Warm cooperation Delfland Water Board and Eneco in aqua-thermal energy

The Delfland Water Board and Eneco will be working together to supply households with heat extracted from treated waste water. This way, they aim to take a new step together towards increasing the sustainability of the energy supply in the region.

Sustainable sources of heat play an important role in being able to phase out natural gas in the future, in particular in densely populated areas where the availability of sustainable sources of heat is limited. Treated waste water contains heat that is not being used as yet. This is why Eneco and the Delfland Water Board are going to apply aqua-thermal energy techniques in order to use the heat that is produced during the waste water treatment process, for heat supply purposes. Thus, we will be working together on the development of a good sustainable source of heat for the region.

Ruud Egas of the Delfland Water Board: “Delfland treats the waste water of some 1.2 million people and 35.000 companies, thus playing an important role in public health and the water quality in our region. To this end, we use four waste water treatment plants that also enable us to contribute to the energy objectives that apply for the region. At the water treatment plants, we produce green gas from the biogas that is formed during the waste water treatment process. We supply this green gas to the natural gas grid. At our sites, we also generate solar and wind energy. Extracting heat from our waste water is a splendid additional step towards increasing the sustainability of our treatment plants. Eneco is the expert partner that we need to extract the heat from the water and distribute it.”

Elmer de Boer, New Energy Development Eneco: “The cooperation with the Delfland Water Board offers interesting opportunities for accelerating the energy transition. Applying aqua-thermal energy techniques to waste water treatment plants means that we will be using local sustainable sources of heat for the heating networks in this region. The waste water flows produced by residents in the region will be reused to supply heat to these same residents. This brings us a step closer to a carbon-neutral heat supply. ”

Aqua-thermal energy as a sustainable source of heat
By means of aqua-thermal energy techniques in the form of a heat exchanger connected to a heat pump, heat is extracted from the treated waste water. This makes it possible to raise the temperature of the obtained heat (thermal input) to 75°C. Part of this is stored in a heat buffer as backup and another part is used as a source of heat for the heating network. Cold water from the network heats up and flows back into the heating network at a high temperature, thus ensuring a comfortable temperature and the availability of hot water in the homes connected to the network. Thus, the treated waste water becomes a sustainable source of heat for homes.