Energy consumption from 1996 (and before) to 2011: The installation of a heat recovery plant in the laboratory building in Dübendorf and a lake water source heat pump in Kastanienbaum in 1997-1998, together with other measures, secured a reduction in energy consumption for heating from 9 TJ per year down to less than 5 TJ. Electricity consumption by Eawag as a whole has continued to rise.
Energy measures implemented in the buildings enabled us to reduce energy consumption for heating and cooling to a very low level. Thanks to the installation of a heat recovery plant in the laboratory building, heating energy consumption was reduced there from 4 TJ to 1.5 TJ in 1998. With the renovation of the laboratory building in 2009, heat recovery was further improved by a substantial amount. At the beginning of 2008 the rented, gas-heated Chriesbach property in Dübendorf was vacated. It was replaced by Forum Chriesbach – a new build that complied with sustainable development criteria. The expansion of the old office building and retro-fitting of energy efficiency features were completed by the end of 2007.
At the Dübendorf site, Eawag draws most of its heating energy from the Empa heating plant. Around 25% of this heat comes from waste heat (heat pumps), while the remainder comes from a gas heating plant which replaced the former mixed gas and fuel plant. The switch to a new technology with higher efficiency and lower CO2 consumption is currently underway.
The research centre for limnology in Kastanienbaum has been heated by means of a lake water source heat pump since 1997, at which time the fuel consumption was reduced from 1TJ to just 0.1 TJ. The boathouse was renovated in 2007. In 2010, portable office cabins were replaced with a Minergie-P wooden pavilion – the first of its kind in Switzerland. The lake research centre was renovated from 2011 to 2013, resulting in improved energy consumption here also.