These cities are building solar plants on trash to save space

Old landfill sites are difficult to repurpose, which is why they tend to sit idly for decades. That’s a problem in a world with finite land resources, lots of waste, and ever-growing energy requirements.

With this in mind, some cities and project developers are realising that clean energy and dirty landfills are actually well suited. Plus, landfills tend to be located close to electricity consumption hubs and grid connection points.

The latest: A new 59MW solar farm near Essex, in the UK, was built atop a 5-million-tonne sealed landfill site that’s sat unused for 25 years.

Now, in its second life, the facility will generate enough power for 17,000 homes, and the trash below the soil — which would emit large amounts of planet-warming methane if exposed — will remain untouched.

“We are repurposing land that would otherwise go unused to supply clean power from a source next door to London, where significant demand for renewable energy lies,” said Anthony Doherty, chief investment officer at NTR, the group behind the project.

While one of the largest such projects to date, this certainly isn’t the first.

Earlier in 2023, the first solar plant built on a former landfill site in Latin America was commissioned.

The Solar Pyramid project in Curitiba, Brazil, “serves as an example to cities across Brazil and Latin America of how to deliver clean, affordable energy while reducing a city’s dependence on the urban energy grid, often reliant on fossil fuels,” according to C40, which provided funding for it.

Other solar landfill projects have been completed in the US states of Rhode Island, California and Massachusetts, in Stoke-on-Trent in the UK, and in Germany.

In Australia, meanwhile, the New South Wales government plans to turn an old landfill site into a big battery storage facility.

Yes, but: Solar projects on landfill sites are more challenging than conventional ones, because developers must ensure the foundations holding the panels in place don’t pierce the seals covering old trash. That brings extra costs.

The cost per unit of electricity produced is roughly 5% more than a solar farm installed on ordinary land, according to this Bloomberg report. In some cases, the costs are 15% higher.