Entries by Carl Berntsen

Case Study: UMass South Deerfield Pilot Project

The South Deerfield dual-use array is a research facility built at the University of Massachusetts (UMass) Crop and Animal Research and Education Farm. The pilot project is the result of a team leveraging private, public, and governmental resources. Designed and constructed in 2010 by Hyperion Systems, a solar development company based in Amherst, Massachusetts, the […]

Case Study: Joe Czajkowski Farm

The Joe Czajkowski Farm project will be a commercial agrivoltaic array in Hadley, Massachusetts, set to be completed in time for the 2023 growing season. The project was developed through a partnership with Joe and Hyperion Systems, Amherst, Massachusetts, which has a long history in agrivoltaics. The farm’s dual-use array will serve as an excellent […]

Case Study: Summit Plant Labs

Agriculture Type: Specialty greenhouse farming Project Type: Small commercial net-metering agrivoltaic system Project Size: 26.7kW-DC Project Design: Solar fence structure, SolarEdge inverters, 72-cell bifacial solar panels Location: Fort Collins, CO Developer and Contractor: Sandbox Solar Summit Plant Labs is a specialty crop farm using greenhouses and lab space to grow pristine crop starts, microgreens, and […]

Case Study: Sandbox Solar Agrivoltaics Research Site at Colorado State University’s ARDEC South

Agriculture Type: Specialty crop research farming Project Type: Small commercial net metering agrivoltaic system Project Size: 11.4kW-AC Project Design: Solar pole mount structure, SolarEdge Inverter, 72-cell bifacial solar panels, 72-cell opaque polycrystalline solar panels, thin film 40% semi-transparent solar panels Location: Fort Collins, CO Developer and Contractor: Sandbox Solar Sandbox Solar is a solar energy […]

Case Study: Grafton Solar

At Grafton Solar, cattle are grazing nearby fields of squash and lettuce at the 150-year-old family operation known as Knowlton Farms. Located in Grafton, Massachusetts, this project is demonstrating how diverse agricultural production can be maintained underneath a 2MW community solar array + 1.4MW of battery energy storage.

Water evaporation reduction by the agrivoltaic systems development

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.


Agrivoltaics is a concept in which a piece of land is simultaneously used for both energy and food production by mounting photovoltaic modules at a certain height above (or in between strips of) agricultural land. A local and system-level incorporation of water management is imperative to the sustainable implementation of agrivoltaics. Water raining on the module can be gathered and used for distinct purposes: groundwater recharge, crop irrigation, and cleaning and cooling of the PV modules. This research provides an initial overview of positive and negative impacts for each water use concept and outlines issues that should be taken into consideration and the potential for research and development. Various Managed Aquifer Recharge (MAR) technologies are a way to clean and store the water periodically in an underlying aquifer. Irrigation increases yield within the plant level and therefore increases the system’s output. Thanks to the power supply generated by the PV modules, high-tech irrigation systems can be implemented in agrivoltaic systems; the special adaption of irrigation systems to agrivoltaics poses significant potential for research and development. Meanwhile, the necessity, i.e., profitability of cleaning and/ or cooling PV modules depends on local environment and economic factors. Several cleaning techniques have been developed to mitigate soiling, ranging from manual cleaning to fully automatic cleaning systems. In agrivoltaics systems, the soiling risk can increase. Semi-automatic systems seem to have the greatest potential for agrivoltaics, because they can be used with farming equipment. Multiple cooling techniques have been developed to decrease cell temperature to increase power output, with some of them involving water. Water flowing over the module surface is a promising a promising cooling technique for agrivoltaic applications. Attaching a perforated tube to the upper edge, the entire module can be covered in a thin film of water which cools very effectively (while also cleaning the surface). A closed-circuit system could be created involving the technical components used for rainwater harvesting. The economic feasibility of cooling panels in agrivoltaic systems needs to be investigated. In certain locations, rainwater-harvesting could also be relevant for ground-mounted PV systems.

Effect of Shading on the Performance of Vitis vinif era L. cv. Cabernet Sauvignon

The effect of shading on the performance of Cabernet Sauvignon was studied. Significant different levels of canopy density were created using the growth of neighbouring vines, thus ensuring no artificial change in natural light composition. Light penetration in these canopies differed significantly between treatments. Berry mass, bunch mass and yield as well as skin colour were decreased with increasing levels of shading, while pH, K-concentration and TT A were increased. Tartaric acid decreased while malic acid increased with an increase in shading. Wine quality was negatively affected.


Genetic Algorithms-Based Optimum PV Site Selection Minimizing Visual Disturbance

In this paper, an integrated methodology is developed to determine optimum areas for Photovoltaic (PV) installations that minimize the relevant visual disturbance and satisfy spatial constraints associated with land use, as well as environmental and techno-economic siting factors. The visual disturbance due to PV installations is quantified by introducing and calculating the “Social Disturbance” (SDIS) indicator, whereas optimum locations are determined for predefined values of two siting preferences (maximum allowable PV locations—grid station distance and minimum allowable total coverage area of PV installations). Thematic maps of appropriate selected exclusion criteria are produced, followed by a cumulative weighted viewshed analysis, where the SDIS indicator is calculated. Optimum solutions are then determined by developing and employing a Genetic Algorithms (GAs) optimization process. The methodology is applied for the municipality of La Palma Del Condado in Spain for 100 different combinations of the two siting preferences. The optimization results are also employed to create a flexible and easy-to-use web-GIS application, facilitating policy-makers to choose the set of solutions that better fulfils their preferences. The GAs algorithm offers the ability to determine distinguishable, but compact, regions of optimum locations in the region, whereas the results indicate the strong dependence of the optimum areas upon the two siting preferences.

Energetic Comparison of Vertical Bifacial to Tilted Monofacial Solar

In this article, a vertical bifacial + reflector configuration is presented as a candidate for solar canals and other applications that allow dual use of the land. Modeling with weather data from Merced, CA shows output to be competitive with fixed 20° tilt systems, with south-facing vertical orientation showing 117% and 87% of annual output of south-facing 20° systems with and without a reflector, respectively. Repetition with weather data from Houston, Denver, and Miami produces similar results, with values ranging from 112%–121% and 82%–94%, which serve as conservative estimates due to lack of modeled soiling on tilted systems in the latter comparison. South-facing vertical orientations have better performance in nonsummer months relative to other systems, resulting in a flatter seasonal curve, with useful implications for load balancing and energy storage. East- and west-facing vertical orientations outperform their fixed tilt defaults, even without a reflector, and tolerate higher dc/ac inverter ratios than similar south-facing vertical orientations before appreciable clipping effects are seen.