Decommissioning FAQ

Most land-leasing agreements for large-scale solar projects run 20–30 years, often with an optional 10-year extension. When the contract ends, two outcomes are possible: repowering or decommissioning.

Repowering means replacing solar panels while reusing existing infrastructure such as racking and cabling. Decommissioning involves removing the system and restoring the site according to project agreements and regulatory requirements.

More information on end-of-life options is available in the Center for Rural Affairs Decommissioning Solar Energy Systems Resource Guide.

When submitting a CPCN, applicants for solar and wind energy projects are required to outline how the facility will be decommissioned at the end of its lifespan. Applicants describe expected timelines, actions required to perform decommissioning, and site restoration plans.

For solar projects, a preliminary decommissioning plan is often included as an attachment to a project application. A more detailed plan can also be negotiated through a Joint Development Agreement.

For wind energy projects, applicants are also required to outline project decommissioning as part of the CPCN application process.

State legislation does not include specific standards for decommissioning solar energy systems, so solar decommissioning plans are evaluated on a case-by-case basis by the Public Service Commission (PSC). For wind energy systems, PSC 128.19 sets standards for decommissioning and site restoration requirements, which can be referred to for further details on state law requirements for wind energy generating systems.

• To view Application Filing Requirements for Solar Energy Projects: AFR Solar
• To view Application Filing Requirements for Wind Energy Projects: AFR Wind

For wind energy systems, the owner of the wind energy facility (developer or utility) is responsible for the actions and costs required to decommission the system. The owner is also required to restore the site to pre-construction conditions unless otherwise agreed with the participating landowner. Although Wisconsin law does not explicitly name responsible parties for solar projects, responsibility generally falls to the developer or site operator.

Decommissioning plans submitted during the CPCN process do not always include who will pay for decommissioning, when decommissioning will occur, who is responsible, the financial assurances to the local government for decommissioning, or the details of what solar components will be removed. For wind energy systems, PSC 128.19(3)(b) allows local governments to require bonds, escrow accounts, or letters of credit to help ensure decommissioning funds are available. Communities often apply similar approaches to solar projects.

For examples of Joint Development Agreements for solar energy facilities that included decommissioning standards, refer to Solar Contracts Worksheet (Row 9). Font in blue includes preferred contract language identified by UWSP Center for Land Use Education.

For a real-world example, the Town of Lyndon Decommissioning Plan includes detailed decommissioning steps and financial assurances.

Because most solar facilities are still within their operating life, large-scale decommissioning is only beginning to occur in the United States.  However, many components can be reused or recycled. Aluminum frames, wiring, and clean glass can be easily recycled. The US Environmental Protection Agency has information about Solar Panel Recycling. The Department of Natural Resources has a guidance document about Managing Used Solar Panels and Components.

There have been no large-scale solar energy generating facilities that have been decommissioned in Wisconsin. The oldest operating solar energy generating facility larger than 100 megawatts (MW) was approved by the PSC in 2019 (Two Creeks Solar Park in Manitowoc County) and started operating in 2020. Solar land leases generally last 25-30 years. Sometimes, owners of the system will re-panel the system rather than decommission. 

However, there has been one wind energy system decommissioned in Wisconsin. In 2018, the Lincoln Wind Energy Facility in Kewaunee County (9.4 MW) was decommissioned after 20 years of operation.

• For additional information on decommissioning process for wind and related structures: Wind Energy End-of-Service Guide | Department of Energy
• For decommissioning estimates for wind energy systems (national): Decommissioning Wind Energy Systems Resource Guide WEB.pdf

When submitting a CPCN, applicants for solar energy projects are asked to describe how the facility will be decommissioned at the end of its lifespan, expected timelines and actions required to perform decommissioning, and whether participating landowners could ever be deemed responsible for decommissioning costs in any situation.

Applications for projects larger than 100 megawatts are required to submit plans to minimize the impact on the long-term agricultural potential of the site, including practices to minimize damage to soils and tile drainage, and plans to restore the site.