ENER-G Heat pump technology CPD

Ground Source Heat Pumps

Jason Cox – National Sales Manager

CPD

ENER-G Group Overview

CPD

Products & Solutions

ENER-G Sustainable Technologies

Heat pumps

Heat Pumps

Design Supply Install Commission Maintenance

Technology Principles

Standard Rating Conditions

GSHP – Brine 0C & Water @ 35/30C

ASHP – Air @ 7C & Water @ 35/30C

EN14511

ASHP Performance Curves

Heat Output kW

Entering Water Temperature 35°C

50 °C

ASHP Performance Curves

C.O.P.

Entering Water Temperature 35 °C

50 °C

Standard Rating Conditions

GSHP – Brine 0C & Water @ 35/30C

ASHP – Air @ 7C & Water @ 35/30C

EN14511

GSHP Performance Curves

Heat Output kW


50 °C

GSHP Performance Curves

C.O.P.


50 °C

Ground Source Applications

Collector Options

•Borehole Installation

•Slinky / Horizontal Installation

•Lake / Pond Loops

•Energy Pile Installations

Vertical & Horizontal Loops

Collectors & Chambers

Design Data

•Peak loads•Load profile•Geology•Available space

Ground Loop Design

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 = InputInput x Cost of energy = Annual running cost

*http://www.bre.co.uk/filelibrary/SAP/2009/SAP-2009_9-90.pdf

Ground Source Heat Pumps

System Capital Cost (£) Annual Running Cost (£) Carbon Output

GSHP 98,000 3,545(RHI £5,375)

16,211

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

Comparison Table (99kW)

System Efficiency (COP)

Capital Cost (£) Annual Running Cost (£)

Carbon Output

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(RHI £5,375)

16,211

*http://www.energysavingtrust.org.uk/Media/node_1422/Getting-warmer-a-field-trial-of-heat-pumps-PDF

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 solutionENER-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%.

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

Summary

Feasibility

Project Management

In-house drilling rigs & teams

In-house heat pump install team

Single point responsibility

Thank You

www.energ.co.uk

Gas Absorption Heat Pumps

Mark Wilson – National Product Manager

CPD

Contents

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

Absorption TechnologyDifferent types of GAHPBenefitsIntegration


Development of Gas Absorption Heat Pumps

Principle of Compression Heat PumpPrinciple of compression heat pump

USEFUL EFFECT

Principle of gas absorption heat pump

Expansion valve

Heat pump

Cold liquidVery cold liquid

Low temperature gas

Hot gas

Heating return

Expansion valve

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.

How does a GAHP work?

Expansion valve

Heat pump


Low temperature gas

Hot gas

Heating return

Expansion valve

1

2

3

4

5

6

7

1. Generator Within the generator, the low Nox gas-fired burner heats the ammonia/water solution via a heat exchanger, increasing the temperature and pressure. The strong ammonia vapour travels to the condenser (2) whilst the weak ammonia solution is circulated to the Absorber (5)


Expansion valve

Heat pump


Low temperature gas

Hot gas

Heating return

Expansion valve

1

2

3

4

5

6

7

2. Condenser The high temperature, high pressure ammonia vapour releases its heat into the heating system in the condenser. The vapour becomes a liquid and travels to the expansion valve (3) on its way to the evaporator (4)


Expansion valve

Heat pump


Low temperature gas

Hot gas

Heating return

Expansion valve

1

2

3

4

5

6

7

3. Expansion valve The high pressure ammonia passes through the expansion valve where the pressure falls. The ammonia now has a reduced boiling point and the liquid changes back to a vapour. This vapour passes on to the Evaporator (4)


Expansion valve

Heat pump


Low temperature gas

Hot gas

Heating return

Expansion valve

1

2

3

4

5

6

7

4. Evaporator A fan draws ambient air through the evaporator. The ambient air captured by the ammonia vapour, contains a high amount of free, renewable energy. The now heated, low pressure vapour passes on to the Absorber (5)


Expansion valve

Heat pump


Low temperature gas

Hot gas

Heating return

Expansion valve

1

2

3

4

5

6

7

5. Absorber In the absorber the weak ammonia solution recombines with the heated vapour, changing its state into a liquid. This releases further heat to the heating system. The now recombined ammonia solution is pumped (7) back to the generator.


Expansion valve

Heat pump


Low temperature gas

Hot gas

Heating return

Expansion valve

1

2

3

4

5

6

7

6. Second expansion valve This second valve controls the flow of weak ammonia between the Generator (1) and the Absorber (5)


Expansion valve

Heat pump


Low temperature gas

Hot gas

Heating return

Expansion valve

1

2

3

4

5

6

7

7. Heat pumpThe pump moves the ammonia solution from the Absorber (5) back to the Generator (1) where the process starts again.

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 consumption1/10 of an equivalent electrical heat pump.



• 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

GAHP GS: Ground source applications

Ground Source applications

Collector Options

•Borehole Installation

•Slinky / Horizontal Installation

•Lake / Pond Loops

•Energy Pile Installations

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 solutionENER-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

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

GAHP A: Air source

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

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



Direct use of energy CO₂ savings

http://www.carbontrust.com/media/18223/ctl153_conversion_factors.pdf

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*

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

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……..

Direct use of energy CO₂ savings

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

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)

Example : GAHP-A Air Source Heat Pump (36.2kW)(Running 60 hours per week / 6 months per year)

Annual running costs

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

Robur Gas Heat Pump (seasonal efficiency of

140%)= [1560(hrs) x 0.75(LF) x

36.2(kW) x 3.1(p/kWh)] / 1.40

= £ 938 per year

Condensing Boiler (seasonal efficiency of

90%)= [1560(hrs) x 0.75(LF) x

36.2(kW) x 3.1(p/kWh)] / 0.90

= £ 1,459 per year

Electric Air Source Heat Pump (seasonal

COP of 2.25)= [1560(hrs) x 0.75(LF) x

36.2(kW) x 11.46(p/kWh)] / 2.25

= £ 2,157 per year

Annual running costs

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

0

1020

30

40

5060

70

80

90100

110

120

130140

October November December January Febtuary March AprilMonth

Hea

ting

Load

[kW

]

GAHP

Boiler

Boiler

GSHP GAHP Covering Base LoadCovering Base Load



Integration of other heat sources

Thank You

www.energ.co.uk

ENER-G Heat pump technology CPD

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