Tag Archive for: AgriSolar

Case Study: ENEL Green Power’s Lake Pulaski

Lake Pulaski is an agrivoltaic solar power plant site developed by Enel Green Power that spans over 68.2 acres in Buffalo, Minnesota. This site is one of 16 developed for the Aurora Distributed Solar LLC project in 2017, supporting pollinators, grazing, and an apiary. The layout consists of 34,668 panels at 315 watts each, spanning over 500 individual arrays. The total plant system size is 10.92MW (dc). Each panel has a SolTech single, horizontal axis tracker to follow the sun path and optimize production. This tracker was chosen over the more standard axis-pole trackers due to their ability to allow curves in the array installation to accommodate the rolling landscape. The developers strived to install the system with minimal land disturbance to maintain the landscape and reduce excavation, thus allowing the panels to move with the rolling hills. Panel height was design to be approximately 2.5 fee from the ground at the maximum tilt angle of 45o to allow grazing sheep to pass under without harm to sheep or panels. This sets the total height of each array at a maximum of 10 feet.

Showing how the panel height is appropriate to allow for sheep to graze under panels.
Solar tracking system with grazing sheep

The landscape is grazed once a year near the end of September for one month to reduce the need for mowing, save on labor and gas, and maintain a healthy soil chemistry. Graduate students at Temple University in Pennsylvania are conducting studies on the benefits of grazing, such as soil composition, a reduced mowing, and a reduction in spraying for weeds. Eight of the 16 Aurora project sites are grazed for research purposes. Occasional mowing is required if the area has a high-growth year. Minnesota Native Landscapes (MNL) developed the original native seed profile to help promote pollinator activity under the panels. The final seeding was completed by Westwood Professional Services. MNL also maintains the pollinator and native landscape. Bare-grounded spraying is used to kill off unwanted invasive species, such as thistle. These areas are then fenced off to prevent wildlife and sheep in the area. Soil samples are taken from sprayed and mowed areas for research. Lake Pulaski also promotes the bee population by allowing bee farmers to move their hives next to the site to help pollinate the area and grow healthier bees.

Lake Pulaski Native Landscape
Lake Pulaski Native Plant
Dustin Vanesse from Bare Honey holds up a hive panel covered in honey bees.

Lake Pulaski is not without maintenance needs. The enormity and complexity of the site requires technicians, plant experts, landscapers, and sheep farmers to ensure that the site function as designed. Enel Green Power does most of the technical maintenance, while MNL sprays and maintains the plants. The SolTech trackers require slightly more maintenance than pole trackers, and they can go offline due to storms, sheep knocking the sensors, and other natural causes. Background research is being conducted by ENEL to determine whether the tracking system is worth the extra maintenance. At the end of the site’s service life, which is typically 25 years, the developers hope to decommission the system and return the land to agriculture with richer soil than the gravel alternative and unharmed adjacent landscapes. The research from this site will help quantify the benefits that agrivoltaics can bring to both solar development and agriculture industries.

AgriSolar News Roundup: Solar and Taxes in NC, Dutch Agrisolar Research, Agrivoltaics in Maine  

Solar Projects Increase Tax Revenue in North Carolina 

“Proposed large-scale solar facilities continue to draw opposition in North Carolina from critics who argue that swaths of panels are blights on the landscape and threaten farms in a state where agriculture is the leading industry. But those facilities have become a financial boon to local communities, particularly in rural areas with limited sources of tax revenue, a newly released study from the N.C. Sustainable Energy Association found.” – Greensboro 

Dutch Research Studies Agrisolar  

“During a four-year pilot project, Dutch independent research organization TNO, in collaboration with Vattenfall and Aeres University of Applied Sciences (UAS), is developing a sun-tracking algorithm that monitors various factors, such as crop yield, energy yield and the effects of herb strips, weather forecast, energy price and soil condition.” – Vattenfall 

Small Farms in Maine are Good Candidate for Agrivoltaics 

“Maine’s prevalence of small farms with low-lying, hand-harvested crops makes the state a good candidate for blending solar energy and food production on the same land, but farmers may not take the risk without funding for pilot projects. 

Maine may be uniquely positioned for this emerging field, known as agrivoltaics or dual-use solar. Nationally, most successful projects so far have involved extras like solar grazing or pollinator habitat alongside panels at small farms with low-lying, hand-harvested crops — precisely the type of farms that dominate much of Maine’s agricultural sector.” – Energy News 

Photovoltaic Stormwater Management Research and Testing (PV-SMaRT) Potential Stormwater Barriers and Opportunities

In this document, the Great Plains Institute (GPI) identified existing permitting practices and standards for solar development in the five PV-SMaRT case study states (New York, Georgia, Minnesota, Colorado, and Oregon) and other states across the nation. GPI then completed a “barriers and opportunities” assessment of existing practices to identify opportunities for reducing solar development soft costs and compliance costs, while maintaining or improving water quality outcomes.

PV-SMaRT-Potential-Stormwater-Barriers-and-OpportunitiesDownload

AgriSolar News Roundup: The Power of Shade, Oregon Agrivoltaics Development, Agrivoltaics is a “Win-Win”  

The Power of Shade in Agrivoltaics 

“The sun’s energy feeds grazing fodder and crops side-by-side with solar panels. ‘For farmers, it’s a two-income stream,’ said Brad Heins, professor of animal science at the University of Minnesota. That might mean planting crops that thrive in the shade cast by the panels. Or, in Heins’ case, it can mean cooling cows in the panels’ shade rather than resorting to expensive fans in a barn. 

Heins and his colleagues are at the cutting edge of this new field (agrivoltaics), but they aren’t alone. There are hundreds of agrivoltaics projects underway in the US. Some work better than others, and some may wind up not working at all. But the best will lead to a greener and more profitable rural America that embraces renewable energy as an asset.” – The Washington Post 

Agrivoltaic Site Under Construction in Oregon 

“Construction is underway on a $1.5 million project that will allow Oregon State University researchers to further optimize agrivoltaic systems that involve co-developing land for both solar photovoltaic power and agriculture. The five-acre Solar Harvest project is located at Oregon State’s North Willamette Research and Extension Center in Aurora, Oregon, 20 miles south of Portland. It is the result of a partnership between Oregon State and the Oregon Clean Power Cooperative. 

The problem with agrivoltaics research to date, Higgins said, is that it has occurred using solar arrays designed strictly for electricity generation rather than in combination with agricultural uses, such as growing crops or grazing animals. The solar array at the North Willamette Research and Extension Center is designed specifically for agrivoltaics research, with panels that are more spread out and able to rotate to a near vertical position to allow farm equipment to pass through, Higgins said.” – Oregon State University 

Agrivoltaics is Shown to be a “Win-Win” for Food and Energy 

“’With the right investment, innovation and robust collaboration, agrifood systems could become one of the world’s most hopeful solutions to climate change, as well as reduce poverty and provide nourishment for all,’ says Sean de Cleene, head of the Food Systems Initiative at the World Economic Forum (WEF). 

‘The hallmark characteristic of agrivoltaics is the sharing of sunlight between the two energy conversion systems: photovoltaics and photosynthesis,’ says Jordan Macknick, lead energy-water-land analyst at the US National Renewable Energy Laboratory. ‘It essentially mimics what humans have been doing for hundreds of years with agroforestry – think shade-grown coffee – intentionally creating partial shade to create multiple layers of agricultural productivity on the same piece of land.’” – Energy Monitor 

Photovoltaic Storm Water Management Research and Testing: Barriers and Best Practices

This resource is an overview of the Photovoltaic Storm Water Management Research and Testing (PV-SMaRT) project, which seeks to develop and disseminate research-based, solar-specific resources for estimating storm water runoff at ground-mounted PV facilities as well as storm water management and water quality permitting best practices.

PV-SMaRT-Barriers-and-Best-PracticesDownload

AgriSolar News Roundup: Agrisolar in the Midwest, Community Solar in California, Achieving Zero-Carbon Goals  

Solar Power and Crops Grow Together in the Midwest 

“Farmland is well suited for solar development of all kinds, for the same reasons it’s good for growing crops — it’s largely flat, drains well and gets lots of sun. Grazing land for animals like sheep can also be a good fit for solar. But what makes these Purdue research panels different is that they haven’t taken farmland out of production — they’re built over top of the corn itself.   

Researchers want to see how the co-location strategy could be a salve to a growing strain between solar and farming in the Corn Belt — where residents and towns are pushing back on what they see as industrialization in rural communities. That includes communities in Wisconsin, where University of Wisconsin-Madison researchers are working with Alliant Energy to pursue similar research on university-owned land near Stoughton.” – The Journal Times 

Renters in California Will Have Access to Community Solar 

“Following Governor Gavin Newsom’s signature, California passed AB 2316, the Community Renewable Energy Act. The law creates a community renewable energy program, including community solar-plus-storage, to overcome access barriers for nearly half of Californians who rent or have low incomes. 

A new market for residents to opt into renewable energy contracts opens in California following Gavin Newsom’s signature on the Community Renewable Energy Act. The law will now be evaluated and implemented by the California Public Utilities Commission.” – PV Magazine 

Roughly 26 Million Acres Needed to Reach Zero-Carbon Goals 

“By dedicating about 1% of the country’s land to solar energy—an area roughly the size of Kentucky—we could enable the nation to power itself with zero carbon emissions. Assuming fossil fuel and biomass energy would be replaced with green energy, it would take approximately 13 million acres of land to power today’s grid solely from solar facilities. It should be noted, however, that this amount would likely need to double to account for energy storage, electric vehicle (EV) charging stations, and the necessary increase in electrical infrastructure. But by dedicating about 26 million acres or 1% of the country’s land to solar energy—an area roughly the size of Kentucky—we could enable the nation to power itself with no carbon emissions.” – PV Magazine 

AgriSolar News Roundup: Agrisolar Refrigeration, Pennsylvania Agrisolar, New Zealand Agrisolar Development  

African Company Provides Agrisolar Refrigeration 

“A company called AkoFresh is providing solar-powered refrigerated storage that it says extends the shelf life of perishable crops from about 5 days to 21 days. This will boost seasonal income for farmers by more than $10 million, as well as reduce greenhouse gas emissions by 15%. Farmers can rent a space in the cold store for a daily fee of $0.30 per 20-kilogram crate of produce or take up a weekly subscription. They can also pay for the cold storage with crops instead of cash.” – World Economic Forum 

Research Being Conducted at Pennsylvania Agrisolar Site 

“In recent years, the environmental management of solar farms has become an exciting area of academic research, to assess how different practices affect the productivity of solar and agricultural enterprises and the land on which they operate. Two studies seeking to answer research questions around these topics are currently underway at Lightsource bp’s Nittany 1, 2 and 3 solar projects in Pennsylvania.   

All three sites were designed and are being actively managed to boost biodiversity and support pollinator populations, in addition to generating clean energy for Penn State and their students. Lightsource bp seeded the sites with a mix specifically formulated by the American Solar Grazing Association (ASGA), in partnership with Ernst Conservation Seeds and Pollinator Service. The seed mix, aptly named ‘Fuzz and Buzz,’ was designed to support pollinator species at solar sites, in addition to flocks of sheep. At Nittany 1, more than 700 sheep are managing vegetation through rotational grazing, an example of agrivoltaics, or co-located solar and agriculture.” – Lightsourcebp 

 New Zealand Solar Farm Will Host Sheep 

“Harmony Energy New Zealand has been granted approval to develop a solar farm in the Waikato which will generate electricity to power 30,000 homes as sheep graze underneath. The Environmental Protection Authority (EPA) has approved Harmony’s proposal for approximately 330,000 solar panels to be installed on 182 hectares of a 260-hectare site at Te Aroha West. The land will remain in the ownership of Tauhei Farms Limited, with livestock grazing continuing with sheep, rather than the current dairy herd.” –https://www.stuff.co.nz/business/300693453/hauraki-solar-farm-that-could-power-30000-homes-gets-green-light Power Technology 

ASGA + AgriSolar Clearinghouse September Teatime: Vegetation Management at Operating Solar Sites with Keanen Ryan and Lexie Hain, Lightsource bp

What are asset managers looking for when they evaluate proposals from solar graziers? What kinds of concerns do asset managers have about grazing that need to be resolved to get to the contract stage?

Keanen Ryan and Lexie Hain from Lightsource bp joined us for a wonderful conversation that answered these questions from the solar operations perspective. Keanen and Lexie also discussed what they’re looking for from graziers in terms of services and experience in order to meet the economic and sustainability standards of Lightsource bp.

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Agrivoltaic Engineering and Layout Optimization Approaches
in the Transition to Renewable Energy Technologies: A Review

This resource shows that agrivoltaics have the potential to benefit both crop yield and photovoltaic efficiencies. Innovative engineering technologies related to photovoltaic tracking along with new generation photovoltaic cells were reviewed to determine the factors that influence optimization in agrivoltaic systems. The review also investigates the last five years of research in agrivoltaic optimization and implications of future AV developments.

challenges-13-00043-v2Download

AgriSolar News Roundup: Vermont Agrisolar Study, Agrisolar Research in Maine, Wisconsin Dairy Farm Goes Agrisolar 

Vermont Agrisolar Study Shows that Saffron Grows Well Under Solar Panels 

“A study released earlier this year summarized the results of a three-year experiment conducted by the University of Vermont. The research concluded that, given the right soil conditions, saffron grows well in the aisles and at the edges of a solar array, which could boost bottom lines for farmers by allowing them to draw dual revenue streams from a single section of land. 

‘We could see diversified vegetable growers growing lots of spinach and kale, but they weren’t making any money at it because everybody was growing the same thing. We felt saffron offered an opportunity for these growers to add a high-value crop,’ said Margaret Skinner, a researcher at the University of Vermont.  

According to the study, “when soil conditions are suitable, saffron can be grown successfully within a conventional tilted solar array, generating between $7,500 – 130,000 per acre.” – Energy News Network 

University of Maine Studies Agrisolar Blueberry Yield  

“A farmer in Maine has teamed up with a solar developer and university researchers to find out how his (blue)berries fare when partially shaded by solar panels. The University of Maine is studying this example of dual-use agrivoltaics.  

The solar installation was developed by the Boston-based solar developer BlueWave, and it is owned by the company Navisun, which makes lease payments to the landowner. Sweetland tends, harvests, and sells the blueberries, and shares profits with the landowner. 

The university (Maine) received grant funding to continue the study for three more years from the Northeast Sustainable Agriculture Research Education program, which is supported by the U.S. Department of Agriculture’s National Institute of Food and Agriculture. The research team will compare the blueberry yield among the plants fully shaded by panels, plants partially shaded by panels and plants with full sun. The panels are 8 feet tall in rows spaced 8 feet apart.” – Canary Media 

 Wisconsin Dairy Farmer Finds Financial Safety in Agrisolar  

“Brent Sinkula, president of the Manitowoc County Farm Bureau, understands the challenges Wisconsin dairies are facing. The changing dairy market has made it more difficult for small and mid-sized farms to continue. Without plans to expand the dairy, Sinkula was looking for another way to maintain the family farm. In 2018, an energy company approached him interested in renting 500 acres, about a third of his land, to install solar energy panels.  

For Sinkula, hosting solar panels on his land provides a financial safety net for the farm. He’s not the only farmer to make similar arrangements. Farmers have what solar energy companies need: land. Across the state, partnerships between dairy farms and energy companies are increasing, changing the landscape and providing farmers extra revenue in a sometimes unpredictable market.” – WPR