On behalf of the TU Delft I participated during the past 5 years in a climate-KIC project, to identify and solve barriers for Aquifer Thermal Energy Storage (ATES) adoption in Europe. After identifying the most important barriers for, mature and immature ATES markets, we proposed solutions for those barriers and tested them at various sites across Europe. Now the project is ending we did a roadshow along some of the pilots to present the results at local events.
1st trip to Spain: technology to work round a legal barrier
The barrier in Spain is a legislation barrier: it is not allowed to re-inject extracted groundwater, hence making ATES impossible. Itecon (Julian Rodriguez) and ITC (Alicia Andreu) developed a new type of Geothermal system which is a combination of an open and a closed loop system. Several closed loop U-tubes are installed in a borehole with a screen at the bottom and at the top. Groundwater is pumped from one screen to the other along the tubes in the borehole, strongly increasing the heat exchange of the closed loop tubes and not extracting groundwater. This system is installed at the municipality swimming pool of the town of Nules, close to Valencia. In October we visited the site and presented the results of all the pilots at a conference at ITC.
2nd event in Italy: ATES in areas with high groundwater flow
The Barrier at the Italian Pilot site is the presence of high groundwater flow and lack of experience with the technology. Terna is a power plant which distributes electricity over the country. Marco Pellegrini from University of bologna and Sara Picone from Aster ran this pilot. As a result of the groundwater flow the system was designed as a recirculation system. This ATES system was the first of the local authority to issue a permit for.
In Italy we also visited and presented the results of the project at ECOMONDO in Rimini. During the session at ECOMONDO, the results of each pilots was presented. At ECOMONDO I presented about the working principle of ATES and how to accommodate many ATES systems, and about the Delft pilot.
Final Stop: Delft. PVT panels to get heat and power
At the Deltares campus in Delft an existing ATES system is equipped with Photo voltatic and thermal energy (PVT) panels to gain extra heat, to supply to the associated buildings and run the heat pump on solar power. The combination of ATES and PVT cells was made to overcome the heating imbalance that often occurs in ATES systems. At the Deltares campus in Delft, the ‘Virtu’ PVT cells of Naked Energy (Adrian Murell, Nick Simmons) were connected with the ATES system present there.
The pilot sites I did not visit
Denmark and Utrecht: on the combination of ATES and bioremediation. Combining ATES systems with bioremediation could help to overcome an important barrier for the implementation of ATES systems; i.e. the presence of groundwater pollution. Run by Deltares (Nanne Hoekstra, Sophie Monier, Gemma Spaak) and WUR (Tim Grotenhuis).
Belgium: also PVT in combination with ATES is installed at the Nike distribution centre in Ham, they also had a successful event, but I did not visit it myself. Run by Deltares and Arcadis (Hendrik Jan Steeman).
Final meeting and conclusions
December 12th, the day after the visit in Delft we had the closing meeting with Climate-KIC in Utrecht. In Utrecht we presented the work done, main conclusions and possible follow-up.
Climate-KIC is very happy with the obtained results, now we’ll focus on the final reporting!
- While running an ATES system, the focus should be on performance. This is a continuous optimization process, this is different from conventional techniques where only installation is important. Adding technologies like PVT (in case of heat shortage) help to increase performance.
- (Extensive) monitoring is needed to obtain permit for first project, together with conclusive research on the WQ effects these result should give authorities the confidence to minimize required monitoring and adopt ATES legislation.
- Soil contamination is not necessarily a showstopper for ATES, but successful biodegradation depends on many local conditions. it may take a while to identify the optimal working conditions for biodegradation
- Promote ATES by enforcing level of energy performance/emission of buildings, this will also help for contractors to see business opportunities for ATES
- Keep promoting and sharing successes, public awareness is not achieved with one research project.
- Analysis of ATES effect on GWQ for local conditions in different countries for authorities to adopt more flexible legislation à uniform specific legislation
- Explore possibilities of heat storage at higher temperatures
- Separation of knowledge and skills in the supply chain for ATES implementation and realization à focus on optimization/operation of ATES