1) ATES (Aquifer Thermal Energy Storage) is a reliable geothermal energy technology that uses underground aquifers to store thermal energy from cooling and heating systems. 2) For ATES to be reliable, it is important to use proven technology implemented by experts, have a total energy concept that balances the system, and involve specialists throughout the project phases. 3) Potential reliability issues can be avoided by using redundant systems, high quality components, monitoring, and tailoring the system to local geological conditions.

1. Reliable ATES systems
ing. Marcel Swets eur.ing. (CTO)
IF Technology
April 3rd, 2012

2. ATES = Aquifer Thermal Energy System
 Principle Dutch style ATES, characteristics:
o Closed system
 100 % extraction = 100% injection (= no loss of ground water)
 air tight, over pressure (= no chemical disorder)
o Using the outside air temperature (seasons)
o Using the natural underground water layers (aquifer)

3. ATES - schematic

4. ATES - in the Netherlands
 Since 1989, commercial IF Technology (IF) projects
 IF: over 20 years experiences and over 1,300 projects
IF ATES projects in the Netherlands approx. 50 IF ATES projects in and around Amsterdam

5. ATES – system set up
 Well doublet: a pair of 1 warm well
and 1 accompanying cold well
 Entire ATES system with circuit temperature sensor
PT
TT
heat exchanger
FT
TT circuit flowsensor
circuit pressure sensor
PT
several separated doublet systems LT
injection valve level sensor
LT
submersible pump
cold well
(coupled in cooling system)
warm well
TT
heat exchanger TT circuit flowsensor
circuit temperature sensor
FT circuit pressure sensor
PT PT
injection valve level sensor
LT LT
submersible pump
cold well warm well
TT
heat exchanger TT circuit flowsensor
circuit temperature sensor
FT circuit pressure sensor
PT PT
injection valve level sensor
LT LT
submersible pump
cold well warm well

6. Reliability of ATES
 ATES = proven technology -> implemented by experts
 Important conditions:
o Total energy concept (integral system)
 Energy / load values
 Energy balance
– Cooling system = Master
– ATES = Slave
o Support of specialists during all phases of project
 Design, construction phase, permits, etc.…

7. Reliability of ATES
 Problems/failures:
o Trap: ATES looks like very simple; it is not
o No real experts/professionals involved
 Engineering
 Construction
 Maintenance
 Permits
-> Using different (lower quality) standards
-> Not as a result of energy concept and/or ATES

8. Legislation and regulations
 Groundwater authority: Province
 Water act (WaterWet)
o Protected area (eg geological monument)
o Ground water protection zone (eg drinking water)
o Site survey
 Nature, sensitive area
 Interferences, pollution
 Municipality
 Water board

9. ATES systems
 Key words
o Robust
o Reliable
o Safe/protected
-> Just technical solutions !
o Engineering
o (innovative) thinking
o Points of attention

10. ATES points of attention (1)
 Redundancy
 Hydraulic effects
 Interference
 Routing in terrain
 Split system
 (n+1)
 Anticipate/discuss requirements of client & system

11. ATES points of attention (2)
 Proven ATES components
o MTBF
o MTBR
 Use high (not standard) quality and design standards
 Safeguards
 Data loggers /system monitoring
 Energy efficient components (electrical and thermal)

12. ATES points of attention (3)
 Quick response / start up
 Tailor made system
o Amsterdam:
 High water table
 Artesian water
 Drilling
 Telescopic well head

13. Summary
 ATES is reliable when:
o Use reliable and professional partners
 Consultants
 Contractors
 Suppliers
o Project organization & clear roles
o During all project phases

14. Fairy tales
 The deep underground is a mystery
 Flow capacity is not guaranteed
 Wells are clogging
 Drilling depths is uncertain
 Bursting of soil layers
 ….

15. Thank you for
your attention
m.swets@iftechnology.nl