Environmental and Social Impacts of Solar Energy Brief

In developing this sustainability report, we considered it pertinent to address the various negative impacts of solar energy on people and the planet. The following is a brief summary of key areas for improvement within the solar industry.

Introduction

Renewable energies have high environmental and socio-economic benefits and less impact on the environment than traditional fossil-fueled energy production methods, such as coal or natural gas plants. Lifecycle assessments of the GHG emissions of various energy sources from cradle to grave of three studies indicate that the GHG emissions of solar energy are up to 10-20x lower than traditional fossil fuel-based energy production.[1] Socioeconomic benefits of solar energy include regional and national energy independence, increased work opportunities, stable energy sources, and deregulated energy markets. Developing countries are particularly aided by these benefits.[2] All renewable energy technologies have some negative environmental and/or social impacts, and solar is not without its own unique challenges.[3]

1. Resource Extraction and Manufacturing

Heliolytics does not directly impact or shape these stages of a solar module’s lifecycle, however, we felt it important to address them within this analysis.

The extraction and refining of materials required to manufacture PV cells contribute significantly to the environmental impact of the solar industry, making this a key area for improvement. The most severe of these impacts include human toxicity, marine ecotoxicity, and metal depletion. These environmental impacts are driven by the following key substances:[4]

Arsenic Copper Electricity consumption Glass production Lead Mercury Nickel to air generated from silver paste Silver used for silver paste production

Of these, it is the electricity used during the transformation of metallic silicon into solar silicon that has the greatest environmental impact. This is due to an extremely energy-intensive process, and because solar modules are primarily manufactured in China where the majority of electricity is produced by burning coal.[5] The greatest opportunities for environmental impact reduction during solar module production include the selection of recycled rather than primary materials, increasing electricity and silver paste utilization efficiency, promoting the development of the solar industry, and installing solar energy systems in regions with high solar radiation intensity and fossil fuel-intensive energy grids.[4]

One of the greatest negative social impacts of this stage of the solar life cycle comes from the mining and refining of solar-grade polysilicon. Currently, about 95% of solar modules rely on solar-grade polysilicon as a primary material. Polysilicon manufacturers in the Uyghur Region produce 45% of the global solar-grade polysilicon supply. Recent investigations into government and corporate sources have exposed that coercion and the threat of internment drive the labor that sources this polysilicon. Indigenous workers are unable to refuse or leave these jobs — equating the process to “forcible transfer of populations and enslavement.”[6] All polysilicon manufacturers in this region have admitted to participating in these internment labor transfer programs.[6] An issue that arises when looking to hold polysilicon manufacturers responsible for these abuses is that module manufacturers do not always have clear insight into their raw material supply chains. To maintain control over the materials they purchase and to ensure that the production of those materials complies with human and environmental rights, module manufacturers must take care to develop supply chain oversight and diversity. Not only will this allow them to have greater control over their supply chain, but it will give them more visibility into the origin of their raw materials and enable them to divert their purchasing decisions away from materials that are produced unethically.

2. Construction and Maintenance

At Heliolytics, assisting our clients in ensuring net positive outcomes during the operational phase of their solar assets is integral to our mission. This applies to power production, environmental resilience, and co-benefits. We are assessing potential products that can be used to support some of the goals discussed in the following section. Building solar arrays, especially utility-scale solar energy (USSE) systems, disturbs soil through land modification that disrupts carbon, water, and vegetative cycles. Existing vegetation is removed and the surface is graded and filled.[7, 8] The soil and vegetative disturbances caused by USSE installations can release trapped carbon into the air, degrade soil, increase erosion and runoff, and increase surrounding air temperatures. While research in this area is ongoing, a useful strategy in mitigating the effects of these impacts is through revegetation with land cover crops.

Carbon-sequestering vegetation varies in growth behavior across climate regions, so an approach that is tailored to the local ecosystem and climate is required to ensure appropriate crop selection. It is likely that revegetation alone is not enough to completely restore the soil health to its previous state, even after several years. Therefore, additional measures should be taken during the construction process to minimize soil disturbances and removal.[7]

Coordinated planning and regulation of solar installations and land management below the solar panels are critical to maintaining local carbon cycles.[9] Following local, regional, and national environmental regulations, as well as prioritizing local risks and opportunities, can all help mitigate the risk of significantly harmful land-use change for USSE.[10]

USSE projects may cause habitat fragmentation leading to negative ecological impacts, particularly when they are in close proximity to sensitive or protected ecological areas.[10] Negative impacts on biodiversity that arise as a result of solar energy projects include avian mortalities, insect disorientation, the creation of microclimates, and habitat fragmentation.[3] It is worth noting, however, that USSE-related avian mortality rates are similar to those estimated for wind energy, and both comprise a very small portion of causal factors of avian mortality in the United States. The causal factors of the avian mortality rates as a result of USSEs are not fully understood, and standardized data collection and research into the cause of these fatalities needs to be explored to best mitigate these adverse outcomes.[1]

Land-use change is also a potential threat to pollinator populations. While large-scale, pesticidedriven monocultures can be detrimental to pollinators, more than 70% of agriculture worldwide relies on bee pollinators alone. The revegetation of USSEs, if planned and managed correctly as biodiverse and regenerative spaces, can offer further potential opportunities for supporting other ecosystem services including pollination and agricultural production.[7] In these instances, USSE construction can even be of net benefit to pollinator communities through providing restored habitat, supporting conservation efforts, and strengthening ecological networks.[11]

Incorporating agrivoltaic practices, such as sheep grazing, can work symbiotically with revegetation strategies. Agrivoltaics work to limit or eliminate the need for vegetation removal and maintenance while supporting food production.[8]

Collectively and individually, these negative impacts must be considered in energy policy in tandem with potential positive impacts to drive the most effective outcomes for both energy production and habitat protection.[3] Co-benefits of making these improvements include reducing the impact on areas of cultural or ecological significance, assisting in garnering public acceptance of solar installations,[2] and driving support and demand for more projects in the future.

3. Decommissioning and Recycling

Heliolytics does not currently operate within this stage of the solar life cycle, though we are looking into ways we can support the industry in making better decisions when it comes to decommissioning and recycling.

Two of the most impactful ways to reduce the life cycle impact of solar cell production is to reduce the number of new solar panels that need to be manufactured and the number of resources required to make them. Reuse is a much more desirable outcome from an environmental and cost perspective. Additionally, this decreases the resources needed to bring more solar online. Takeback programs are helpful options to ensure that modules are being refurbished or recycled.[12] One study suggests that the total impact of solar cells on the environment could be reduced by up to 58% by using recycled silicon materials, effectively making their impact two times lower than those made of entirely primary materials.[13]

Different scales of solar installations have different challenges regarding disposal. While utility-scale solar may be able to find efficiencies due to the scale of the sites they are decommissioning, this can be more of a challenge for residential or commercial projects where far fewer modules are spread out over a larger area.[12] As it becomes increasingly costeffective to make solar modules, another challenge is that the amount of valuable materials in them is also declining, increasing the economic challenge of recycling.[13] Government policy can be a good mechanism for ensuring that solar modules are being disposed of responsibly at their end of life.[12] Currently, better policy is certainly required in North America.[14] While some states in the U.S. have passed bills that aim to enforce best practices for module disposal during decommissioning, the country overall is lagging when compared to the E.U.[12] The E.U. Waste Electrical and Electronic Equipment Directive requires module manufacturers to build in the cost of collecting and recycling decommissioned modules, ensuring that doing so is economically viable.[14]

The issue of decommissioning and recycling poses such a risk for the long-term viability of the industry that, if not addressed and a solution quickly found, it could erode public trust in solar as an environmentally sound choice for building out energy capacity moving forward.[13] The bottom line is that until this loop is closed, the solar industry cannot be truly sustainable.[12] PV waste is perhaps our industry’s greatest challenge right now, but can also be a rewarding economic opportunity if the industry can find the right path forward.[14] At Heliolytics, we see it as imperative that the industry will adopt circularity into project design and operations to ensure that solar energy maintains positive environmental outcomes and a broad social license to operate.

4. Racial Inequities

Within the U.S. solar market, the racial disparity of solar jobs and ownership is one of the most pressing social issues. While Black workers represent 13% of the U.S. labor force, they account for only 7.7% of the solar industry’s workforce. Additionally, neighborhoods with majority Black or Hispanic populations are much less likely to have solar rooftop installations than majority White neighborhoods, even after disparities in income and homeownership rates have been accounted for.[15] Black communities suffer from a lack of initial deployment, leading to to reduced installation in the long term, which is thought to be connected to the lack of racial diversity in the industry. This drives wealth inequalities even further as the installation of home solar can provide economic benefits to the owners through reduced electricity costs, tax credits, feed-in tariffs, and rebates.[16]

This echoes the larger issue of environmental racism that is present in the U.S. For example, majority Black neighborhoods have higher levels of air pollution, and now, benefits from solar are primarily accruing in neighborhoods outside their own. This disparity negatively affects those communities directly, but also impacts the viability of the solar industry overall due to resentment or potential loss of public support.[15]

There is a clear gap that exists and must be closed to ensure that the benefits of renewable energy - environmental, economic, and social - are being distributed equitably.[15] There needs to be a better understanding of what drives these disparities in the industry to determine pathways to equity.[16]

Companies that are operating within the solar lifecycle should look to external support to identify ways that they can support their racialized employees and the racialized communities they work in as a way to address this issue. Heliolytics is working to close this gap through its participation with Diversio to produce its first diversity survey and action plan.