Dutch Urk seafood companies test water-source cooling system, 18 companies interested in waste-heat utilisation

Seafood companies in Urk, the Netherlands, are preparing for a water-source cooling system. On Tuesday 1 September, Van der Lee Seafish demonstrated in a trial how water cooling can reduce the energy consumption of refrigeration systems and heating systems. Company director Willem van der Lee called it a "win-win situation": using low-temperature cooling water can lower companies' energy costs, while the warmed cooling water can greatly reduce households' energy costs.

The trial is part of a complete renewal of Van der Lee Seafish's refrigeration facilities. To comply with regulations under which so-called F-gases are no longer permitted, the company has replaced its entire refrigeration installation with a system using carbon dioxide as refrigerant, used to maintain low temperatures in two freezer stores, the fresh-fish freezing installation and three spiral freezers; the whole installation contains eighteen compressors in total.

Under current practice, drinking water is needed in summer for supplementary cooling of the installation, and expensive chemicals must be used to prevent scaling and legionella. With cooling by groundwater-source water, this drinking water no longer needs to be topped up — according to Van der Lee, this drinking water is lost through evaporation. In his presentation he said that with the system, the heat released or added to the cooling water can in principle be extracted again elsewhere, for example via a central heat pump in a district heating network or a company's own heat pump.

In the trial, Van der Lee Seafish filled a loading dock with water and cooled it to 11 degrees Celsius, comparable to the cold-source temperature, and then used this water to cool the compressors; energy consumption was already better than calculated in advance.

Before the system can actually go into operation, wells still need to be drilled for hot and cold storage. Marten Poelman, who is involved in the project on behalf of the Urk fish traders' and processors' association, said permits have been granted, but the municipality wants to wait a while longer. The existing plan is to build seven clusters with associated water sources in the existing industrial area, with the clusters spaced far enough apart that cold and heat do not affect each other. Eighteen companies have already expressed willingness to take part, but the energy cooperative currently starts with only three companies that want to receive cooling water supply: Van der Lee Seafish, Kramer Fish and Diepvries Urk; other companies can join later.

The system can supply the warmed cooling water to households in the existing built-up area of Urk. For new residential areas, Urk has chosen Energienet Urk, which wants to obtain heat from the new industrial area Port of Urk. However, construction by heat supplier Americold in that industrial area remains uncertain. As a result, alderman Tunis Hoekstra does not rule out that new residential areas will also use the warmed cooling water supplied by the energy cooperative.