Studying opportunities for energy from surface water

Producing thermal energy from surface water is sustainable and it can enhance water quality. On behalf of the Ministry of Infrastructure & the Environment, Deltares and IF Technology are mapping out the opportunities for obtaining energy from surface water in the Netherlands. The technology is available for producing energy from surface water and for establishing the link with existing aquifer thermal energy systems, but it is still only being used to a limited extent. Furthermore, energy production from surface water can improve water quality. Heat is removed from the water in the summer, reducing the risk of algal blooms and botulism. Because the technology removes cold from the system in the winter, it can help to keep waterways navigable.

In response to building cooling requirements (koude vraag), cooling water it is first cooled down drastically in the aquifer thermal energy plant and then warmed up slightly using surface water. The net effect is that heat from surface water is stored below the surface in the summer with heat-exchange units so that it can be used in the winter.

Opportunities Map

Deltares and IF Technology conducted a review based on, among other things, the Delta Model to determine how much heat and cold can be extracted from surface water in the Netherlands. These data are combined with demand for heat and cold in the vicinity of surface waters, and the presence of aquifer thermal energy plants (using www.wkotool.nl). The result is an opportunities map that makes it possible to see at a glance where using energy from surface water has meaningful potential. The map will be published in the course of 2015 and be available in time in a clickable digital edition.

In most of the Netherlands, over 75% of the cooling demand can be met using surface water and underground storage since there is adequate subsurface capacity

Affordable alternative

The researchers also carried out a life-cycle cost calculation for the use of this technology. It showed that, based on the entire life cycle, using energy from surface water is more profitable than dry coolers and solar collectors. Using the data from the research, Rijkswaterstaat can help users to obtain energy from the main water bodies in the Netherlands. The research also provides suggestions for water authorities about how to use energy from surface water as part of the Green Deal smart polder concept.