Curitiba built Latin America's first landfill solar plant on its closed Caximba dump

The Caximba landfill was decommissioned in 2010, leaving Curitiba a difficult piece of ground. In 2023 the city inaugurated a solar power plant on top of it during the city's 330th anniversary celebrations — a 4.55 MW installation nicknamed the 'solar pyramid' for its shape, and the first solar plant built on a landfill in Latin America.

The project belongs to 'Curitiba Mais Energia', one of the city's initiatives to combat and mitigate climate change. Nearly 8,600 photovoltaic modules feed the grid of Copel (Companhia Paranaense de Energia Elétrica), with the value credited against the municipality's electricity bills — estimated monthly savings of 30% on the bills of municipal public buildings, about R$2.65 million a year that can be reinvested, plus 2,000 tons of CO2 avoided.

Grupo Bonö Energia, the engineering and project development firm, says the design took about two years of studies to overcome soil and terrain challenges no photovoltaic system in the country had faced. The R$28 million investment came through partnerships: the project was selected by the C40 Cities network and funded by the C40 Cities Finance Facility, supported by GIZ and funded by Germany's BMZ, the UK's BEIS and USAID, complying with Aneel's Distributed Generation regulations.

4.55 MW on ~8,600 panels; ~30% monthly savings on municipal building bills, R$2.65M a year; 2,000 tons of CO2 avoided; ROI in about five years on a R$28M investment.

First-in-region projects de-risk the category for every other municipality — the engineers published a benchmark, not just a plant.

The financing is the model: international climate funds (C40 CFF, GIZ, BMZ, BEIS, USAID) carried a R$28M investment with a five-year payback.

Crediting generation against its own bills makes the city its own offtaker — the savings land on consumption the city already pays for.

A closed landfill's liabilities — unstable soil, tricky terrain — become a solar site when the engineering is done first: two years of studies bought a first-in-Latin-America asset.

The plant was inaugurated during the city's 330th anniversary celebrations and presented at the opening of Smart City Expo Curitiba 2023; Grupo Bonö expects it to become the reference for landfill solar projects across Brazil.