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Shallow Geothermal Energy for Heating and Cooling of larger buildings in commerce, offices, tourism

Dr. Burkhard Sanner VDI, Giessen, Germany

Content

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

Some statistics on ground-source heat pumps in Germany

Total number of installed, operational ground-source heat pumps

Calculated after data of BWP

0

50

100

150

200

250

300

350

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

nu

mb

er o

f G

SH

P u

nit

s o

per

atio

nal

(x

1000

)


Avoided CO2-emissions thanks to ground-source heat pumps

Calculated after data of BWP

0

100

200

300

400

500

600

700

800

900

1000

2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014

CO

2-em

issi

on

s re

du

ced

th

rou

gh

GS

HP

(K

t C

O2/

a)


Europe, installed capacity per country as of 2013

From EGEC Market Report 2013/14, update

4718

3282

1897

1517

999

923

764

513

338

334

287

246

218

173

173

154

103

64 58 56 39 21 21 11 6 6 2,1

2,0

3,1

26

769

0,3

0,3

0,2

0

500

1000

1500

2000

2500

3000

3500

4000

4500

5000

Sw

eden

Ger

man

y

Fra

nce

Sw

itzer

land

Fin

land

Aus

tria

Nor

way

Net

herla

nds

Ital

y

Pol

and

Den

mar

k

UK

Est

onia

Bel

gium

Cze

ch R

ep.

Irel

and

Spa

in

Gre

ece

Slo

veni

a

Lith

uani

a

Hun

gary

Tur

key

Slo

vaki

a

Rus

sia

Rom

ania

Ser

bia

Bel

arus

Bul

garia

Mac

edon

ia

Icel

and

Alb

ania

Por

tuga

l

Latv

ia

Bos

nia-

Her

z.

Ins

tall

ed

Ca

pa

cit

y (

MW

th)

shallow geothermal uses


Annual sales of ground-source heat pumps since 1978 and some events influencing this development

After data of BWP

0

5

10

15

20

25

30

35

nu

mb

er o

f G

SP

H s

old

an

nu

ally

in G

erm

an

y (

x 10

00

)

2nd oil price crisis

lack of knowledge and experience

1st RUS natural gas crisis

in 1985 start of dedicated R&D

1998 first draft of VDI 4640


Annual sales of ground-source and air-source heat pumps

10000

20000

30000

40000

50000

60000

70000

nu

mb

er o

f H

P u

nit

s so

ld

0

10

20

30

40

50

60

70

80

90

100

% G

SH

PAir

Geothermal

% GSHP

After data of BWP

German standards and guidelines for ground source heat pumps

DIN EN 15450 (2007-12):“Heating systems in buildings - Design of heat pump heating systems”(German adaptation of EN 15450)

EN 15450 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


DIN 8901 (2002-12):“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


VDI 4640 „Thermal Use of the Underground“:

• Part 1: General Issues / Licenses / Environment, revised 2010-04 (draft published 1998, original 2000-12)

• Part 2: Ground Source Heat Pumps, 2001-09 (original draft published 1998, draft of revised text 2015-05)

• Part 3: Underground Thermal Energy Storage (UTES), 2001-06 (revision ongoing)

• Part 4: Direct uses, 2004-09 (revision started)

• Part 5: Thermal Response Test, draft expected fall 2015

Covers all relevant aspects in very comprehensive wayStarted in 1995 following an initiative from the geothermal sectorElevated shallow geothermal from scratchbuilding to industrial product !


VDI 4640-2, draft 2015-05

• 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


VDI 4640-2, draft 2015-05Chapter 7 on borehole heat exchangers, systems <30 kW

Basic load profile for tables on specific heat extraction



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



Example of tables on specificheat extraction


VDI 4640-2, draft 2015-05Chapter 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


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“, 2012-08

• DVGW W120-2 „Qualification requirements for drilling technology and shallow geothermal energy (borehole heat exchangers)“, 2013-07

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

Heating and cooling with ground source heat pumps

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

www.rhc-platform.org


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)


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

Figure from Crandall (1946)electric m otor 3 hp (2,2 kW )

com pressor

warm air

expansion valve

pipes in the ground (garden)

blower 1/2 hp (0,36 kW )

Winter, heating


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

Figure from Crandall (1946)electric m otor 3 hp (2,2 kW )

com pressor

cold a ir

expansion valve

pipes in the ground (garden)

blower 1/2 hp (0,36 kW )

Summer, cooling


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 1990 (from Sanner , 1990)

Summer, coolingWinter, heating


Small optical factory with cooling of dust-free rooms (almost all year round) in Rathenow, 1992

Figure from Sanner (1993)


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 fromthe ground

Graph and photos VIKA / EWS


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)

Location: 65°51’ N


Heating and cooling with GSHP works far North:Hotel Storforsen in Bredsel, Älvsbyn, Sweden

Heatpum ps

(2 x 113 kW )prim ary circuit

Coolingm achines

re frigeratorsfreezers

33 Borehole heat exchangers each 160 m deep

H X H X

H X: H eat ExchangerE-boiler: E lectric heating (peak/back-up)TD : Tow el D ryingH W -St.: H ot W ater Storage

R echarge C ooling(room air)

secondary circ.

E -boiler

H X

Sw im m ing pool

F loorheating

H X

cold tap w ater

E-boiler

w arm tapw ater

TDH W -St.

DHW



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: Google

Photo: CRES



Further successful (non-residential) applications in Germany

- convention centre- factory- logistics facility- railway station- shopping mall - supermarket- town hall- …and many more

Leica Wetzlar – example of large, complex system

New headquarters of Leica AG, Wetzlar(inaugurated May 2014)

Photo: UBeG


New headquarters of Leica AG, Wetzlar

Located in a formermilitary area, now converted into a business- and science-park

Already other BHEsystems in same area



Total of 80 BHE each 120 m deep in two fields

Very complex energy system, including heat pump, CHP, peak boiler, absorption chiller, etc.

G as-Kessel

BH KWBH KW

Puffer-speicher

BH KW und Verte ilung H T-W ärm e

Absorpt.- Kältem . (KE1)

Verte iler Kälte (ZSp)

Luftkühler2 Not-Kälte-

m aschinen Luft

W T 3

Kühlung

H eizung

U nterverte iler in E rdw ärm esondenfe ld

ca. 130 kW zu w eiteren G ebäuden(nur Kälte)

Erdw ärm esonden-Verte iler kann so geschalte t werden,

dass H eizen/Kühlen auf beide Felder oder auf jeweils e ines

der Felder gefahren w ird.

Sprinklertank(a ls therm ischer Pufferspeicher)

W T 2a/b

direkte Kühlung

W T 1a/b

W T 5a/bW T4 W ärm e-

pum pe (W KE2)

Luftkühler (N ot/Spitze)

H eizen

aktiv Kühlen

im G ebäude

außerhalb G ebäude

U nterverte iler in E rdw ärm esondenfe ld

R K2

aktiv Kühlen

R K1

Nutzkälte

H eizung

Puffer-speicher W P und

Verte ilung N T-W ärm e

Notein-speisung

Not-Rück-kühlung BHKW

KE3/4

Kühlung M aschinen

W T 3a

Kühlung Beschichtung

W T 3b

Notein-speisung

Abwärm e D ruckluft

Simplified schematic of the energy system

FEFLOW- modeling to determine temperature distribution in the field and prove their is not interaction of the fields (figure: UBeG)



Photos: UBeG

Drilling with 3 rigs simultaneously (February 2012)

Finished BHE field before connecting (March 2012)

Bonner Bogen – new development on former industrial area

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

20042009


Groundwater heat pump system based on 6 wells

Photos and graphs: UBeG GbR / BonnVisio - Bonner Bogen


Groundwater heat pump system based on 6 wells


Final well diameter Ø 800 mm


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

neighbour

2004

2009

River Rhine



well 8The groundwater system provides ca 1 MW of heat and cold as baseload

Conclusions

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 20-50 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

Conclusions

Some hints to reading from Europe:

www.egec.org www.regeocities.eu www.rhc-platform.org

Thank you very much for your attention!

www.renewables-made-in-germany.com shallow geothermal energy for heating and cooling of larger...

Documents

ground source heat pumps

airsource heat pumps

heat pumps protection

germany annual sales

heat pipes special issues

direct expansion ground

data of bwp slide

germany german standards