This study introduces a new separation model capable of accurately estimating the diffuse component from the global photosynthetically active radiation and conveniently retrievable meteorological parameters.
This paper shares an overview of both active and passive cooling approaches in solar PV applications with an emphasis on newly developed agrivoltaic natural cooling systems.
This study focused on the photosynthetic photon flux density and employed an all-climate solar spectrum model to calculate the photosynthetic photon flux density accurately on farmland partially shaded by solar panels and supporting tubes. The researchers also described an algorithm for estimating the photosynthetic photon flux density values under solar panels, which were then validated using photosynthetic photon flux density sensors. The calculation formula enables farmers to evaluate the economic efficiency of a system before introducing it.
In this article, researchers argue that the divide between food and energy production groups can be lessened with the co-generation of food and energy on the same land. This paper demonstrates the importance of different light spectra, and show that those spectra, if optimized in terms of their utilization, could lead to sustainable and more efficient food and energy systems.
Researchers in this study monitored soil and air temperature, humidity, wind speed, and incident radiations at a full sun site, as well as at two agrivoltaic systems with different densities of photovoltaic panels. They recorded the findings during three seasons (winter, spring, and summer) with both short cycle crops (lettuce and cucumber) and a long cycle crop (durum wheat). The researchers concluded that little adaptations in cropping practices should be required to switch from an open cropping to an agrivoltaic cropping system and attention should mostly be focused on mitigating light reduction and on selection of plants with a maximal radiation use efficiency in these conditions of fluctuating shade.
Researchers in this study used experimental panels to simulate the effects of solar development on microhabitats and annual plant communities present on gravelly bajada and caliche pan habitat, two common habitat types in California’s Mojave Desert. They evaluated soils and microclimatic conditions and measured community response under panels and in the open for seven years. The study’s results demonstrate that the ecological consequences of solar development can vary over space and time and suggest that a nuanced approach will be needed to predict impacts across desert landforms differing in physical characteristics.
This research addresses the concern that photovoltaic systems create a “heat island” effect. Researchers examined the heat island effect with experiments spanning three biomes and found that temperatures over a photovoltaic plant are regularly 3–4°C warmer than wildlands at night, a direct contrast to other studies based on models that suggested that PV systems should decrease ambient temperatures.
When installing photovoltaic panels on agricultural land, one of the most important aspects to consider are the effects of the shadows of the panels on the ground. This study presents a valid methodology to estimate the distribution of solar irradiance in agrivoltaic installations as a function of the photovoltaic installation geometry and the levels of diffuse and direct solar irradiance incident on the crop land.
Decomposition models of solar irradiance estimate the magnitude of diffuse horizontal irradiance from global horizontal irradiance. These two radiation components are well-known to be essential for the prediction of solar photovoltaic systems performance. In open-field agrivoltaic systems, that is the dual use of land for both agricultural activities and solar power conversion, cultivated crops receive an unequal amount of direct, diffuse and reflected photosynthetically active radiation (PAR) depending on the area they are growing due to the non-homogenously shadings caused by the solar panels installed (above the crops or vertically mounted). It is known that PAR is more efficient for canopy photosynthesis under conditions of diffuse PAR than direct PAR per unit of total PAR. For this reason, it is fundamental to estimate the diffuse PAR component in agrivoltaic systems studies to properly predict the crop yield.
Solar electricity from solar parks in rural areas are cost effective and can be deployed fast therefore play an important role in the energy transition. The optimal design of a solar park is largely affected by income scheme, electricity transport capacity, and land lease costs. Important design parameters for utility-scale solar parks that may affect landscape, biodiversity, and soil quality are ground coverage ratio, size, and tilt of the PV tables. Particularly, low tilt PV at high coverage reduces the amount of sunlight on the ground strongly and leads to deterioration of the soil quality over the typical 25-year lifetime. In contrast, vertical PV or an agri-PV designed fairly high above the ground leads to more and homogeneous ground irradiance; these designs are favored for pastures and croplands. In general, the amount and distribution of ground irradiance and precipitation will strongly affect which crops can grow below and between the PV tables and whether this supports the associated food chain. As agrivoltaics is the direct competition between photosynthesis and photovoltaics. Understanding when, where and how much light reaches the ground is key to relate the agri-PV solar park design to the expected agricultural and electricity yields. We have shown that by increasing the minimum height of the system, decreasing the size of the PV tables and decreasing the coverage ratio, the ground irradiance increases, in particular around the gaps between the tables. The most direct way of increasing the lowest irradiance in a solar park design is to use semi-transparent PV panels, such as the commercially available bifacial glass-glass modules. In conclusion: we have shown that we can achieve similar ground irradiance levels in an east- and west-facing design with 77% ground coverage ratio as is achieved by a south-facing design at 53% coverage.
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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
