Shower heat exchanger: reuse of energy from heated drinking water for CO<sub>2</sub> reduction

Abstract

The heating of drinking water in households contributes significantly to the emission of greenhouse gases. As a water utility aiming to operate at a climate neutral level by 2020, Waternet needs to reduce its CO 2 emission by 53 kton yr −1 . To contribute to this ambition, a pilot project was carried out in Uilenstede, Amstelveen, the Netherlands, to recover the shower heat energy with a shower heat exchanger from Dutch Solar Systems. An experimental setup was built in the Waternet laboratory to evaluate the claimed efficiencies. The energy recovery efficiency observed in the lab was 61-64 % under winter conditions and 57-62 % under summer conditions, while the energy recovery efficiency observed in Uilenstede was 57 % in December 2014. Based on the observations, 4 % of the total energy consumption of households in Amsterdam (electricity and gas) can be recovered with a shower heat exchanger installed in all households in Amsterdam, which also means a 54 kton year −1 CO 2 emission reduction can be achieved.

Thermal energy recovery from chlorinated drinking water distribution systems: Effect on chlorine and microbial water and biofilm characteristics

“…In many European countries, groundwater plays a role in the underground thermal energy storage systems and is widely used at full scale (Sanner et al, 2003). In the urban water cycle, heat recovery from wastewater via heat exchangers has been intensively studied (Elias Maxil, 2015;Elías-Maxil et al, 2014), and shower water has also been applied for heat recovery from wastewater in a pilot study (Deng et al, 2016). Recently, the concept of thermal energy recovery from drinking water has been proposed, and researchers have proven its possibility (Bloemendal et al, 2015) and explored the potential technologies in practical use (De Pasquale et al, https://doi.org/10.1016/j.envres.2020.109655 Received 23 March 2020; Received in revised form 9 April 2020; Accepted 8 May 2020 2017; Guo and Hendel, 2018;van der Hoek et al, 2018).…”