Retrofitting Homes: Could WWHRS be more impactful than heating controls, loft insulation, and LED lighting combined?
A recent overarching strategy report on decarbonising UK homes authored by a think-tank of independent energy-industry professionals: Thirty for 2030, clarifies the potential impact of WWHRS, as a retrofit technology for UK homes.
The report suggests that WWHRS could be more impactful than retrofitting Heating controls upgrades; Loft insulation upgrades and energy efficient lighting upgrades combined!
The figures below taken from the report, show that WWHRS, if installed to 50% of UK homes could save 7.79 TWH of energy.
WWHRS is currently used primarily by new build developers in houses, apartments, student accommodation, hotels and gyms. But it is fairly obvious that as existing homes become more insulated and thermally efficient via fabric, air-tightness and insulation upgrades, that hot water production in existing homes will dominate as the major energy user.
WWHRS can be retrofitted and works with practically any DHW source (combi, cylinder, ASHP, Solar etc) The addition of WWHRS effectively reduces how water demand, as showering is the number 1 user of hot water in the home. WWHRS installed as a primary retrofit measure helps future proof existing homes, as it can work as part of any future low carbon heating upgrades, such as heat pumps etc. In fact, including WWHRS as part of a Heat Pump system is proven to significantly improve the seasonal and overall System COP of any residential heat pump installation.
Furthermore WWHRS can be more impactful than other common retrofit measures, such as Solar thermal systems, but installed for around 80% of the cost.
Recoup Specialise in Waste Water Heat Recovery for Shower (WWHRS). This is a cost-effective energy efficiency technology that can significantly reduce hot water use in the home, by passively recycling the waste heat energy that goes down the drain when showering.
The Recoup Easyfit+ is an ideal retrofit WWHRS choice. It locates in the unused void-space under a standard bath, connecting to the shower mixer above. It can be installed by any competent plumber, or even a DIY project for an energy conscious homeowner.
The regulation states that any fluid of category 4 or 5 must be separated by a double wall in order to comply. It is generally accepted (but debateable) that the change of fluid category associated with showering is at the point of the trap for the shower where it passes from its lowest possible category of 3 to a category 5 fluid on joining the rest of the waste system. There are certainly some circumstances where the shower waste itself prior to the trap may be deemed as a category 5 fluid.
Therefore, in order for a single walled product to comply, additional design and installation requirements are required.
The primary implication of this it that a drainage trap must be installed downstream of the unit, and therefore a trap should not be installed before the WWHRS. Removing the trap from the normal position at the bath or shower tray, and then relocating it downstream of the WWHRS unit (often on the floor below the shower or bathroom), can present several significant issues to both the installer and homeowner:
Recoup WWHRS Learning is our online education portal for all things waste water heat recovery. Made up of courses containing lessons and quizzes it goes from an introduction to waste water heat recovery for showers to product installation courses. Find out more here.