1. Shallow Geothermal Energy for Heating and Cooling of larger buildings in commerce, offices, tourism Dr. Burkhard Sanner VDI, Giessen, Germany

2. Laying the ground: - Some statistics on GSHP in Germany - German standards and guidelines for GSHP Heating and Cooling with GSHP: - Principle and development - Various smaller examples - Example Leica Wetzlar (BHE) - Example Bonner Bogen (wells) Conclusions

3. Total number of installed, operational ground-source heat pumps
Calculated after data of BWP

4. Avoided CO2-emissions thanks to ground-source heat pumps
Calculated after data of BWP

5. Europe, installed capacity per country as of 2013
From EGEC Market Report 2013/14, update

6. Annual sales of ground-source heat pumps since 1978 and some events influencing this development
After data of BWP

7. Annual sales of ground-source and air-source heat pumps
After data of BWP

8. DIN EN 15450 (2007-12): “Heating systems in buildings - Design of heat pump heating systems”
(German adaptation of EN 15450)
EN elucidates the basic problem for a geothermal standard on a European level, i.e. the variations in climate, geology, traditions in construction.
As a result, it can only give a general minimum framework for design and installation, with many items to be filled in locally or regionally

9. DIN 8901 ( ): “Refrigeration systems and heat pumps – protection of soil, ground and surface water”
Deals with safety aspects of the heat pumps, in particular for use with groundwater as heat source/sink, and for direct expansion ground coils

10. VDI 4640 „Thermal Use of the Underground“:
Part 1: General Issues / Licenses / Environment, revised (draft published 1998, original )
Part 2: Ground Source Heat Pumps, (original draft published 1998, draft of revised text )
Part 3: Underground Thermal Energy Storage (UTES), (revision ongoing)
Part 4: Direct uses, (revision started)
Part 5: Thermal Response Test, draft expected fall 2015
Covers all relevant aspects in very comprehensive way
Started in 1995 following an initiative from the geothermal sector
Elevated shallow geothermal from scratchbuilding to industrial product !

11. VDI , draft
groundwater wells as heat source/sink
horizontal ground collectors
borehole heat exchangers (incl. heat pipes)
special issues for direct expansion systems
other ground heat exchange devices (energy piles and concrete parts, tunnel walls, compact ground collectors)
system integration
issues related to the heating system
materials for ground heat exchange devices
measures in case of system failure, de-installation

12. Chapter 7 on borehole heat exchangers, systems <30 kW
VDI , draft
Chapter 7 on borehole heat exchangers, systems <30 kW
Basic load profile for tables on specific heat extraction

13. Chapter 7 on borehole heat exchangers, systems <30 kW
VDI , draft
Chapter 7 on borehole heat exchangers, systems <30 kW
Target temperature values and formula for tables on specific heat extraction
Minimum temperature from heat pump:
for base load ≥ 0 °C
for peak load, three scenarios: ≥ -5 °C, ≥ -3 °C, ≥ 0 °C
Maximum temperature from heat pump / system:
- in cooling mode ≤ 20 °C

14. Chapter 7 on borehole heat exchangers, systems <30 kW
VDI , draft
Chapter 7 on borehole heat exchangers, systems <30 kW
Example of tables on specific heat extraction

15. Chapter 7 on borehole heat exchangers, systems >30 kW
VDI , draft
Chapter 7 on borehole heat exchangers, systems >30 kW
Individual calculations or simulations are required
Possible methods:
analytical solutions (heat transfer calculation)
nomograms or simplified calculation methods
simulations using approximative functions
numerical simulations

16. DVGW (German Water and Gas association) guidelines for certification of drilling companies:
DVGW W120-1 „Qualification requirements for drilling technology, well construction, rehabilitation and de-installation“,
DVGW W120-2 „Qualification requirements for drilling technology and shallow geothermal energy (borehole heat exchangers)“,
These guidelines set the requirements in equipment and skilled personal for certification of drilling companies
Virtually all construction licenses for shallow geothermal installations in Germany require the drilling company to be certified

17. While heating demand will decrease in the EU, cooling demand is expected to increase further
Graph from the Common Vision of the RHC-Plat-form, 2011

18. Cooling in shallow geothermal installations can be achieved in different ways:
Running the heat pump as cooling machine (either by changing refrigerant flow or by external hydraulics)
Using the ground directly for cooling (as long as supply temperatures from the ground are low enough)
Combination of the two methods mentioned above
Dedicate cold storage in the ground (lowering the ground temperature in winter intentionally, e.g. by air coolers)

19. Already an early (probably the first) GSHP in the USA used heating and cooling, Indianapolis, 1945
Heat source and –sink:
- horizontal coils in trenches
- direct expansion
Winter, heating
Figure from Crandall (1946)

20. Already an early (probably the first) GSHP in the USA used heating and cooling, Indianapolis, 1945
Heat source and –sink:
- horizontal coils in trenches
- direct expansion
Summer, cooling
Figure from Crandall (1946)

21. First practical application of direct cooling from the ground in Europe, using closed-loop BHE, at Helmut Hund GmbH, Wetzlar, 1987
Figure published at IEA Heat Pump Conference Tokyo (from Sanner , 1990)
Winter, heating
Summer, cooling

22. Small optical factory with cooling of dust-free rooms (almost all year round) in Rathenow, 1992
Figure from Sanner (1993)

23. Office building VIKA in Aachen, 2003
28 BHE each 43 m deep
Heating and cooling through pipes in floor/ceiling slabs
Very well suited for direct cooling from the ground
Graph and photos VIKA / EWS

24. Heating and cooling with GSHP works far North:
Location: 65°51’ N
Heating and cooling with GSHP works far North:
Hotel Storforsen in Bredsel, Älvsbyn, Sweden
33 BHE each 160 m deep
Hotel Storforsen on the Pite river (Piteälv)

25. Heating and cooling with GSHP works far North:
Location: 65°51’ N
Heating and cooling with GSHP works far North:
Hotel Storforsen in Bredsel, Älvsbyn, Sweden

26. Heating and cooling with GSHP also works in the South:
Location: 37°40’ N
Heating and cooling with GSHP also works in the South:
European Centre for Public Law in Legrena, Lavrio, Greece
(built in the frame of Thermie-project MEDUCA in 1999/2000)
2 groundwater heat pumps (80 and 120 kW) with production and injection well, yield up to 25 m3/h
Photo: CRES
Photo: Google

27. Further successful (non-residential) applications in Germany
convention centre
factory
logistics facility
railway station
shopping mall
supermarket
town hall
…and many more

28. New headquarters of Leica AG, Wetzlar (inaugurated May 2014)
Photo: UBeG

29. New headquarters of Leica AG, Wetzlar
Located in a former military area, now converted into a business- and science-park
Already other BHE systems in same area

30. New headquarters of Leica AG, Wetzlar
Total of 80 BHE each 120 m deep in two fields
Very complex energy system, including heat pump, CHP, peak boiler, absorption chiller, etc.
FEFLOW- modeling to determine temperature distribution in the field and prove their is not interaction of the fields (figure: UBeG)
Simplified schematic of the energy system

31. New headquarters of Leica AG, Wetzlar
Drilling with 3 rigs simultaneously (February 2012)
Finished BHE field before connecting (March 2012)
Photos: UBeG

32. 2009 2004 Reclamation of a former industrial site:
Photo and graph: BonnVisio - Bonner Bogen
Reclamation of a former industrial site:
- 5-star-plus hotel “Kameha Grand”
- Several blocks of offices
- Location on banks of river Rhine
- Preservation of some landmark elements from former buildings
First, smaller GSHP project in 2004
Second, much larger stage in 2009

33. Groundwater heat pump system based on 6 wells
Photos and graphs: UBeG GbR / BonnVisio - Bonner Bogen
Groundwater heat pump system based on 6 wells

34. Final well diameter Ø 800 mm
Photos and graphs: UBeG GbR / BonnVisio - Bonner Bogen
Final well diameter Ø 800 mm
Groundwater heat pump system based on 6 wells

35. Photos and graphs: UBeG GbR / BonnVisio - Bonner Bogen
neighbour
Large groundwater heat pump system require numerical simulation for design
In the sample case, influence of varying groundwater level, and interaction with river Rhine and with neighbouring plants had to be checked
neighbour
2009
2004
River Rhine

36. The groundwater system provides ca 1 MW of heat and cold as baseload
Photos and graphs: UBeG GbR / BonnVisio - Bonner Bogen
The groundwater system provides ca 1 MW of heat and cold as baseload
well 8

37. Shallow Geothermal Cooling can save energy
Shallow Geothermal Cooling can save energy ! Highest efficiency is with direct cooling: - Only possible in moderate climates, not too humid - Cooling-SPF in the order of is possible Cooling using heat pump as chiller can be done everywhere - Can replace directly conventional air conditioning - Cooling-SPF much better than with chillers using air as heat sink

38. Some hints to reading from Europe:

39. Thank you very much for your attention!
Mit den folgenden Bildern können Sie die Zwischenfolien variieren – passend zur Veranstaltung.