In 2016, Portland approved a 660-kilowatt solar array atop its old landfill. 10 years later, the former dump is a clean-energy site poised to power city operations today

An old landfill in Portland, Maine, is doing something quite different now. The site behind Ocean Avenue has become a home for solar energy. The City of Portland worked with ReVision Energy to install the system on the landfill cap. Completed in fall 2018, the project gave the closed site a useful second purpose.

That location is what makes the project worth a closer look. The land had already served its original purpose and was closed. Rather than simply leaving it that way, Portland found another use for the site. The solar system was expected to provide power and reduce CO2 emissions over a 40-year lifespan.

Why put solar panels on a closed landfill?

A closed landfill is not ordinary vacant land waiting for development. Its past use places limits on what can happen there later. That can make finding a practical second use more difficult for cities. Portland's project shows one way renewable energy can fit into that picture.


Solar panels can turn an underused site into productive infrastructure without changing its original history. In Portland, the landfill remained a closed site while its surface supported a new energy project. The approach also avoided treating the property as land with no future purpose. Instead, the city gave it another role that could last for decades.

What happened in Portland?

The City of Portland partnered with ReVision Energy to develop and install the solar system. ReVision Energy is a local employee-owned contractor that worked with the city throughout the project. The installation was completed in fall 2018.

The city did not choose its contractor after speaking with only one company. Portland spoke with six companies before signing a contract with ReVision Energy. The project description says the city was pleased with the entire process. That included the first meeting, contracting, scheduling and installation.

What makes the landfill site useful again?

The project's value comes partly from the land itself. The former landfill already existed as a closed city property. Solar development gave that space another function without changing the basic status of the site. The result was a connection between land reuse and renewable energy.

The expected 40-year lifespan also changes how the project can be viewed. This was not designed as a short-term experiment on an overlooked property. The system was expected to keep producing power while helping reduce CO2 emissions for many years. That makes the project's value extend well beyond its 2018 completion date.

Could other cities use old landfills for solar power?

Portland's experience does not mean every closed landfill can become a solar site. Different properties have different conditions and restrictions. Whether a particular landfill can support solar equipment depends on factors that are not provided in the project description. The Portland example does show that such reuse can be possible.

That matters as cities look for places where renewable energy can be developed. Existing properties can sometimes offer opportunities that would otherwise be overlooked. A closed landfill may not be suitable for conventional development, yet it can still have another productive use. Portland's project puts that idea into a very practical setting.

Who helped bring the project together?

The people behind the project were not limited to the crews installing the panels. Portland's process included meetings with multiple companies before the city selected ReVision Energy. Contracting and scheduling were also part of the work. Those details show how much planning sits behind a solar project that may look simple once it is finished.

ReVision Energy's role also gave the project a local connection. The company describes itself as employee-owned, and it worked directly with the City of Portland on the installation. The city said it was pleased with the contractor's work from the initial discussion through completion.

The most straightforward answer is that an old landfill gained a new purpose. The solar installation was designed to provide power while reducing CO2 emissions over its expected operating life. It also showed that renewable energy does not always have to begin with untouched or undeveloped land.

There is a broader lesson in that choice. Cities often have properties shaped by decades of past use, and some are difficult to redevelop in conventional ways. A project like Portland's asks a different question about those places. Instead of asking what the land used to be, it asks what useful role it can serve next.

The Portland, Maine solar project was completed in 2018, but its story is really about long-term reuse. A closed landfill became part of the city's energy landscape rather than remaining an idle piece of property. For roughly four decades, the site was expected to keep serving that new purpose. It is a modest example of a larger idea: sometimes renewable energy begins with finding a new use for land that already has a past.