Tag Archive for: AgriSolar

The triple benefits of the AgriVoltaic Systems Development (AVSD) have been well demonstrated, not only for the PV electricity generation but also for reduced water evaporation, enhancing further the benefits of simultaneously crop growth on the same land area. However, the reduction rate of the water evaporation of AVSD has not been investigated in a quantitative way. Therefore, this study conducted experiments to measure water evaporation reduction under the Concentrated-lighting Agrivoltaic System (CAS) and the Even-lighting Agrivoltaic System (EAS). Evaporation containers and pans were placed in the bare soil (CK) under the CAS and the EAS. Our results showed a significant reduction in water evaporation under CAS and EAS. Cumulative soil surface evaporation of CK, CAS, and EAS for 45 days was 80.53 mm, 63.38 mm, and 54.14 mm. The cumulative water evaporation from soil and pan surfaces decreased by 21 % and 14 % (under CAS), 33 %, and 19 % (under EAS), respectively. The slope β1 ∕= 0 of simple linear regression showed a significant positive relationship between evaporation time and cumulative water evaporation. The correlation coefficient in all treatments was more than 0.91, suggesting a robust linear relationship. The feasibility of AVSD could significantly reduce irrigation water, enhance crop growth, and generate electricity simultaneously on the same agricultural land.

Australian Researchers Develop Solar Panels Optimized for Agrisolar  

“University of New South Wales researchers have teamed up with Tindo Solar to develop a line of semi-transparent modules, specialized for agrivoltaic cropping, which will use nanoparticles tuned to capture different parts of the light spectrum. ‘There is evidence you don’t need the full spectrum and some plants will work even better if you provide them with only part of the spectrum,’ project lead and UNSW Associate Professor Ziv Hameiri tells PV Magazine Australia. Crucially, he says, the project will also open a line between farmers, solar researchers and industry, creating the potential for mutual benefits.”  – PV Magazine 

Agrisolar Operations Show That Solar Does Not Compete with Farmland 

“In short, Agrivoltaics is a rapidly growing branch of the energy transition. It is being applied to all manner of crops across the world. All kinds of benefits are emerging, with China even using it to reverse desertification. Not only is it expanding clean energy production, it is providing a vital second income stream for farmers. Banning it would cut off a really important opportunity for Britain’s farmers, at a time when rural poverty is a real issue.” – Green Peace 

Oregon State Develops 5-Acre Agrisolar Project 

“Oregon State University has started construction on a $1.5 million research project to optimize dual-use, co-developed land hosting solar photovoltaic arrays 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. The 326-kW project is the result of a partnership between Oregon State and the Oregon Clean Power Cooperative, which developed the solar array and financed the construction of the solar array.” – Solar Power World 

This article offers practical advice for agrivoltaic systems on how to implement an agricultural area under ground-mounted photovoltaic-power systems without agricultural “pre-plans.” These systems are useful for policy making and optimizing land use efficiency in terms of energy production, food supply, environmental impact, local economy, and sustainable societies.

Dr. John Walker (TAMU AgriLife Research) and Haley Gosnell (who runs joined us to discuss the extensive practical targeted grazing knowledge he and his team have collected from graziers across the U.S. and Canada. John is a range livestock and wildlife specialist who focuses on vegetation and diet selection for grazing ruminants.

From 2021-2022, he and his team conducted a survey of over a 100 targeted grazing serviced providers in the U.S. and Canada, as well as parallel focus groups, on lessons learned from their experiences with targeted grazing. The survey covered a number of different landscapes (from rural to urban and private to public) and variations in vegetation, grazing scales (small to large), and grazing season lengths. This was part of an effort to update the American Sheep Industry’s 2006 Targeted Grazing Handbook.

John discussed the results of the survey and its insights into targeted grazing.

Hosts: Kevin Richardson (ASGA), Caroline Owens (ASGA Board Member), and Carl Berntsen from AgriSolar Clearinghouse / NCAT

This Teatime is part of a series co-hosted and sponsored by the AgriSolar Clearing House team. We thank them for their generous support and for adding their expertise to the Teatime events!

About the Speakers:

Dr. John Walker, Professor, Range Specialist: I am a Professor and Resident Director of Research at the Texas A&M AgriLife Research & Extension Center in San Angelo, Texas. My responsibilities include providing leadership to a multi-disciplinary team of six scientists that develop new technologies for increasing the efficiency and sustainability of range livestock and wildlife production. My research interest relates to developing new technologies for modifying diet selection of grazing ruminants. It has long been known that livestock grazing affects the botanical composition of vegetation communities. By avoiding some plant species and preferring others, livestock provide a competitive advantage to plants that are avoided, which allows them to increase and often dominate a site. Grazing systems were developed to help overcome this adverse effect of selective grazing on rangeland composition. I am interested in directly modifying the grazing habits of livestock through selective breeding, nutritional interventions and learning. In conjunction with this research, I have developed near-infrared spectroscopy calibrations that use fecal spectra to predict the botanical composition of diets.

This guide provides an overview of the federal investment tax credit for residential solar photovoltaics (PV). The federal residential solar energy credit is a tax credit that can be
claimed on federal income taxes for a percentage of the cost of a solar PV system paid for by the taxpayer.

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.

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.

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 

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.

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 

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.