Not every location has the desirable characteristics for installing a solar module or array with a clear, unobstructed view of the sun. For example, the owner of a house with east and west-facing roofs needs to determine which direction will gain the most output from the sun, without having to design and install a costly tiltmount racking system. Are there nearby structures (buildings, trees, utility poles or towers) which cast shade on the desired location? If so, what times of the day, and months of the year is the shade problematic? Can the module or array be mounted on the ground, or on a pole? These issues may be dealt with by considering different module or array mounting options.
Tag Archive for: Solar
Evaluating the albedo impact on bifacial PV systems based on case studies in Denver, USA and Västerås, Sweden. This study aims to develop a simulation and optimization tool for bifacial photovoltaic (PV) modules based on the open-source code OptiCE and evaluate dynamic and static albedo impact on a bifacial PV system. Further, a review of the market price development of bifacial PVs’ and an optimization to maximize energy output was conducted.
Agrivoltaic systems, consisting of the combination of photovoltaic panels (PVPs) with crops on the same land, recently emerged as an opportunity to resolve the competition for land use between food and energy production. Such systems have proved efficient when using stationary PVPs at half their usual density. Dynamic agrivoltaic systems improved the concept by using orientable PVPs derived from solar trackers. They offer the possibility to intercept the variable part of solar radiation, as well as new means to increase land productivity. The matter was analysed in this work by comparing fixed and dynamic systems with two different orientation policies. Performances of the resulting agrivoltaic systems were studied for two varieties of lettuce over three different seasons.
This study examines the crop outputs for Swiss chard, kale, pepper, and broccoli in an AV system with different gap spacings of 2, 3, 4, or 5 feet (AV plots) between panel clusters within rows to determine how much spacing between solar panels is optimal for crop production by comparing these system yields to full sun crop production. This study also examines the effect of the AV system on crop nutrient levels, on soil water content, and crop leaf temperature below the panels.
Kale, chard, broccoli, peppers, tomatoes, and spinach were grown at various positions within partial shade of a solar photovoltaic array during the growing seasons from late March through August 2017 and 2018.
As an answer to the increasing demand for photovoltaics as a key element in the energy transition strategy of many countries—which entails land use issues, as well as concerns regarding landscape transformation, biodiversity, ecosystems and human well-being—new approaches and market segments have emerged that consider integrated perspectives. Among these, agrivoltaics is emerging as very promising for allowing benefits in the food–energy (and water) nexus. Demonstrative projects are developing worldwide, and experience with varied design solutions suitable for the scale up to commercial scale is being gathered based primarily on efficiency considerations; nevertheless, it is unquestionable that with the increase in the size, from the demonstration to the commercial scale, attention has to be paid to ecological impacts associated to specific design choices, and namely to those related to landscape transformation issues. This study reviews and analyzes the technological and spatial design options that have become available to date implementing a rigorous, comprehensive analysis based on the most updated knowledge in the field, and proposes a thorough methodology based on design and performance parameters that enable us to define the main attributes of the system from a trans-disciplinary perspective. The energy and engineering design optimization, the development of new technologies and the correct selection of plant species adapted to the PV system are the areas where the current research is actively focusing in APV systems. Along with the continuous research progress, the success of several international experiences through pilot projects which implement new design solutions and use different PV technologies has triggered APV, and it has been met with great acceptance from the industry and interest from governments. It is in fact a significant potential contribution to meet climate challenges touching on food, energy, agriculture and rural policies. Moreover, it is understood—i.e., by energy developers—as a possible driver for the implementation of large-scale PV installations and building integrated agriculture, which without the APV function, would not be successful in the authorization process due to land use concerns. A sharp increase is expected in terms of number of installations and capacity in the near future. Along this trend, new concerns regarding landscape and urban transformation issues are emerging as the implementation of APV might be mainly focused on the efficiency of the PV system (more profitable than agriculture), with insufficient attention on the correct synergy between energy and food production. The study of ecosystem service trade-offs in the spatial planning and design for energy transition, to identify potential synergies and minimize trade-offs between renewable energy and other ecosystem services, has been already acknowledged as a key issue for avoiding conflicts between global and local perspectives. The development of new innovative systems (PV system technology) and components (photovoltaic devices technology) can enhance the energy performance of selected design options for APV greenhouse typology.
The report explores how the bifacial PV (biPV) technology can be optimized for various crops in fixed tilt and single-axis tracking AV systems.
The intent of this report is to help qualified individuals maintain and inspect PV systems safely. Qualification to conduct such inspections is earned by direct on-the-job training under qualified supervision or through training programs offered by accredited educational institutions or manufacturers. It should be noted that many testing and maintenance activities require two people to be performed safely and efficiently. Currently, an employee who is being trained for a task, demonstrates the ability to perform duties related to that task safely, and is under the direct supervision of a qualified person is usually considered to be a qualified person. As the number of U.S. PV installations grows, the industry will increasingly focus on O&M. PV systems have multi-decade lifetimes, and regular O&M helps optimize an installation’s ROI over its life. There are currently three working groups focused on this issue, and they will develop a more comprehensive O&M approach in the next few years. In the meantime, this report serves as an introduction to O&M for PV installations. The conclusions of this introductory report include: To maintain quality control and safety standards, it is important that only qualified personnel work on PV installations. It is not always easy, however, to identify qualified personnel. The authors suggest skill and knowledge guidelines for PV technicians in the Qualified Personnel section of the INTRODUCTION chapter; Safety is a serious concern when servicing PV installations. Early PV systems often had maximum system voltages less than 50 Vdc, but 600 Vdc systems are now common, and 1,000 Vdc systems are allowed by code in commercial and large-scale installations. Safety considerations require that qualified personnel use properly rated equipment and be trained for servicing the higher voltage systems; Qualified personnel should always work in teams of two people when working on live equipment. In addition, on a given jobsite, there should always be at least two qualified persons trained in CPR; Not all installations have appropriate signage, and qualified persons must be trained to recognize potential hazards with or without signage present; System uptime and availability is a key objective of O&M. Inverters that are offline can have a dramatic negative impact on the ROI of a PV system. Inverter failure rates are important to ROI, but even more important than how often an inverter goes offline is how quickly it can be placed back into service; Low power production also impacts ROI, and O&M personnel need effective strategies for identifying and correcting problems quickly. One specific recommendation is to stock critical parts that have long supply lead times.
This paper presents a novel 3D agrovoltaic modelling tool developed in python which enables technical and economical evaluation of potential agrovoltaic designs. It has been designed and applied for fruit crops which typically have a crucial flowering period. To illustrate the potential of this tool, a case study for pear trees in Bierbeek, Belgium is shown. While many geometrical parameters of agrovoltaic systems are fixed in practice, however, there is also the need to model the impact of PV modules on the tree light interception. The results of the modelling show that the amount of solar radiation depends on the modules used, with semi-transparent modules offering better light distribution and reduced crop loss. Based on the modelling, a prototype agrovoltaic set-up with pear trees and semitransparent modules has been built in Bierbeek, Belgium.
A slide presentation by Ku Leuven focusing on suitable sites for agrivoltaics in a pear orchard.
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Harvesting the Sun, the Agrisolar Short Film, is Available Now!March 20, 2024 - 5:52 pm
Case Study: Alaska AgrivoltaicsMarch 20, 2024 - 10:07 am
