Problem addressed

Energy and carbon intensity associated with the production of domestic hot water. As buildings continue to meet higher fabric requirements, domestic hot water is set to become the largest user of energy in domestic buildings and many types of non-domestic buildings with showering accounting for up to 80% of domestic hot water use in certain cases.

Solution overview

Waste Water Heat Recovery Systems (WWHRS) reduce energy and CO2 associated with production of domestic hot water, recovering up to 65% of the energy that normally remains in shower waste water and enters the drain. The recovery is achieved by means of energy exchange using a heat exchanger with all systems being completely passive, requiring no planned maintenance and having a life expectancy of >50 years. The recovered energy is used to preheat the cold water feed supplying the cold side of the shower and/or the domestic hot water (DHW) heater. The DHW load associated with showering can be reduced by over 50% when WWHRS are installed.

Cost benefit

A typical vertical WWHRS will cost between £350 – 450 per unit. In a domestic family home depending on fuel source a system can pay for itself in 2-6 years and in some non-domestic scenarios payback can be as low as 1 year.

Case study

A selection of case studies can be found here – https://recoupwwhrs.co.uk/case-studies/