Integrating existing water and wastewater assets to reduce domestic heating emissions

A study was undertaken to explore opportunities for achieving reducing greenhouse gas emissions from UK domestic heating by using existing drinking water and wastewater assets as energy storage and recovery mechanisms, coupled with modest local renewable energy generation. The sensitivity of the solutions to future projections for domestic heating demands and climate change effects was explored. Simulations optimised the available energy supply, potential for storage, heat recovery and heat demand to minimise emissions at a scale that could be adopted in most UK towns. The approach may be able to deliver significant emissions reductions with more limited capital investment than more centralised renewable energy approaches. Results from two UK locations showed that integrated water–energy systems could theoretically reduce emissions by about 50%. Furthermore, the system could satisfy demand for about 70% of the time periods each year. Future scenarios were tested and it was found that the projected annual emissions reduction was similar across all scenarios, suggesting this would be a robust approach.