By Jordan Thompson • jmt185@pitt.edu
The Biden administration and various states have set a goal of net-zero emissions by 2050. However, to do this the United States will have to drastically increase renewable energy output from its 2021 level of 12% of total US energy consumption.
Solar energy will play a key role in increasing renewable energy consumption, as according to the Department of Energy’s Solar Futures Study, “it is possible to envision—and chart a path toward—a future where solar provides 40% of the nation’s electricity by 2035.” A lot of land will be required for such an endeavor though, with the Solar Futures Study estimating that 0.5% of land in the contiguous United States will have to be used for solar to reach 2050 emissions reduction goals. For context, the Solar Futures Study estimates agriculture represents 43% of the contiguous United States’ surface area.
The idea of covering more land with solar panels unnerves many Americans, especially those with farms. Recently, the residents of Pilesgrove Township, a Salem County farming community, voiced their displeasure to the township’s planning board about Dakota Power Partners (DPP) building an 800-acre, 150 MW solar farm in their town. Despite protests from residents, who were unhappy with solar panels being placed on fertile farming land, the project was approved by the town’s planning board, with construction ending and operations expected to start during 2023.
However, solar arrays and agriculture can coexist in a symbiotic relationship known as agrivoltaics. With agrivoltaics, solar panels are placed above crops or pasture, and the results are proving to be beneficial. Although plants rely on sunlight, they all have a saturation point, and once that is reached, any light beyond that point doesn’t increase photosynthesis and only increases the plant’s need for water. Therefore, plants grown under a solar panel’s shade are protected from the sun’s ultraviolet rays, which helps reduce air temperature and water evaporation. A study from the US Department of Energy’s National Renewable Energy Laboratory (NREL) has shown that water-use efficiency for the jalapeno and cherry tomato were 157% and 65% greater, respectively, in an agrivoltaic system.
Agrivoltaics also increases the solar panel’s energy capacity. Since plants retain more water in the agrivoltaic system, they give off water vapor that helps cool the photovoltaic panels from below, increasing panel efficiency by as much as 10%, according to a study from Oregon State University. The NREL study mentioned above also found that agrivoltaic panels were approximately 9% cooler during daytime hours than rooftop panel arrays, allowing for better performance.
The benefits of agrivoltaics also include the diversification of farm income, something that NJ farmers are beginning to discover. Small farms can earn thousands of dollars per acre every year by leasing land to solar companies. And farms with livestock can go the route of “solar grazing,” the practice of installing solar panels over grazing land for animals.
One New Jerseyan utilizing solar grazing is Julie Bishop. In recent years she struck a deal with a solar company to graze her sheep on their 15 acres of land. The deal allows the solar company to generate renewable energy while Bishop gets paid to have her sheep essentially cut the company’s grass. Bishop has since renamed her farming operation “Solar Sheep” and now has flocks of sheep at multiple solar sites around New Jersey. “It all started because I had a herding dog and I wanted sheep. And then I ended up with more sheep than I could handle, so I was looking for pasture area,” Bishop, explained in an interview with Farm Credit, which financed her barn expansion.
Bishop has also contracted to have her sheep graze at the DPP solar farm, Nichomus Run, in Pilesgrove, and this will be the first designed specifically for her sheep to graze. There is the potential for problems if sheep are turned loose in an electrical installation that is not designed to accommodate them. DPP is even including a barn for Bishop to use.
The success and benefits of agrivoltaics have not gone unnoticed by the New Jersey officials, who have set an ambitious goal of 100% renewable energy by 2050. In June 2021, the New Jersey Legislature passed the Dual-use Solar Act, establishing the Dual-Use Solar Energy Pilot Program for farmland. The pilot program will allow a small number of farmers to install agrivoltaic systems while the technology is being researched and developed. This year’s state budget even allocated $2 million to the New Jersey Agricultural Experiment Station for installing photovoltaic panels on its research farms.
The federal government has followed suit, and on May 5, 2022, the US Department of Energy Solar Technologies Office announced the Foundational Agrivoltaic Research for Megawatt Scale funding opportunity. This will award $8 million in funding for projects that examine how agrivoltaics can provide new economic opportunities and possibilities to farmers, rural communities, and the solar industry.
Agrivoltaics, including solar grazing, have shown to increase land-use efficiency while also benefitting energy and food production. Renewable energy has often been seen at odds with agriculture but recent research projects and experiments demonstrate that combining the two industries is worthwhile for both. Farms have been able to diversify their income, strengthen their yields, and reduce their carbon footprint by transitioning to renewable energy.
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