” effect that increases the earth’s surrounding temperatures. Ironically, the danger comes from the shadow of these solar panels.
Although solar panels installed above canals can provide shade that reduces surface evaporation, in the desert, solar panel shade temperatures are higher than normal shade temperatures. This is where turtles come in. According to the study, these higher temperatures can make it harder for turtles to retain water. This may not pose a problem for adult desert tortoises, but it poses a serious risk of dehydration for hatchlings and juveniles due to their small size and higher surface area to volume ratio. While the coalition of conservation councils is not opposed to the Overnight Solar Energy project per se, they would prefer that the facility (or turtles) be relocated to minimize any potential threat to the population.
Overnight Solar isn’t the only solar farm threatening turtles
The desert tortoise, although endangered, can be found throughout the southwestern United States. As the name suggests, anywhere there is a desert in the United States, you might find a desert tortoise. Unfortunately, Overnight Solar isn’t the only project attempting to install solar panels in a desert, threatening desert tortoises.
Earlier this year, the California Energy Commission approved a $700 million project to build a large solar farm next to (but not on) the Mojave National Preserve. That facility, called Soda Mountain Solar, will span nearly 3,000 acres, but it will be right in the middle of migration routes for animals such as the desert tortoise and bighorn sheep. The planned location poses a problem for both populations, as desert tortoises have lost much of their natural habitat. Meanwhile, bighorn sheep rely on this “migratory corridor” to move between mountains – a process that keeps their population healthy.
Although the California Energy Commission says Soda Mountain Solar’s final plan incorporates ideas that reduce any potential threat to local animal habits to “less than significant,” many scientists who raised these concerns have doubts. According to environmental advocates, the commission has not implemented any of the suggested measures. More importantly, approval went over the heads of the Desert Renewable Energy Conservation Plan, which is supposed to have the final say on where – and where not – to install solar farms in the desert. However, the Soda Mountain Solar Farm is not yet built, as California’s Bureau of Land Management must give approval before construction begins.
