GEO-EXCHANGE
SYSTEMS
Presented by: Gordon McDonald,
P.Eng., C.Eng., LEED® AP
April 19th, 2011
Presented by
Gordon McDonald, P.Eng., C.Eng. LEED®AP
What is Geo-Exchange?
•  Terminology
  Earth source, ground source, ground coupling
  Not Geothermal which is a high grade energy source
•  Stored Solar Energy and
Conducted Heat from the
Earths Core
  Not a primary energy source
  Low grade heat source/sink
  Requires electricity and heat
pump to harvest useful
energy
•  Systems Consist of:
  Earth coupling
  Heat pumps
Presented by
Gordon McDonald, P.Eng., C.Eng. LEED®AP
Types of Ground Coupling (GHX)
Open Loop GHX
Presented by
Gordon McDonald, P.Eng., C.Eng. LEED®AP
Closed Loop
Horizontal GHX
Closed Loop
Vertical GHX
Heat Pumps
•  Moves heat from lower
temperature location (source) to a
higher temperature one (sink)


Vapour compression cycle
Electricity, compressor and refrigerant
•  Coefficient of Performance
  Measurement of efficiency
  Defines the ratio of useful energy to
the work input
•  Types of Heat Pumps
•
•
•
Water to water (CoP 5 – 6)
Air to water (CoP 3.5 – 4.5)
Air to Air (CoP 2.5 – 3.5)
Presented by
Gordon McDonald, P.Eng., C.Eng. LEED®AP
Kwantlen Polytechnic University –
Surrey Site
Presented by
Gordon McDonald, P.Eng., C.Eng. LEED®AP
Hesquiaht First Nation School
Presented by
Gordon McDonald, P.Eng., C.Eng. LEED®AP
West Vancouver Ocean Loop
•  Provide a DES using the sea as the low grade energy source
•  Islands used to stop coastal erosion allow installation of GHX loops
•  System consists of
•
•
•
180 exchange loops in the sea
Distributionn pipework on 22nd St
Energy transfer stations
•  Allows for sharing of energy at a community level
Presented by
Gordon McDonald, P.Eng., C.Eng. LEED®AP
Thank You
Closed Loop Horizontal GHX
Presented by
Gordon McDonald, P.Eng., C.Eng. LEED®AP
Closed Loop Vertical GHX
Presented by
Gordon McDonald, P.Eng., C.Eng. LEED®AP
Key Design Considerations
•  Site conditions
  Climate
  Topography
  Geology/ Hydrogeology
•  Building peak H&C loads
•  Building annual H&C energy
•  GXS System configuration
  Source side - GHX
  H&C plant – Heat pump technology
  Load side – HVAC system
Presented by
Gordon McDonald, P.Eng., C.Eng. LEED®AP
Key Design Considerations
•  Account for “thermodynamic response”
between GHX and building
•  Few “constant temperature” GHX
sources
•  Attention to long-term load variation
•  Environmental regulation
•  Groundwater protection
Presented by
Gordon McDonald, P.Eng., C.Eng. LEED®AP