Ottawa Launches Sewage Energy Project at LeBreton Flats

OTTAWA -

Ottawa is embarking on a groundbreaking initiative to harness the latent thermal energy within its wastewater system, marking a significant stride toward sustainable urban development. The Sewage Energy Exchange System (SEES) project, a collaborative effort led by the LeBreton Community Utility Partnership—which includes Envari Holding Inc. (a subsidiary of Hydro Ottawa) and Theia Partners—aims to revolutionize how the city powers its buildings.

Harnessing Wastewater for Sustainable Energy

The SEES will utilize advanced heat pump technology to extract thermal energy from the city's wastewater infrastructure, providing both heating and cooling to buildings within the LeBreton Flats redevelopment. This innovative approach eliminates the need for fossil fuels, aligning with Ottawa's commitment to reducing greenhouse gas emissions and promoting clean energy solutions.

The system operates by diverting sewage from the municipal collection network into an external well, where it undergoes filtration to remove large solids. The filtered water is then passed through a heat exchanger, transferring thermal energy to the building's heating and cooling systems. After the energy is extracted, the treated water is safely returned to the city's sewer system.

Environmental and Economic Impact

Once fully implemented, the SEES is projected to deliver over 9 megawatts of heating and cooling capacity, servicing approximately 2.4 million square feet of development. This capacity is expected to reduce greenhouse gas emissions by approximately 5,066 tonnes annually—equivalent to the electricity consumption of over 3,300 homes for a year. Such reductions are pivotal in helping Ottawa meet its ambitious goal of achieving a 96% reduction in community-wide greenhouse gas emissions by 2040, as outlined in its Climate Change Master Plan and Energy Evolution strategy.

Integration with the Odenak Development

The first phase of the SEES will support the Odenak development, a mixed-use project comprising two high-rise residential buildings. This development is poised to be Canada's largest residential zero-carbon project, featuring 601 housing units, with 41% designated as affordable housing. The integration of the SEES will ensure that Odenak operates entirely on renewable energy, setting a benchmark for future urban developments.

Broader Implications and Future Expansion

The SEES project is not just a localized initiative; it represents a scalable model for sustainable urban energy solutions. The LeBreton Community Utility Partnership is in discussions with the National Capital Commission to explore extending the SEES network to additional parcels within the LeBreton Flats redevelopment. Expanding the system could lead to economies of scale, further reducing costs and enhancing the environmental benefits.

Ottawa's venture into wastewater-based energy systems places it at the forefront of a growing trend in North America. Cities like Toronto and Vancouver have initiated similar projects, and European counterparts have long utilized sewage heat recovery systems. Ottawa's adoption of this technology underscores its commitment to innovation and sustainability in urban planning.

The SEES project at LeBreton Flats exemplifies how cities can repurpose existing infrastructure to create sustainable, low-carbon energy solutions. By transforming wastewater into a valuable energy resource, Ottawa is setting a precedent for environmentally responsible urban development. As the city moves forward with this initiative, it not only addresses immediate energy needs but also contributes to a cleaner, more sustainable future for its residents.