@article{ravishankar_esh_rozenstein_vitoshkin_kribus_mittelman_jakhar_hernandez_2023, title={Improved Land Use Efficiency Through Spectral Beam Splitting in Agrivoltaic Farms}, volume={2}, ISBN={["*****************"]}, DOI={10.52825/agripv.v2i.997}, abstractNote={Installing photovoltaic (PV) collectors above arable land (Agrivoltaics) can aid with the shortage of available land area for solar power generation and food production. Most open field agrivoltaics are based on opaque PV devices which absorb photosynthetically active radiation (PAR, 400-700 nm), reducing crop yield and increasing variability in light distribution across the field. This research evaluates the performance of spectral beam splitter integrated photovoltaic (BSIPV) modules using a PV performance model. A high percentage (66 %) of PAR incident on the spectral beam splitter is transmitted effectively to the plants, while the near infrared radiation (NIR, > 700 nm) is reflected to the adjacent bifacial opaque photovoltaic module to generate power. In the model, seven rows of modules were placed uniformly across the field at a height of four meters from the ground. Considering a cool season (November – March) in Yuma, Arizona, in a conventional opaque PV agrivoltaic farm received 43 % lower total daylight integral (TDLI) across the season in comparison to open field with a coefficient of variation (ratio of standard deviation to mean expressed in percentage) of 56 % in TDLI across the field. On the other hand, the BSIPV agrivoltaic farm limited the drop in TDLI to 7 % in comparison to open field and the coefficient of variation to 14 % across the field. Thus, BSIPV showed a 36 % improvement in TDLI relative to the conventional opaque PV agrivoltaic farm. The results of the current study justify further research on the proposed collector concept.}, journal={AGRIVOLTAICS WORLD CONFERENCE 2023}, author={Ravishankar, Eshwar and Esh, Shir and Rozenstein, Offer and Vitoshkin, Helena and Kribus, Abraham and Mittelman, Gur and Jakhar, Sanjeev and Hernandez, Ricardo}, year={2023} } @article{charles_edwards_ravishankar_calero_henry_rech_saravitz_you_ade_o'connor_et al._2023, title={Emergent molecular traits of lettuce and tomato grown under wavelength-selective solar cells}, volume={14}, ISSN={["1664-462X"]}, DOI={10.3389/fpls.2023.1087707}, abstractNote={The integration of semi-transparent organic solar cells (ST-OSCs) in greenhouses offers new agrivoltaic opportunities to meet the growing demands for sustainable food production. The tailored absorption/transmission spectra of ST-OSCs impacts the power generated as well as crop growth, development and responses to the biotic and abiotic environments. To characterize crop responses to ST-OSCs, we grew lettuce and tomato, traditional greenhouse crops, under three ST-OSC filters that create different light spectra. Lettuce yield and early tomato development are not negatively affected by the modified light environment. Our genomic analysis reveals that lettuce production exhibits beneficial traits involving nutrient content and nitrogen utilization while select ST-OSCs impact regulation of flowering initiation in tomato. These results suggest that ST-OSCs integrated into greenhouses are not only a promising technology for energy-neutral, sustainable and climate-change protected crop production, but can deliver benefits beyond energy considerations.}, journal={FRONTIERS IN PLANT SCIENCE}, author={Charles, Melodi and Edwards, Brianne and Ravishankar, Eshwar and Calero, John and Henry, Reece and Rech, Jeromy and Saravitz, Carole and You, Wei and Ade, Harald and O'Connor, Brendan and et al.}, year={2023}, month={Feb} } @article{ravishankar_booth_hollingsworth_ade_sederoff_decarolis_brendan t. o'connor_2022, title={Organic solar powered greenhouse performance optimization and global economic opportunity}, volume={15}, ISSN={["1754-5706"]}, url={https://doi.org/10.1039/D1EE03474J}, DOI={10.1039/d1ee03474j}, abstractNote={This work integrates greenhouse energy demand, solar power production, and plant growth modeling to assess the economic opportunity of organic solar powered greenhouses. Results show these systems have positive economic outlook across broad climates.}, number={4}, journal={ENERGY & ENVIRONMENTAL SCIENCE}, publisher={Royal Society of Chemistry (RSC)}, author={Ravishankar, Eshwar and Booth, Ronald E. and Hollingsworth, Joseph A. and Ade, Harald and Sederoff, Heike and DeCarolis, Joseph F. and Brendan T. O'Connor}, year={2022}, month={Mar} } @article{ravishankar_charles_xiong_henry_swift_rech_calero_cho_booth_kim_et al._2021, title={Balancing crop production and energy harvesting in organic solar-powered greenhouses}, volume={2}, ISSN={["2666-3864"]}, DOI={10.1016/j.xcrp.2021.100381}, abstractNote={Adding semitransparent organic solar cells (ST-OSCs) to a greenhouse structure enables simultaneous plant cultivation and electricity generation, thereby reducing the greenhouse energy demand. However, there is a need to establish the impact of such systems on plant growth and indoor climate and to optimize system tradeoffs. In this work, we consider plant growth under OSCs and system-relevant design. We evaluate the growth of red leaf lettuce under ST-OSC filters and compare the impact of three different OSC active layers that have unique transmittance. We find no significant differences in the fresh weight and chlorophyll content of the lettuce grown under these OSC filters. In addition, OSCs provide an opportunity for further light and thermal management of the greenhouse through device design and optical coatings. The OSCs can thus affect plant growth, power generation, and thermal load of the greenhouse, and this design trade space is reviewed and exemplified.}, number={3}, journal={CELL REPORTS PHYSICAL SCIENCE}, publisher={Elsevier BV}, author={Ravishankar, Eshwar and Charles, Melodi and Xiong, Yuan and Henry, Reece and Swift, Jennifer and Rech, Jeromy and Calero, John and Cho, Sam and Booth, Ronald E. and Kim, Taesoo and et al.}, year={2021}, month={Mar} } @article{ravishankar_booth_saravitz_sederoff_ade_brendan t. o'connor_2020, title={Achieving Net Zero Energy Greenhouses by Integrating Semitransparent Organic Solar Cells}, volume={4}, ISSN={["2542-4351"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-85079138223&partnerID=MN8TOARS}, DOI={10.1016/j.joule.2019.12.018}, abstractNote={Greenhouses vastly increase agricultural land-use efficiency. However, they also consume significantly more energy than conventional farming due in part to conditioning the greenhouse space. One way to mitigate the increase in energy consumption is to integrate solar modules onto the greenhouse structure. Semitransparent organic solar cells (OSCs) are particularly attractive given that their spectral absorption can be tuned to minimize the attenuation of sunlight over the plants photosynthetically active spectrum. Here, the benefits of integrating OSCs on the net energy demand of greenhouses within the U.S. are determined through a detailed energy balance model. We find that these systems can have an annual surplus of energy in warm and moderate climates. Furthermore, we show that sunlight reduction entering the greenhouse can be minimized with appropriate design. These results demonstrate that OSCs are an excellent candidate for implementing in greenhouses and provide an opportunity to diversify sustainable energy generation technology.}, number={2}, journal={JOULE}, author={Ravishankar, Eshwar and Booth, Ronald E. and Saravitz, Carole and Sederoff, Heike and Ade, Harald W. and Brendan T. O'Connor}, year={2020}, month={Feb}, pages={490–506} } @article{hollingsworth_ravishankar_o'connor_johnson_decarolis_2020, title={Environmental and economic impacts of solar-powered integrated greenhouses}, volume={24}, ISSN={["1530-9290"]}, DOI={10.1111/jiec.12934}, abstractNote={AbstractGreenhouse vegetable production plays a vital role in providing year‐round fresh vegetables to global markets, achieving higher yields, and using less water than open‐field systems, but at the expense of increased energy demand. This study examines the life cycle environmental and economic impacts of integrating semitransparent organic photovoltaics (OPVs) into greenhouse designs. We employ life cycle assessment to analyze six environmental impacts associated with producing greenhouse‐grown tomatoes in a Solar PoweRed INtegrated Greenhouse (SPRING) compared to conventional greenhouses with and without an adjacent solar photovoltaic array, across three distinct locations. The SPRING design produces significant reductions in environmental impacts, particularly in regions with high solar insolation and electricity‐intensive energy demands. For example, in Arizona, global warming potential values for a conventional, adjacent PV and SPRING greenhouse are found to be 3.71, 2.38, and 2.36 kg CO2 eq/kg tomato, respectively. Compared to a conventional greenhouse, the SPRING design may increase life cycle environmental burdens in colder regions because the shading effect of OPV increases heating demands. Our analysis shows that SPRING designs must maintain crop yields at levels similar to conventional greenhouses in order to be economically competitive. Assuming consistent crop yields, uncertainty analysis shows average net present cost of production across Arizona to be $3.43, $3.38, and $3.64 per kg of tomato for the conventional, adjacent PV and SPRING system, respectively.}, number={1}, journal={JOURNAL OF INDUSTRIAL ECOLOGY}, author={Hollingsworth, Joseph A. and Ravishankar, Eshwar and O'Connor, Brendan and Johnson, Jeremiah X. and DeCarolis, Joseph F.}, year={2020}, month={Feb} }