Japan would like to increase the amount of electricity it gets from renewable sources. According to the Institute for Sustainable Energy Policies in Tokyo, it is planning for up to 38% of its electrical energy to come from renewable sources by 2030, but solar power accounted for only 8.9% of the country’s energy mix as of 2020. That needs to double if it is to reach its energy goals.
Japan has many mountainous areas that are unsuitable for solar panels. One potential solution is referred to as solar sharing — using land for both farming and solar power at the same time. One of the leading proponents of solar sharing is Germany’s Fraunhofer ISE. The idea is simplicity itself. Mount solar panels high enough above the ground to permit plants to grow and farming equipment to operate underneath them.
According to Yahoo Finance, Takeshi Magami has a one hectare (2.5 acre) farm east of Tokyo. Like many of his colleagues, he grows potatoes, ginger, and eggplants. Unlike many of those same colleagues, most of his arable land is covered by solar panels — 2,826 of them. They supply nearly all the power needed to run the farm, where all the machinery except the tractor and a hand tiller are electric.
The surplus solar power from the panels is fed back to the utility grid and earns him 24 million yen ($187,000) of additional revenue a year. That’s eight times more than the 3 million yen ($23,500) he earns from the crops he grows. Although Japan has recently reduced the financial benefits available for selling power to the utility grid, Magami still makes more from his solar panels than from growing crops.
“Our goal is to electrify and automate all steps of farming” and create a model for what sustainable agriculture could look like, says Magami, who runs his farm as part of his start-up company, Chiba Ecological Energy Inc.
The solar sharing movement is gaining adherents as the global push to replace fossil fuels encourages more innovative approaches to generating more renewable energy and reduce their exposure to foreign energy suppliers. Solar sharing is also useful in countries with harsh growing environments, protecting crops by absorbing sunlight and acting as a shield. Panels mounted higher off the ground also stay cooler, which increases their efficiency.
“We’ve seen many regions with climate change, and agrivoltaics could mitigate and make agriculture more resilient,” said Max Trommsdorff, head of the agrivoltaics group at the Fraunhofer ISE in Germany. “Small countries in the sun belt with high population are where agrivoltaics are the most urgent and promising.”
Japan, which is targeting to go carbon neutral by 2050, has limited capabilities for solar power because of its mountainous terrain. To compensate, the government is looking toward rooftops, railway lines, highways, and airports, as well as its limited agricultural land.
While Magami has demonstrated the success of solar sharing, the practice hasn’t been widely adopted in Japan, where agrivoltaics is a tough sell for Japan’s elderly farming population. Many are without successors to take over the business and they’re unwilling to make the heavy investment in solar panels that may take decades to pay off. It also can be a distraction from the business of growing crops.
“Some people are against it as it ruins aesthetics, or for getting in the way of farm work,” said Chiho Egashira, an official at Japan’s ministry of agriculture. It can be cumbersome for farm equipment to dodge poles that lift the panels off the ground. While solar panels can be an alluring prospect for extra income, the ministry wants to ensure food security remains the priority. And so it has put in place rules to ensure production levels.
Magami says that despite the hurdles, it’s necessary for the country to embrace agrivoltaics to reach carbon neutrality by 2050. He calculates that using solar panels on roughly 5% of Japan’s arable farmland — about 200,000 hectares — could generate 20% of the country’s electricity. “Things like geothermal and hydropower take decades to start operating,” Magami says. “We’re no longer in an era where the best way is to find unused plots of land available and install it with panels. Those have all been filled.”
Other nations are making progress with solar sharing, especially in countries that face a similar lack of space. South Korea has targeted 10 gigawatts of agrivoltaics capacity by 2030 under its Renewable Energy 2030 plan. Taiwan is eyeing the scheme as it seeks available spaces for renewable installation, according to Magami. Italy plans to invest 1.1 billion euros ($1.2 billion) in agrivoltaics to create about 2 gigawatts of capacity.
China, the world’s top solar panel producer, is home to the largest agrivoltaic system, a project covering 20 million square meters (20,000 hectares) of land in the desert in Ningxia. Of the 2.8 gigawatts of agrivoltaic systems installed globally, China had roughly 1.9 gigawatts of capacity as of 2020, according to the Fraunhofer Institute.
Adoption in the US varies, with more progressive states in the Northeast launching projects with government funding, according to Mark Uchanski, an associate professor at Colorado State University who specializes in sustainable and organic agriculture. “People’s appetites are increasing,” he said. Agrivoltaics “is a perfect storm for wanting food security, energy, and working toward emission goals,” he said.
Combining solar power with agriculture is not appropriate for all crops. Not everything grows well in shade, although experiments show a surprising number of fruits and vegetables do. It even works well for shrimp and fish farms. Local laws and tariffs can also make a significant difference in whether constructing solar power facilities is economically viable.
For farmers who are burdened with increasing costs for taxes, seeds, fertilizer, and equipment purchases, the ability to generate additional income from their land has to be a powerful incentive to consider agrivoltaics. Many in the agricultural community look askance at solar sharing, saying putting up solar panels is not real farming and destroys the bucolic nature of rural areas. Then again, phone poles, cell phone towers, and the aroma of factory-scale pig farms don’t do much to improve the quality of life in those areas either.
One way to reduce carbon emissions is to simply stop burning coal, oil, and methane to make electricity. Agrivoltaics may be a more realistic solution that increases energy security for the community while bolstering the income of farmers. It’s not the only answer, but it should be one of the options for preserving the Earth for future generations.
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