Colloide is pleased to be working with Recirc Energy on the development and delivery of wastewater heat recovery projects for district heating applications.

Wastewater heat recovery unlocks low-carbon heating and cooling from existing sewer and wastewater infrastructure. Sewers carry large volumes of heated water from domestic, commercial and industrial use, creating a predictable, local and underused heat source that can support heat networks, district heating schemes, public estates, campuses, mixed-use developments, hospitals, universities, councils and industrial sites.

While the opportunity is significant, successful delivery depends on early coordination across specialist disciplines. By combining Colloide’s in-house process engineering, design, project management and delivery capability with Recirc Energy’s specialist wastewater heat recovery knowledge, the aim is to support a clearer and more practical route from concept through to implementation.

Recirc work in unlocking the latent heat in sewers and other wastewater sources. Its exclusive focus gives clients specialist knowledge across feasibility, design, installation and operation, supported by a portfolio of packaged systems in optimised sizes.

Recirc’s capability includes flow and temperature monitoring, sewer and wastewater energy resource assessments, heat-resource modelling against heat demand, technology appraisal, concept design, CAPEX and OPEX costing, financial modelling, RIBA Stage 2 to Stage 4 design solutions, MEICA and civil engineering, heat pump selection, integration with existing heating systems, procurement support, installation, commissioning, project management, operations, maintenance and system optimisation.

Recirc’s experience is demonstrated through a growing portfolio of UK and international wastewater heat recovery projects. This includes sewer energy surveys and heat zoning across five Greater Manchester locations for AECOM and DESNZ, feasibility and concept design for the 5 MW Trafford Civic Quarter District Heat Network scheme, and the UK’s first commercial wastewater heat recovery system at Borders College, Galashiels, which has delivered more than 6 GWh of low-carbon heat and has been owned and operated by Recirc for over 10 years. Internationally, Recirc has also provided expert peer review for a wastewater heat recovery system in Surrey, British Columbia, and acted as technical experts on the National Western Center in Denver, what will be North America’s largest operational sewer heat recovery system.

Projects can become fragmented once they leave feasibility. A successful scheme requires multiple specialist interfaces to align, including source heat extraction, hydraulic performance, heat pump integration, process design, mechanical installation, controls, civil interfaces, access, maintainability, Water Authority engagement, heat-resource modelling, screening, filtration, heat exchange, commissioning, operation and maintenance.

For ESCOs, heat network developers and project stakeholders, managing these interfaces across multiple specialist organisations can introduce complexity and delivery risk. Early engineering coordination is therefore critical, particularly as projects move from feasibility and concept design into detailed design, procurement, construction and commissioning.

Colloide can support councils, universities, hospitals and other public and private sector clients directly, while also acting as a specialist subcontractor or consortia delivery partner for larger developers in the market. As a specialist integrator, Colloide helps bring together process engineering, energy centres, heat networks, MEICA interfaces, heat pump integration, controls and practical site delivery into a coordinated project route.

With over 20 years’ specialist process engineering experience across water, wastewater and energy, Colloide supports clients’ sustainability goals by designing, delivering and maintaining resilient, scalable low-carbon heat systems. With in-house engineering, full lifecycle project delivery and proven success in integrating complex energy technologies, Colloide helps turn ambitious concepts into operational networks.

As process engineers, Colloide brings technical depth in integrating multiple technologies, including district heating networks, CHP, heat pumps, energy centres and waste heat recovery, into one efficient system. This helps ensure that every component works together effectively, reducing operational risk and supporting long-term system performance.

Colloide’s full lifecycle capability across design, build, operate and maintain helps reduce interface risk and supports smoother execution on complex schemes. Its in-house project management expertise aligns design, engineering, construction and O&M into a coordinated process, reducing the gaps and delays often caused by multiple contractors. Acting as a specialist design-and-build partner, Colloide provides clients with delivery certainty, cost predictability and reliable long-term operation.

Colloide also designs for scalability from the outset, enabling clients to expand and adapt networks in line with future growth, regulation and technology innovation. This is particularly important for heat networks, where today’s project may need to connect to future phases, new heat sources or wider local energy infrastructure.

Colloide’s experience in low-carbon heat infrastructure includes Bunhill 2 Energy Centre and Heat Network in Islington, where Colloide acted as principal contractor for the expansion of the network using waste heat from the London Underground and delivered the UK’s first containerised, stacked energy centre in central London. It also includes Viking Energy Network Jarrow, where Colloide acted as principal contractor on a River Tyne water source heat pump and energy centre scheme with integrated solar farm, and the Bloomsbury Heat and Power Network, where Colloide is supporting the replacement of legacy gas and oil systems with air source heat pumps and four rooftop energy centres.

The opportunity is not just in recovering heat from wastewater, but in engineering systems that can be delivered, operated and maintained effectively. For clients, this collaboration means specialist wastewater heat recovery expertise, proven process engineering and delivery capability, reduced interface risk, a clearer route from concept to implementation, better coordination across technical disciplines, practical understanding of live-site delivery and support for long-term reliability and performance.