The landscape of the former factory does not vanish. It remains — compacted, contaminated, and charged with a latent energy that cannot simply be left to decay.

Post-industrial sites, commonly known as brownfields, are properties complicated by the presence or potential presence of hazardous substances. They represent one of the most pressing challenges of urban and peri-urban planning in the twenty-first century. The U.S. Environmental Protection Agency (EPA) estimates that there are approximately 450,000 brownfields in the United States alone. These sites are frequently located near existing road networks and power transmission lines, which are precisely the conditions that make them ideal candidates for large-scale solar energy development (EPA, 2024).

Solar energy collection is governed by well-established physical principles. The single most important variable is the solar irradiance arriving at a surface, which Goswami et al. define as “the rate at which radiant energy is incident on a surface per unit area of the surface” (Goswami, Kreith & Kreider, 2000, p. 30). In practical engineering terms, this means that even land unsuitable for agriculture or housing can yield considerable energy output if correctly oriented and equipped. The global solar energy resource is immense: the Earth receives approximately 1.3 x 10^17 watts of solar power at any given moment, of which photovoltaic systems can convert a meaningful fraction to usable electricity. The average conversion efficiency of commercial silicon photovoltaic modules is between 15% and 22%, a figure that continues to improve with advances in cell architecture (National Renewable Energy Laboratory, 2024).

The application of these principles to post-industrial terrain requires careful engineering. Unlike agricultural or greenfield sites, brownfield substrates frequently have poor load-bearing capacity due to decomposing waste, compacted fill, or residual industrial materials. This requires the use of non-penetrating, ballasted mounting systems that distribute the weight of solar arrays across the surface without disturbing contaminated soil layers or breaching engineered landfill caps. The National Renewable Energy Laboratory, in collaboration with the EPA, has developed specific guidelines for this type of installation, noting that “careful design ensures that photovoltaic construction neither worsens contamination nor destabilizes the underlying substrate” (NREL/EPA, 2021). The engineering approach must therefore integrate standard solar site assessments — including solar access analysis, tilt and azimuth optimization, and shading calculations — with specialized geotechnical and environmental surveys.

The economic rationale for siting solar power on these degraded lands is compelling. Traditional remediation of a heavily contaminated brownfield can cost tens of millions of dollars for a single site. Solar development offers an alternative path: rather than removing contamination, the contaminated zone is capped and stabilized as a condition of the solar lease. The revenue from electricity sales, combined with federal and state incentive structures such as those introduced by the U.S. Inflation Reduction Act of 2022, can offset site development costs and generate a steady return for municipal authorities. The American Clean Power Association reports that transforming a brownfield into what the industry terms a “brightfield” creates local employment during construction, adds to the property tax base, and can raise surrounding property values (ACP, 2023). The concept of the brightfield — a brownfield repurposed for solar energy — has gained formal recognition in U.S. federal policy precisely because it achieves two objectives simultaneously: environmental remediation and clean energy production.

There are real challenges in this work. Soils degraded by heavy industry may contain volatile organic compounds, heavy metals, or radioactive materials that require containment, not excavation. Adjacent communities, many of them low-income and disproportionately affected by decades of industrial pollution, have legitimate concerns about any activity that might disturb site containment. The engineering response is to prioritize minimal-disturbance construction methods, rigorous monitoring, and transparent reporting. The broader social dimension is equally important: solar development on brownfields is one of the more direct mechanisms available for placing clean energy infrastructure and its economic benefits in communities that have historically borne the cost of industrial activity without proportional benefit (Borgen Project, 2023).

The physics of solar energy conversion does not change when the ground beneath the panels is contaminated. What changes is the layer of engineering judgment, environmental compliance, and community engagement required to bring a project into operation. Goswami and colleagues emphasize that “the design of solar energy systems must account for local meteorological data, site geometry, and the characteristics of the solar collection equipment in an integrated manner” (Goswami et al., 2000, p. 5). In post-industrial contexts, this integration must extend beyond purely meteorological and mechanical variables to include ecological and social ones. The engineer working on a former coking plant or a decommissioned military facility is not only optimizing panel tilt angles and inverter sizing; they are also contributing to the remediation of a landscape and the regeneration of a community.

Across Europe and North America, successful projects demonstrate that this integration is achievable. In the Netherlands, former industrial harbor areas have been converted to photovoltaic installations providing power to thousands of households. In the United States, the EPA’s RE-Powering America’s Land Initiative has facilitated more than 530 renewable energy projects on contaminated lands, with solar energy comprising 93% of those developments (EPA, 2024). These are not small-scale demonstrations; some installations exceed 10 megawatts of peak capacity and supply power to regional grids under long-term power purchase agreements.

The combination of established solar engineering science and the urgent need to address post-industrial land legacies makes this one of the more rational and practical applications of renewable energy technology available today. The land already exists. The contamination is already there. The solar resource is constant and free. The remaining variable is the quality and ambition of the engineering and policy frameworks applied to bring these elements together. That is a solvable problem.

Author: Ing. Anfilov

References

• American Clean Power Association (ACP). (2023). Brightfields: Solar Development on Brownfields. Washington, DC: ACP.
• Borgen Project. (2023). Environmental Justice and Renewable Energy Siting. Retrieved from borgenproject.org.
• Goswami, D. Y., Kreith, F., & Kreider, J. F. (2000). Principles of Solar Engineering (2nd ed.). Philadelphia: Taylor & Francis.
• National Renewable Energy Laboratory (NREL). (2024). Best Research-Cell Efficiency Chart. Golden, CO: NREL.
• NREL/EPA. (2021). Siting Solar PV on Closed Landfills and Superfund Sites. Washington, DC: U.S. Environmental Protection Agency.
• U.S. Environmental Protection Agency (EPA). (2024). RE-Powering America’s Land Initiative. Washington, DC: EPA Office of Land and Emergency Management.
• U.S. Inflation Reduction Act. (2022). Public Law 117-169. Washington, DC: U.S. Government Publishing Office.