In Summer 2014, CJR Midlands and SHARC Energy Systems invited Infinitas to conduct a technical feasibility study for their HNDU project. The study focused on the opportunity to deploy sewage heat recovery as a replacement for a part of the NCC-owned heat network consisting of a local leisure centre, ice arena, a student accommodation block and 244 council houses.

Our team carried out technical surveys on the leisure centre, ice arena and student block. Additionally, we conducted energy modelling for the council houses. As a result of using a mixture of half-hourly heat consumption data, monthly energy bills and EPCs/DECs, we derived:

• The peak heat demand and annual thermal profile for the more prominent buildings
• Estimated heat demand from the council houses

As a result of site surveys, we confirmed the age and condition of existing boilers and heat exchangers and the estimated demand from the council houses.

We conducted calculations to determine the potential heat capacity within the large local sewer. Our team also found the capacity in the ground. Hence, we concluded that the client needs a hybrid system comprising sewage heat recovery and open and closed-loop ground source heat pumps.

Infinitas also supported SHARC Energy Systems during the financial modelling. Once we found out the peak demand of buildings, our engineers could size and route the low-temperature heat network and site the energy centre. Then, we created high-level general arrangement drawings to size the centre and its heat plant.

We presented the final design to NCC and the Department of Energy & Climate Change (DECC). Our efforts resulted in designing a 2.2km network aiding the buildings with a 1MW heat pump system served by sewage heat recovery and an open ground loop. We also added our input to the sensitivity analysis to assess the impact of higher or lower system efficiencies and higher or lower heat demand from the properties. Based on our findings, an annual heat generation was 3.7GWh. With the region’s competitive price of 5p/kWh, payback occurred in 11.5 years.

Let’s discuss your scope of work

Would you like to have a successful ending for your project, too? Let’s talk about your scope of work and what our engineers could do to support your journey towards the green future. We aim to make heat pumps accessible, and by listening first, we will fully understand your goals and needs.