The majority of power generated by photovoltaic energy infrastructure is derived from ground-mounted solar arrays that prioritize energy production, minimize operating costs and, at best, accommodate limited ecosystem services. We argue that co-prioritizing ecosystem services and energy generation using an ecologically informed, 'ecovoltaics' approach to solar array design and operation will have multiple benefits for climate, biodiversity and the restoration. The majority of power generated by photovoltaic energy infrastructure is derived from ground-mounted solar arrays that prioritize energy production, minimize operating costs and, at best, accommodate limited ecosystem services. We argue that co-prioritizing ecosystem services and energy generation using an ecologically informed, 'ecovoltaics' approach to solar array design and operation will have multiple benefits for climate, biodiversity and the restoration of degraded lands.Download PDFUtility-scale solar installations can vary widely in their effect on ecosystem services3: land grading and removal of vegetation beneath PV panels has the strongest and most obvious negative effects. As a mitigation strategy, agrivoltaics — the co-location of agriculture and energy production — has emerged as an increasingly popular way to maintain some level of ecosystem services (that is, producing speciality crops or forage, or providing pollinator habitat) beneath PV arrays. Although there is some evidence for potential crop yield, water use and energy production benefits from agrivoltaics systems (particularly for crops grown beneath elevated panels)4, most large (>10 MW) agrivoltaics systems prioritize electricity generation and are designed on the basis of utility-scale PV principles (for example, generating the most electricity per unit land area). In other words, most agrivoltaics systems are still designed for energy production and secondarily rely on management to facilitate additional ecosystem services (Fig. 1).The vast majority of power generated by PV infrastructure globally is from utility-scale solar installations that are designed to maximize energy production per unit land area while minimizing cost and maintenance. As a result, the ecosystems in which they are placed are often minimally valued, resulting in negative effects on, or a total loss of, natural ecosystem integrity3 (left). Agrivo. PV panels generate substantial small-scale (approximately 1 m) environmental heterogeneity in sunlight, soil water and temperature across space and over time7 (Fig. 2). In particular, variability in light and the redistribution of precipitation shed from PV panels can strongly influence ecological processes below. For example, PV arrays have been shown to alter patterns of grassland plant productivity8,9, phenology10 and nutrient content of the plants beneath arrays11. Furthermore, well-established ecological theory predicts that increasing environmental heterogeneity, including spatial and temporal variability in resources, can increase biodiversity and alter ecosystem functioning. Thus, ecovoltaic designs would alter the spacing and operation of PV panels, on the basis of ecological principles, to target specific habitat modifications and generate environmental heterogeneity as a tool to restore, maintain and perhaps even enhance ecosystem services of the ecosystems beneath. In this way, ecovoltaics could build on past ecosystem restoration research12 that has assessed the value of increasing environmental heterogeneity as a means of increasing biodiversity13. Further, because environmental heterogeneity has been proposed to improve resilience to climate extremes such as droughts and heat waves14, ecovoltaics approaches might assist in achieving climate-change mitigation goals.Strategic. Ecovoltaic-induced environmental heterogeneity may be able to assist in the restoration of many degraded land-cover types in need of remediation. Ecovoltaic arrays specifically targeted to these lands will not only enable the more rapid implementation of solar energy, but also will provide alternatives to PV development in native ecosystems3. Below, we identify several types of land cover as candidates for an ecovoltaic approach.Water-limited agroecosystems, including rangelands (for example, those in warm and dry environments where potential evapotranspiration meets or exceeds precipitation), are prone to overutilization (for example, poor grazing management15) and may benefit the most from the strategic design of PV arrays16. These short-statured ecosystems are generally not light-limited and thus partial shading may have minimal effects, whereas reduced evaporative demand may be beneficial17. For example, in these grasslands — where both aridity and drought are predicted to become more severe — the concentration of rainfall via runoff from PV panels can emulate large rainfall events that have a disproportionately important role in controlling aridland ecosystem processes18 and may even partially rescue these ecosystems from drought19. As noted above, the structural complexity imparted by PV panels may also provide the habitat amelioration that is necessary for facilitating increased plant diversity a. PV arrays can themselves be somewhat diverse in their design, with clear differences in microclimatic consequences for the plants beneath. Fixed-axis panel arrays provide deep shade for shade-tolerant species and redistribute rainfall to a single panel edge, effectively concentrating this resource in consistent microsites. By contrast, single-axis.
