Water-Saving Products for Greater Energy Efficiency
Study Commissioned by the Hansgrohe Group Analyzes Energy-Saving Potential in Residential Buildings
Schiltach, August 2024. How can the energy efficiency of buildings be improved to achieve climate neutrality? The answer so far has been: through climate-friendly heating, even more thermal insulation and energy-saving behavior on the part of building occupants. A study initiated by the Hansgrohe Group has revealed another significant energy-saving lever: efficiency technologies for hot water consumption. "Our calculations show that the total energy requirement can be reduced by up to six percent through the use of water-saving and energy-efficient technologies in showers and faucets. If drinking water is heated using decentralized instantaneous water heaters, the savings potential even increases to up to 12 percent," says study author Professor Bert Oschatz from the Institute of Technical Building Services, ITG Dresden. According to the study, adapting standards and laws could harness the potential of these technologies to achieve environmental goals and ensure a sustainable and secure energy supply.
Potential savings in domestic hot water for single-family homes
In fact, millions of liters of hot water flow through residential buildings every day. According to the German Energy Agency's (dena) Building Report 2024, as much as 16 percent of the final energy consumption of these buildings is used to heat water. This makes it the second highest energy consumer in residential buildings after spatial heating. There is potential for savings here that can be better exploited. This was the result of a study commissioned by Hansgrohe from dena in Berlin at the beginning of this year. Conducted by the Institute for Technical Building Services, ITG Dresden, the study determined the energy-saving potential for single-family homes. The core result: the installation of water-saving faucets and shower heads alone could reduce primary energy demand and total greenhouse gas emissions of buildings by two percent in existing buildings and by six percent in new buildings; in combination with decentralized water heating, by up to twelve percent. Future studies could help to identify further potential energy savings along the drinking water supply inside and outside the building by reducing hot water consumption.
Basis of the Study
ITG Dresden looked at three generations of single-family homes to investigate the energy-saving potential of water-saving bathroom products: Existing buildings from the 1990s, reference buildings with thermal insulation in accordance with the Building Energy Act (GEG) and efficiency houses with a primary energy requirement of just 40 percent. The experts quantified the potential energy savings for all three building categories in accordance with the DIN V 18599 standard. The savings potential for buildings with an already very low heating requirement is particularly high in relative terms. For the study, the institute looked at bathrooms with and without water-saving fittings and showers and, in the latter case, also differentiated between bathrooms with a high proportion of showers or baths.
Results Reveal Need for Action
Fiona Félix, Head of Public Affairs at Hansgrohe SE, sees a need for further action based on the study: "Saving hot water can make a significant contribution to the energy efficiency of buildings. For these climate-relevant effects to be realized, more awareness of the hot water factor is needed, including among architects, construction project developers and building owners. The implementation of the European Directive on Energy Efficiency in Buildings therefore offers legislators a good opportunity to take the energy requirement for hot water consumption into account when calculating the energy requirement certificate and when drawing up the individual renovation roadmap." In addition, the Hansgrohe Group recommends including the consumption of hot water in the standards for energy-efficient buildings in future. "We invite our partners from business, politics and society to a constructive exchange. If we want to achieve the goal of climate neutrality by 2045 for the building sector as well, we must work together to optimize resource consumption," says Fiona Félix, emphasizing the need for action.
Responsible Use of Hot Water
As a leading manufacturer of faucets, showers and shower systems that sells its products in over 150 countries around the world, the Hansgrohe Group is not only responsible for the climate impact of its products, but also has a major indirect influence on hot water consumption in buildings. Even today, technological innovations from the sanitary company from the Black Forest play a role in the careful use of valuable resources in everyday life, and, especially, in the bathroom. Hand-held showers with the hansgrohe EcoSmart technology use just six liters of water per minute at three bar compared to conventional hansgrohe showers with a water consumption of 15 liters per minute. In the in-house spray laboratory in Schiltach, experts develop spray types such as the micro-fine PowderRain, which ensures great showering pleasure despite the low water flow. High-quality thermostats such as hansgrohe ShowerSelect Comfort allow easy control to quickly reach the desired temperature and always keep the water temperature and volume constant so that not a single liter of water is wasted. Clever technologies not only optimize use in the shower, but also at the washbasin. The hansgrohe CoolStart technology in faucets ensures that cold water flows automatically when the handle is in the middle position. This means that energy is not used unnecessarily for heating water when the faucet is switched on and off briefly, for example when wetting a toothbrush. The integrated EcoSmart technology of many hansgrohe faucets also reduces water consumption to just four liters per minute at three bar. As part of its consistent sustainability strategy, Hansgrohe's ambition is to equip all water-bearing products from its AXOR and hansgrohe brands with water and energy-saving technologies by 2030.
"The study by dena and ITG Dresden proves that innovations in the bathroom make a significant contribution to reducing water and energy consumption," says Hans Jürgen Kalmbach, Chairman of the Executive Board of Hansgrohe SE. "Without hot water-saving technologies, there will be no energy-efficient buildings. We urgently need to rethink the way we use hot water. For us as a manufacturer of water-bearing products, the study is an incentive for further innovations for the responsible use of water and energy. If the political course is set accordingly, we can make considerable progress with our innovative strength."
The study on the energy-saving potential of water-saving showers and faucets and a factsheet summarizing the results are published on the website of the German Energy Agency at: https://www.gebaeudeforum.de/service/downloads.
About the German Energy Agency (dena)
The German Energy Agency (dena) is a competence center for applied energy transition and climate protection. dena looks at the challenges of a climate-neutral society and supports the German government in achieving its energy and climate policy goals. Since it was founded in 2000, the agency has been developing solutions, putting them into practice and bringing together partners from politics, business, science and all parts of society - both nationally and internationally. dena is a project company and a federally owned public enterprise. The shareholders of dena are the Federal Government and dena itself.
About the Hansgrohe Group – Setting the Beat of Water. Since 1901.
With its brands AXOR and hansgrohe, the Hansgrohe Group, based in Schiltach/Southern Germany, enjoys a reputation as a leader in innovation, design and quality within the bath and kitchen industry. Founded in 1901 in the Black Forest, the company gives water form and function with its faucets, showerheads and shower systems. In combination with sanitary ceramics and bathroom furniture, the company offers individual design options from a single source for holistic bathroom experiences. The 123-year history of the company is marked by innovations, such as the first hand-held shower with multiple spray types, the first pull-out kitchen faucet, and the first wall bar to hold a hand-held shower.The company holds more than 20,000 active property rights. The Hansgrohe Group stands for long-lasting quality products and for responsibility towards people and the environment. Sustainable production of resource-conserving products is central to the company’s business activities around the globe. By developing innovative technologies for faucets and showers, Hansgrohe achieves the greatest possible effect on protecting water as a resource and limiting and adapting to climate change during the usage phase of its products. As part of its consistent sustainability strategy, Hansgrohe is equipping all water-bearing products exclusively with water-saving technologies by 2030 within its "ECO 2030" initiative. With 35 subsidiaries and 21 sales offices supplying products in more than 150 countries, the globally active company in the sanitary industry is a reliable partner to its customers in all regions of the world. The Hansgrohe Group, its brands and products have won numerous awards, including more than 700 design prizes since 1974. The products of the Hansgrohe Group are found around the world: on renowned cruise ships, in luxurious 5-star and boutique hotels, in international metropolitan cities, in extraordinary spas, exclusive bathrooms of lodges and luxury villas, public facilities, as well as in countless private homes. The Hansgrohe Group’s high quality standards are ensured by eight wholly-owned production facilities: four in Germany, one each in France, in Serbia, the United States and China. In 2023, the Hansgrohe Group generated a turnover of EUR 1.406 billion. It employs around 5,400 people worldwide, about 60 percent of whom work in Germany.