Figures collected by the European Association for Wastewater Heat Recovery (EuroWWHR) indicate unprecedented growth of 48% in 2022 in annual sales of wastewater heat recovery units manufactured in Europe for residential applications.
Wastewater Heat Recovery (WWHR) is an available and effective energy efficiency solution to reduce the energy demand for domestic hot water via the direct heat recovery from shower drains. A specifically engineered heat exchanger transfers waste heat energy from the waste hot shower water to the incoming fresh water supply, warming it from around 10 up to 25°C.
Considering up to 80 percent of hot water is used in showers, harvesting heat from shower drains in buildings is a simple and cost-effective way to save around 40 percent of final energy and related CO2 emissions of hot water production.
WWHR systems are developed and manufactured by innovative European SMEs. Ten companies, members of EuroWWHR, reported annual sales of 26,035 individual residential units in 2022, representing 48% growth vs. 2021 when 17,644 units were sold. In addition to individual, residential application, 107 collective units were sold in 2022. Collective units are deployed both in residential and non-residential sectors in multifamily apartments and e.g. swimming pools.
Individual and collective WWHR units manufactured in 2022 in Europe deliver annual energy saving of around 20 GWh. This avoided energy use can fully cover hot water demand of nearly 14.5 thousand European dwellings.
Future potential is much higher: according to study by University of Innsbruck and Passive House Institute[1], if between 2022 and 2030, every second renovated or newly constructed building in Europe were equipped with the WWHR system, 35.7 TWh less energy would have to be generated and 6,6 Megatons of CO2e emissions less emitted.
This enormous energy saving potential can be easily unlocked by amending Energy Performance of Buildings Directive (EPBD) Annex 1, with the addition of heat recovery characteristics to the aspects to be considered in calculation methodology (point 4), and to ensure that heat recovery is considered in the planning and optimization of hot water systems all over Europe.
Hugo Durou, President of the EuroWWHR said: “2022 was an outstanding year for European wastewater heat recovery unit sales. The foundation is laid for continued exceptional growth and we believe that ongoing EPBD recast will unlock the energy saving potential of WWHR systems in line with the Energy Efficiency First principle. Considering current energy prices/security crisis in Europe, ambitious requirements for the energy performance of buildings are crucial to sustainably reduce energy bills and alleviate energy poverty, will accelerate the decarbonisation of the EU building stock and are critical pillars of the Fit-For-55 package.”
European Association for Wastewater Heat Recovery https://www.eurowwhr.eu/
[1] The potential of Wastewater Heat Recovery Systems in reducing the energy need for water heating in the EU in a cost-efficient way, Study, University of Innsbruck, Passive House Institute, March 2022