An introductory presentation on ENER-G ground source and gas absorption heta pumps

1. CPD
Ground Source Heat Pumps
Jason Cox – National Sales Manager

2. CPD
ENER-G Group Overview

3. Products & Solutions

4. ENER-G Sustainable Technologies
Heat pumps

5. Heat Pumps
 Design
 Supply
 Install
 Commission
 Maintenance

6. Technology Principles

7. Standard Rating Conditions
GSHP – Brine 0C & Water @ 35/30C
ASHP – Air @ 7C & Water @ 35/30C
EN14511

8. ASHP Performance Curves
Heat Output kW
Entering Water Temperature 35°C
50 °C

9. ASHP Performance Curves
C.O.P.
Entering Water Temperature 35 °C
50 °C

10. Standard Rating Conditions
GSHP – Brine 0C & Water @ 35/30C
ASHP – Air @ 7C & Water @ 35/30C
EN14511

11. GSHP Performance Curves
Heat Output kW
Entering Water Temperature 35 °C
50 °C

12. GSHP Performance Curves
C.O.P.
Entering Water Temperature 35 °C
50 °C

13. Ground Source Applications
Collector Options
•Borehole Installation
•Slinky / Horizontal
Installation
•Lake / Pond Loops
•Energy Pile Installations

14. Vertical & Horizontal Loops

15. Collectors & Chambers

16. Ground Loop Design
Design Data
•Peak loads
•Load profile
•Geology
•Available space

17. Assumptions
Output 99kW
Natural gas 3.1pkWh
Electricity 11.46p kWh
Running hours 1250
Electricity *0.524g/kWh
Natural gas *0.183g/kWh
Full load hours x Output (kW) = kWh divided by efficiency = Input
Input x Cost of energy = Annual running cost
*http://www.bre.co.uk/filelibrary/SAP/2009/SAP-2009_9-90.pdf

18. Ground Source Heat Pumps
System Capital Cost (£) Annual Running Cost (£) Carbon Output
GSHP 98,000 3,545 16,211
(RHI £5,375)
1250 kWh x 99kW = 123,750kWh per annum divided by 4 C.O.P = 30,938kWh
30,938kWh x 11.46ppkWh = £3,545 Annual Running Cost
RHI @ 4.3pkWh for installation less than 99kW

19. Comparison Table (99kW)
System Efficiency Capital Cost (£) Annual Running Cost Carbon Output
(COP) (£)
Boiler 0.9 15,000 4,262 25,162
ASHP *2.2 60,000 6,446 29,475
GSHP 4.0 98,000 3,545 16,211
(RHI £5,375)
*http://www.energysavingtrust.org.uk/Media/node_1422/Getting-
warmer-a-field-trial-of-heat-pumps-PDF

20. Longfield Academy case study
New-build high school combines ground source heat pumps and solar thermal technology for renewable heating and
cooling
The project
The construction of a new academy building for 1,150 students combines ground source heat
pumps, with solar thermal technology to maximise renewable energy efficiency.
The solution
ENER-G has installed 35 boreholes and completed work on the plant room, to accommodate four
ground source heat pumps with a combined capacity of 200kW. A total of 22 solar thermal panels
have been installed, covering 44 square metres of the Academy’s flat roof.
The benefits
•It is expected to achieve a minimum ‘Very Good’ rating under BREEAM for schools, as a result of
using renewable power sources, and extensive use of insulation to secure a thermal performance
15% beyond current standards.
•The installed renewable technologies will supply heating and hot water to the academy, together
with passive under-floor cooling in the summer months. This is projected to reduce the Academy’s
carbon dioxide emissions from its heating system by up to 40%.

22. Malvern Community Hospital case study
New hospital combines ground source heat pumps and a combined heat and power system to generate its own green
power.
The project
The new-build Malvern Community Hospital opened in autumn 2010 and provides both
in-patient and out-patient services. ENER-G delivered a solution that was considered the most
efficient means of meeting the building’s heating demands combining two low carbon
technologies – a ground source heat pump system and a combined heat and power (CHP) unit.
This is the first time that these technologies have been used in combination in the UK’s healthcare
sector.
The solution
The ground source system comprises 25 boreholes and two heat pumps with combined capacities
of 125kW for both heating and cooling. The ENER-G CHP system is a reciprocating gas engine
rated at 33kW of electrical output generating 55kW of useful thermal output for the building and
the ground loop for the heat pump.
The benefits
• The hospital has achieved BREEAM rating ‘Excellent’ and is projected to save on its energy bills
and reduce its carbon emissions by 15 tonnes per annum.
• A low maintenance option, with the ground source system having a lifetime in excess of 50
years, and the heat pumps lasting up to 25 years.
• With the presence of a CHP system at the same site the electricity generated by the CHP unit
can be utilised to power the heat pump

24. Summary
 Feasibility
 Project Management
 In-house drilling rigs & teams
 In-house heat pump install team
 Single point responsibility

25. Thank You
www.energ.co.uk

26. CPD
Gas Absorption Heat Pumps
Mark Wilson – National Product Manager

27. Contents
Gas Absorption Heat Pumps
- Absorption Technology
- Different types of GAHP
- Benefits
- Integration

28. Gas Absorption Heat Pumps
Absorption Technology
Different types of GAHP
Benefits
Integration

29. Development of Gas
Absorption Heat Pumps

30. Principle of compression
Principle of Compression Heat Pump
heat pump

31. Principle of gas absorption
heat pump
Expansion valve
Low temperature
gas
Hot gas
Heat pump
USEFUL
EFFECT
Heating return
Very cold Cold liquid
liquid Expansion valve

32. How does a GAHP work?
1. Gas burner heats ammonia and water
solution.
2. Ammonia gas enters condenser,
condenses and releases heat.
3. High pressure ammonia liquid converted
into low pressure ammonia liquid.
4. Ammonia liquid evaporates and draws in
heat.
5. Ammonia gas absorbs into ammonia
water solution.
6. Solution pump powers process.

33. How does a GAHP work?
1. Generator
Within the generator, the
low Nox gas-fired burner
heats the ammonia/water Expansion valve
solution via a heat
exchanger, increasing the 6
temperature and pressure.
1
The strong ammonia
vapour travels to the
condenser (2) whilst the Low temperature 5
weak ammonia solution is
circulated to the Absorber
gas 7
(5) Hot gas
Heat pump
4 2
Heating return
Very cold Cold liquid
liquid Expansion valve
3

34. How does a GAHP work?
2. Condenser
The high temperature,
high pressure ammonia
vapour releases its heat Expansion valve
into the heating system
in the condenser. The 6
vapour becomes a liquid
1
and travels to the
expansion valve (3) on
its way to the Low temperature 5
evaporator (4)
gas 7
Heat pump Hot gas
4 2
Heating return
Very cold Cold liquid
liquid Expansion valve
3

35. How does a GAHP work?
3. Expansion valve
The high pressure
ammonia passes
through the expansion
valve where the Expansion valve
pressure falls. The 6
ammonia now has a
reduced boiling point 1
and the liquid changes
back to a vapour. This
vapour passes on to Low temperature 5
the Evaporator (4) gas 7
Heat pump Hot gas
4 2
Heating return
Very cold Cold liquid
liquid Expansion valve
3

36. How does a GAHP work?
4. Evaporator
A fan draws ambient air
through the evaporator.
The ambient air captured Expansion valve
by the ammonia vapour,
contains a high amount of 6
free, renewable energy.
1
The now heated, low
pressure vapour passes on
to the Absorber (5) Low temperature 5
gas 7
Heat pump Hot gas
4 2
Heating return
Very cold Cold liquid
liquid Expansion valve
3

37. How does a GAHP work?
5. Absorber
In the absorber the weak
ammonia solution
recombines with the heated Expansion valve
vapour, changing its state
6
into a liquid. This releases
further heat to the heating 1
system. The now
recombined ammonia
solution is pumped (7) back Low temperature 5
to the generator. gas 7
Heat pump Hot gas
4 2
Heating return
Very cold Cold liquid
liquid Expansion valve
3

38. How does a GAHP work?
6. Second expansion valve
This second valve controls the
flow of weak ammonia
between the Generator (1) and
Expansion valve
the Absorber (5) 6
1
Low temperature 5
gas 7
Heat pump Hot gas
4 2
Heating return
Very cold Cold liquid
liquid Expansion valve
3

39. How does a GAHP work?
7. Heat pump
The pump moves the ammonia Expansion valve
solution from the Absorber (5)
back to the Generator (1) where 6
the process starts again.
1
Low temperature 5
gas 7
Heat pump Hot gas
4 2
Heating return
Very cold Cold liquid
liquid Expansion valve
3

40. The Technology
• Water-ammonia sealed circuit : no
top-up, no drain, extremely simple
maintenance;
• Natural refrigerant : no CFC, HCFC,
HFC;
• One single moving component
(solution pump) : very high reliability;
• Exhaust flue gas water vapour
condensation: reduced energy losses
in the exhaust gas;
• Very low electrical consumption
1/10 of an equivalent electrical heat
pump.

41. Gas Absorption Heat Pumps
Absorption Technology
Different types of GAHP
Benefits
Integration

42. GAHP GS: Ground source
applications
• Nominal efficiency 170% by means of heat recovery from renewable source (ground)
• LT or HT versions (55 °C / 65 °C)
• Domestic Hot Water production up to 70°C
• Indoor installation
• Reduction in borehole quantity by up to 60%
• Cheaper civils costs against electric ground source

43. Ground Source applications
Collector Options
•Borehole Installation
•Slinky / Horizontal
Installation
•Lake / Pond Loops
•Energy Pile Installations

44. The Open University
The UK’s largest closed-loop ground source, gas absorption heat pump project,
providing low carbon heat and reducing energy consumption by up to 50%
The project
Building 12 is a 2,000m2 new-build development that forms part of the Walton Hall
Campus. The new building is targeting a BREEAM ‘Outstanding’ rating. It incorporates
natural ventilation, night time cooling, solar chimneys, automatic lighting controls, a green
roof, solar water heating and photovoltaic panels.
The solution
ENER-G drilled 13 boreholes to a depth of more than 100 metres to install a ground loop
system that feeds four gas absorption heat pumps, with a combined capacity of 140kW heat
output. This system supplies the building’s heating requirements and will achieve carbon
dioxide savings of approximately 45%, in comparison to a system heater via a condensing
boiler
The benefits
•Energy consumption reductions of up to 50%
•Exemption from the climate change levy
•Cost savings relating to the Carbon Reduction Commitment (CRC) energy efficiency scheme
and improved Building Energy Certificate ratings (EPC and DEC)
•Reduced regulatory costs as a result of low emissions, enabling points for BREEAM
assessment and compliance with Part L2A and Part L2B of the building regulations

45. GAHP A: Air source
applications
•Nominal efficiency 165% by means of heat recovery from renewable source (air)
• LT or HT versions (55 °C / 65 °C)
• Domestic Hot Water production up to 70°C
• Outdoor installation to free up plant room space
• Minimal drop off of output and efficiency in low ambient temperatures against electric heat pumps

46. GAHP A: Air source

47. GAHP AR: Alternate heating
and cooling
• Heating or cooling from the same unit
• 2-1 ratio of heating to cooling
• Efficiency in excess of 144%
• Outdoor installation to free up plant room
space

48. GAHP ACF & WS: Simultaneous
production of hot/cold water
• Heating to cooling ratio 2.5 to 1
• Efficiency in excess of 227%
• Indoor installation
• Very low electrical consumption

49. Gas Absorption Heat Pumps
Absorption Technology
Different types of GAHP
Benefits
Integration

50. Direct use of energy CO₂
savings
h
t
t
p
:
/
/
w
w
w

51. Direct use of energy CO₂
savings
• Gas produces 0.1836 kgCO₂ / kWh
• Electricity from the grid produces 0.5246 kgCO₂ /kWh
http://www.carbontrust.com/media/18223/ctl153_conversion_factors.pdf*

52. Direct use of energy CO₂
savings
• Utilized electricity from the grid produces 3* times the CO₂ of
natural gas
• Electric HP Seasonal COP 2.25**
• GAHP Seasonal GUE 1.4
Therefore a gas absorption heat pump produces 46 % less
CO₂/kWh than a air source heat pump.
• If we use an example of 60 hours per week 6 months of the
year…..
http://www.carbontrust.com/media/18223/ctl153_conversion_factors.pdf*
**http://www.energysavingtrust.org.uk/Media/node_1422/Getting-warmer-a-field-trial-of-heat-pumps-PDF

53. Direct use of energy CO₂
savings
Example: GAHP-A Air Source Heat Pump (36.2kW)
(Running 60 hours per week / 6 months per year)
Robur Gas Heat Pump
= 1560 (hrs) x 25.7 (kW gas) x 0.1836 (kgCO2/kWh gas)
= 7.3 Tonnes of CO2 per year
Electric Air Source Heat Pump (seasonal COP of 2.25)
= 1560 (hrs) x 16 (kW electricity) x 0.5246 (kgCO2/kWh elec)
= 13 Tonnes of CO2 per year
To put that into perspective……..

54. 1 year’s CO₂ difference would fill the Olympic swimming pool at the
2012 games 12 times!

55. Also take into account…
No use/leakage of F-Gases
A typical 37kW air to air electric heat pump contains about 14kg of R410a gas.
If the leakage from the system is for example 10% of the charge per year
*(estimates put the Global Annual leakage rates of refrigerants at 27.8% !!)
This is equivalent to 2.5 Tonnes of CO2 per year
Another 5 swimming pools worth!
* Institute of refrigeration report 2008 (New high pressure Low GWP refrigerant blends)

56. Annual running costs
Example : GAHP-A Air Source Heat Pump (36.2kW)
(Running 60 hours per week / 6 months per year)
Robur Gas Heat Pump Condensing Boiler Electric Air Source
(seasonal efficiency of (seasonal efficiency of Heat Pump (seasonal
140%) 90%) COP of 2.25)
= [1560(hrs) x 0.75(LF) x = [1560(hrs) x 0.75(LF) x = [1560(hrs) x 0.75(LF) x
36.2(kW) x 3.1(p/kWh)] / 36.2(kW) x 3.1(p/kWh)] / 36.2(kW) x 11.46(p/kWh)] /
1.40 0.90 2.25
= £ 938 per year = £ 1,459 per year = £ 2,157 per year
Saving £500 over a condensing boiler or £1200 over an Electric Heat
Pump
Note: gas and electricity prices from SAP 2009
http://www.bre.co.uk/filelibrary/SAP/2009/SAP-2009_9-90.pdf

57. Annual running costs
There are significant running cost
savings to be achieved by using a
Gas Absorption Heat Pump.

58. GSHP GAHP Covering Base Load
Covering Base Load
140
130
120
Heating Load [kW]
110
100
90
Boiler
80
70
60
50
Boiler
40
30
20 GAHP
10
0
October November December January Febtuary March April
Month

59. Gas Absorption Heat Pumps
Absorption Technology
Different types of GAHP
Benefits
Integration

60. Integration of other heat
sources

61. Thank You
www.energ.co.uk