Substantial energy savings thanks to aquifer thermal energy storage loop at Wageningen Campus

October 26, 2020

Wageningen University & Research (WUR) aims to make optimal use of an aquifer thermal energy storage (ATES) beneath Wageningen Campus. For this reason, an ATES loop is currently under construction and buildings are being customised. This move will generate significant sustainability benefits: when it comes to heating buildings, the measures are expected to deliver a 95% reduction in natural gas consumption; a 63% reduction in gas-related CO2 emissions is also expected.

Where possible, all central heating boilers will eventually be replaced by heat pumps. The construction of an ATES loop and the planned changes to the buildings are in accordance with the Association of Universities in the Netherlands’ (VSNU) Climate Agreement for 2030. The modifications also fit in with WUR’s Energy Vision for 2030, in addition to other transitional measures like insulation and LED lighting. The ultimate goal is to achieve a campus that is completely free of natural gas. The entire project must be completed by July 2021.

What is the purpose of an ATES loop?

WUR’s Energy Transition Plan is based on two principles: energy savings and energy generation. WUR currently achieves the latter through the use of such devices as solar panels and wind turbines. A ATES primarily pertains to the first principle. It saves energy (natural gas and therefore CO2 emissions) by temporarily storing the excess heat underground and pumping it up again when required. And by pumping cold water up to cool the buildings, money can therefore be saved on electricity bills. This is the reason why the Orion and Helix buildings, for example, are now almost completely free of natural gas. Separate sources are required for both streams. These have now been linked together via a loop.

Differences between the climate requirements

Many buildings on the campus are already making partial use of an ATES. However, there are vast differences between the climate requirements of the buildings and usage areas. For example, consider the difference between a greenhouse and an office, or a laboratory and an educational building. Heating and cooling requirements also depend heavily on the weather.

For individual buildings that have their own ATES sources, maintaining the balance between the heating and cooling requirements is a major challenge. One efficient solution would involve one loop for both streams, which would connect all of the buildings on campus. An ATES loop allows buildings to make more efficient use of each other’s surpluses and shortages.

Initial drilling has begun

Heijmans construction company has already started work. The capacity of twelve existing heat and cold sources will be increased for the purpose of the ATES loop. Six new sources will also be drilled. The loop will be constructed via horizontal directional drilling and so-called ‘open excavation’. The horizontal directional drilling method offers the advantage of having minimal impact on the environment. The first heat source, which is no less than 90 meters deep, is now a reality. The entire project must be completed by July 2021.