1. Presented by Sean Keegan
Suitable Build & Design
Lecturer Sonya Daly
GSHP Sustainable Build & Design Sean Keegan
2. GSHP uses Geothermal Energy from heat
exerted by the earths core
The ground maintains stable temperature
between 11-13oC
Energy can be recovered from the ground,
water or air but GSHP’s utilizes the stable
ground temperature as its source of energy
Substitute for conventional heating systems
Can be a considered zero-carbon source of
energy
GSHP Sustainable Build & Design Sean Keegan
3. Horizontal Collector system:
laid in trenches 0.5-1.8m
Vertical Collector system:
laid in bores 100-
150mm diameter &
20-150m deep
Direct expansion heat
transfer- open loop
Indirect expansion heat
transfer- closed loop
GSHP Sustainable Build & Design Sean Keegan
4. System consists of a ‘ground loop’ pipe
Filled with a mixture of water and antifreeze (Glycol)
buried in a trench or borehole
Electric pump powered by electricity/solar /wind
source circulates mixture in loop.
‘Pump up’ collected heat at low temperature and
release it at a higher temperature.
Transfers the heat collected to a hot water tank.
Heat is then used to supply under floor heating or
radiators.
Indirect system uses secondary pipe work and closed
loop.
Direct expansion heat transfer- open loop, more
efficient but environmental issues and more system
design needed because of inflexible copper work.
GSHP- Sean Keegan
5. Radiators, underfloor heating and hot water supply.
Recommended for newly constructed houses with
adequate insulation and air-tightness that meet the
latest building regulations.
Suited to homes with under-floor heating.
Not generally suitable for properties with existing
gas-fired central heating systems.
Temperature delivered between 45-55oC for
general use and 30-45oC for under floor heating.
Hot water in cylinder will be pumped up by an
emersion to meet require temperature.
Can be incorporated in concrete piles.
GSHP Sustainable Build & Design Sean Keegan
6. GSHP Sustainable Build & Design Sean Keegan
Materials
◦ Indirect Collector: highly-density
polyethylene pipe; flexible closed
loop
◦ Direct expansion: copper pipe; direct
installation
Methods
◦ Horizontal: trenches 0.5-1.8m deep,
excavated by a digger
◦ Vertical: bore holes 20-150m deep,
excavated by a drilling rig
7. Efficient performance needs good thermal contact
with the ground- so ensure adequate backfill
Supplys30-50% of hot water demands- topped up
electrical supply
Insulation costs vary depending on ground condition
and choice of vertical or horizontal vertical
€10,000-12,000
Payback 8-10 years, with a 20 year life expectancy
Every unit of electricity used by the pump, you get
between 3-4 units of heat
You still need to use electricity to drive the pump, so
a ground-source heat pump can’t be considered
completely zero-carbon unless this is provided by a
renewable source, such as solar power or a wind
turbine.
GSHP- Sean Keegan
8. GSHP Sustainable Build & Design Sean Keegan
15- 50% less than traditional electrical heating or oil
heating costs
No extra maintenance needed same as typical annual
boiler services
Low noise & good visual aesthetics; only pump visible but
usually in garage
cheaper off peak rates can be used to maintain heat within
cylinder
Can provide a well disturbed central heating system
Lower carbon emissions
Well suited for underfloor heating
9. Initial insulation costs are high
Groundworks required to dig the trench &
bore holes can be expensive and disruptive
Horizontal installation can be restricted by
the size of the building plot
Not suitable for properties with existing gas-
fired wet central heating as the technology
works at lower temperatures, making it better
suited to homes with under floor heating.
GSHP Sustainable Build & Design Sean Keegan
10. The Sustainable Energy
Authority Ireland operate a
Greener Homes Scheme that
provide grants to individuals
who wish to make there
homes more environmentally
friend
23% of applications are for
GSHP
The average successful
grant received is €2000
GSHP Sustainable Build & Design Sean Keegan
11. GSHP’s provide an environmentally friendly
heating source
Initial high investment with reduced utilities
bills
Suitable for new well insulated homes
GSHP Sustainable Build & Design Sean Keegan
12. Sustainable Energy Authority Ireland website
www.seai.ie
‘Ground Source Heat Pumps’ Home Heating
Systems www.which.co.uk
‘Assessment of Hybrid Geothermal Heat Pump
Systems ‘(2001), Federal Energy Management
Program, U.S. Department of Energy
‘Ground Source Heat Pumps: A Technology
Review’ (1999) by R. Rawling & J Sykulski,
Department of Electrical Engineering, University
of Southampton
GSHP Sustainable Build & Design Sean Keegan
