Three hundred miles southeast of Stanford in Rosamond, California, rows of solar panels stretch across the Mojave Desert. Wind turbines scatter the slopes at the base of the mountains. Between Joshua trees and desert scrub, oil pumps dip in and out of the sand. Rosamond is a landscape of contrast: a seemingly barren desert wasteland rich in power.
Stanford is now one of many tapping into this wealth. The Stanford Solar Generating Plant, which opened Friday in Rosamond with a ribbon-cutting ceremony, will use more than 150,000 solar panels to generate 67 megawatts of power.
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The 242-acre solar plant is part of the Stanford Energy Systems Innovations (SESI), the University’s energy and climate action plan to reduce carbon emissions by 68 percent by moving from fossil fuels to grid-based renewable electricity sources and implementing a revolutionary heat-recovery system. Other initiatives include the addition of solar panels and efficiency improvements to existing buildings on campus as well as high-efficiency standards for new buildings.
Stanford is not alone in its use of California’s rich solar resources: According to a study by Stanford and the Carnegie Institution for Science, there are 161 planned or operating utility-scale solar power plants in California. More than half of these power plants have been or are being built on previously undeveloped land, totaling about 145 square miles.
The magnitude of these converted lands necessitates the consideration of environmental effects, according to Garry George, renewable energy director at Audubon California.
“[Solar] is a good thing to get really excited about,” George said. “But there’s another thought right after that — what’s the impact?”
Perhaps counterintuitively, the environmental impact can be substantial. Solar projects cover miles of desert landscape in black glass panels, eliminating vegetation and displacing wildlife. According to George, these consequences may be hard to see. “I think most people consider the desert to be barren wasteland,” he said. “But it’s actually one of the most thriving ecologies and [the] most climate-resilient [ecologies] and full of really unusual and unique species.”
In fact, Rosamond is in the heart of a designated globally important bird area because of the variety and concentration of species in that area. The broader Mojave desert ecosystem also hosts a number of rare plants, lizards, desert tortoises and ground squirrels.
Fortunately, there are ways to mitigate the impacts of solar projects on desert ecosystems. The California Environmental Quality Act (CEQA) requires lead agencies to analyze and disclose the environmental impacts that a proposed project will have and implement all feasible measures to alleviate those effects.
For many utility-scale solar projects, most impacts can be mitigated by thorough site analysis. Ideal sites have been previously developed and are not significant conservation or agricultural areas. They are close to existing transmission lines and avoid “wildlife corridors” or important migration routes. If a site is within 5 miles of the foraging habitat for an important or endangered species, the agency must create and preserve new foraging grounds elsewhere. Site selection “should be a very thoughtful planning process,” said George. “Not just any megawatt is great.”
SunPower, the company that Stanford chose to design and build the solar plant, says it has taken steps to ensure that its pursuit of solar energy does not outshine its dedication to addressing potential environmental consequences.
The company uses an approach called “Light on Land,” selecting previously disturbed sites — like the site of the Stanford Solar Generating Plant — when possible. The approach also emphasizes the importance of restoring the land to its original state or better upon conclusion of the project, often by reintroducing native vegetation, which absorbs carbon from the atmosphere and helps retain groundwater.
“There were zero concerns or protests from the environmental community in California about the project,” said Bill Kelly ’85, vice president of SunPower. “We had no pushback from the environmental community in building on this site.”
The unique efficiency of SunPower’s solar panels, a central component of Stanford’s decision to accept the company’s bid, is vital in minimizing the company’s environmental impact. Because its solar panels generate 34 percent more megawatt-hours per acre over their lifespan than its competitors’, SunPower is able to produce an impressive amount of solar power with less acreage, naturally allowing for easier preservation of environmentally sensitive sites.
That’s thanks in part to Stanford ingenuity: SunPower was founded in 1991 by Richard “Dick” Swanson electrical engineering Ph.D. ’74. Later, as a professor at the University, he was paramount in developing the point-contact solar cell. In traditional startup fashion, Swanson eventually resigned from his professorship to start the company.
“Dr. Swanson is a rockstar in the solar community,” said Ingrid Ekstrom, marketing and communications director at SunPower. “He’s known around the world for his advancements in solar technology, which include technologies SunPower installs today.”
Swanson’s advancements and others made by SunPower allow the company’s solar panels to operate efficiently and sustainably. They work better than competitors’ panels in high temperatures, an important innovation in Rosamond, where daily highs average above 92 degrees in the summer. SunPower also uses robots to rid the panels of debris, increasing their efficiency by 15 percent and using 75 percent less water than conventional cleaning methods.
While Stanford’s solar project mitigated many environmental concerns, not everyone agrees that the university’s decision to build a utility-scale solar plant is the best choice economically. Among these critics is Frank Wolak, economics professor and director of the Program on Energy and Sustainable Development, who called Stanford’s choice “utterly uncreative.”
Understanding Wolak’s argument requires some background in energy economics and policy in the American west. Legally, the California Renewable Portfolio Standard (RPS) requires a certain percentage of electricity retail sales to come from renewable energy. California’s RPS, which will require 50 percent of energy to be renewable by 2030, is one of the most ambitious in the nation. However, California is a part of a western energy grid that spans from the border of Canada to the border of Mexico and over to parts of Wyoming, Montana, Colorado and New Mexico.
Because the direction and flow of electrons can’t be controlled, electricity on this western grid can’t be tracked from source to destination. For example, Stanford is not actually receiving the energy generated by its solar panel project directly but rather putting the energy out on the grid, to be used to meet general demand near the solar farm.
This is why the U.S. uses Renewable Energy Certificates (RECs) to track and incentivize renewable energy generation. One REC represents one megawatt-hour of renewable energy produced, roughly equivalent to the amount of electricity used by 330 homes for one hour. RECs can be bought and sold by producers and consumers separate from the actual power, providing a mechanism for electric utility companies to meet renewable portfolio standards and for individuals and businesses to lessen their environmental impact.
So in Stanford’s pursuit to lessen its environmental impact, the school isn’t actually receiving the renewable energy generated by its solar plant but rather the renewable energy certificates; this is how the school has met its 68 percent-renewables goal.
Wolak argues that instead of buying and developing a specific project and technology to earn RECs, Stanford should have simply bought more RECs from the wider western energy market. In doing so, Stanford would jumpstart the development of a west-wide REC market as well as allow “the developers and market to figure out the cheapest way to get the renewables.” Then, Wolak says, the University could have increased its renewables even more and at a cheaper price tag.
“Stanford could have gone 100 percent green,” Wolak explained. “But they wanted to do what everyone else does … This could be Stanford leading the way, but instead [they’re] following.”
There isn’t quite consensus among Stanford faculty, however. While Wolak’s alternative solution makes sense according to Dian Grueneich B.S. ’74, senior research scholar at the Precourt Institute for Energy, it does not prioritize increasing the supply of renewables.
“Stanford’s goal is [not just securing] the cheapest renewable power, but [also] being a part of a larger effort to expand how much renewable power there is,” Grueneich explained. “In California, we want to encourage additional renewable projects; we are not just interested solely in the purchase of RECs.”
RECs purchased on the market are also subject to price fluctuations. By owning the solar plant and the power it provides, Stanford pays a fixed rate for RECs for 25 years, so it may be a safer bet economically, according to Joseph Stagner, executive director of Stanford’s Department of Sustainability and Energy Management (SEM).
“Stanford decided to invest in long-term value and reliability, not play the market,” Stagner said.
Adding another factor into the picture, student group Fossil Free Stanford says that investing in long-term renewable energy solutions still does not go far enough in combating climate change.
“We’ve always supported and encouraged University efforts to make campus less carbon-intensive, but we also maintain that technological progress is not enough to ensure a livable climate in the face of the fossil fuel industry’s power,” wrote Fossil Free Stanford. “We have consistently argued that divestment is compatible with — and maximizes the broader impact of — such projects.”
At the ribbon-cutting ceremony on Dec. 2, Vice Provost John Etchemendy acknowledged that there had been many critiques of the project throughout the process.
However, the University ultimately found support from most environmental groups, including Audubon California. According to George, there’s no one perfect solution in the clean power movement. “We need anything [that] transforms the way we get energy.”
What’s important and exciting is that Stanford is taking concrete action, according to Vice President of the Stanford Energy Club Arnav Mariwala ’17, who is also a Daily staffer. “Stanford [shows] a lot of leadership when it comes to actually implementing renewable solutions and moving towards a cleaner energy future.”
Stanford will continue to move forward, according to Etchemendy. The Stanford Solar Generating Plant is significant, but not “the last piece of the puzzle,” he said. “We have other plans in store for further ways of improving the entire system and making it more sustainable.”
In his closing remarks at the ribbon-cutting ceremony, Stagner reminisced on the energy he felt as a child growing up in the Space Age — when rock songs honored satellites, The Jetsons ruled the airwaves and the impossible felt within grasp.
“The feeling I’m getting is the feeling I had as a young kid … I was really intrigued way back then about what the future could hold and what technology might bring,” Stagner said. “And so that’s the feeling I get here today when I think that Stanford University, our little city, is running off the sun.”
Contact Tia Schwab at kbschwab ‘at’ stanford.edu and Zoe Sayler at zoeneile ‘at’ stanford.edu.