Methodology

1. LIFE CYCLE
ASSESSMENT
Water Heating Systems

2. Introduction
Life cycle assessment (LCA) phases

3. The study compares between three heating systems :
- Heat pump system
- Gas Boiler
- Electric Boiler

4. 1 Goals and Scope
1.1 LCA Objective
1.2 Expected Audience
2 System Boundaries
2.1 Conceptual Boundaries
2.2 Geographical Boundaries
2.3 Life Boundaries
3 Functional Unit

5. Fossil
Fuels
Materials
Transports
Metals Electronics Insulation Plastics Packaging Painting
Heat-pump
Construction
Electricity
and Heat
Electricity
Pump
Transports to
the Customer
Trans.
Ship
Heat-
pump
Heat-
pump
Pump
Disposal
Metals
50%
Electronics Insulation Packaging
LandfillRecycling
Refrigerant
Painting
Pump construction phase
Pump operation phase
Pump Transports phase
Pump Disposal phase
Coal
LCA system boundaries of the heat pump system

6. 4 Heating Load Determination Procedure
4.1 Hot Water Flow Rate ( 𝑚ℎ𝑜𝑡 = 𝑚 𝑚𝑖𝑥𝑒𝑑
T
mixed
–T
cold
Thot –Tcold
)
4.2 Steady State Heat Capacity
4.3 Energy Consumption
RF =
heating requirements
steady state heat output of boiler
Further,
RF =
burner run time
total monthly elapsed time
5 Economic Analysis

7. 6 Impact Assessment
6.1Life Cycle Phases
6.1.1 Construction
6.1.2 Transport
6.1.3 Operation
6.1.4 Disposal

8. 7 Results
7.1Energy Consumption Assessment
0
2000
4000
6000
8000
10000
12000
14000
16000
18000
1 2 3 4 5 6 7 8 9 10 11 12
Month
Monthly energy consumption kWh
Monthly energy
consumption/ Ele. Boiler
kWh
Monthly energy
consumption/ Heat Pump
kWh
Monthly energy
consumption/ Gas Boiler
kWh
0
500
1000
1500
2000
2500
3000
3500
4000
Consumption over 20 years MWh
Elec. Boiler
Heat pump
Gas Boiler

9. 7.2 Economic Assessment
0
50000
100000
150000
200000
250000
300000
Present worth
Present worth / electric boiler
$
Present worth / Heat Pump $
Present worth / Gas boiler $
Comparison between the electric boiler, the heat pump,
and the gas boiler present worth value for 20 years

10. 7.3 Environment Impact Assessment
0.000
0.000
0.000
0.001
0.010
0.100
1.000
10.000
100.000
1000.000
10000.000
100000.000
1000000.000
10000000.000
100000000.000
1000000000.000
10000000000.000
Construction Transportation Operation Disposal
Heat Pump Acidification potential - average Europe
Climate change - GWP100
Depletion of abiotic resources - elements, ultimate
reserves
Depletion of abiotic resources - fossil fuels
Eutrophication - generic
Freshwater aquatic ecotoxicity - FAETP inf
Human toxicity - HTP inf
Marine aquatic ecotoxicity - MAETP inf
Ozone layer depletion - ODP steady state
Photochemical oxidation - high Nox
Terrestrial ecotoxicity - TETP inf
Comparison between the impacts of each phase in heat pump life

11. 0.10
1.00
10.00
100.00
1000.00
10000.00
100000.00
1000000.00
10000000.00
100000000.00
1000000000.00
10000000000.00
100000000000.00
Heat pump Electric Boiler Gas Boiler
Impact Comparison for Operation Phase
Acidification potential - average Europe
Climate change - GWP100
Depletion of abiotic resources - elements, ultimate reserves
Depletion of abiotic resources - fossil fuels
Eutrophication - generic
Freshwater aquatic ecotoxicity - FAETP inf
Human toxicity - HTP inf
Marine aquatic ecotoxicity - MAETP inf
Ozone layer depletion - ODP steady state
Photochemical oxidation - high Nox
Terrestrial ecotoxicity - TETP inf
Comparison between the impacts of each system in operation phase

12. 0.10
1.00
10.00
100.00
1000.00
10000.00
100000.00
1000000.00
10000000.00
100000000.00
1000000000.00
10000000000.00
100000000000.00
Heat pump Electric Boiler Gas Boiler
Comparison Between The Impacts of All Phases
Acidification potential - average Europe
Climate change - GWP100
Depletion of abiotic resources - elements, ultimate
reserves
Depletion of abiotic resources - fossil fuels
Eutrophication - generic
Freshwater aquatic ecotoxicity - FAETP inf
Human toxicity - HTP inf
Marine aquatic ecotoxicity - MAETP inf
Ozone layer depletion - ODP steady state
Photochemical oxidation - high Nox
Terrestrial ecotoxicity - TETP inf
Comparison between the impacts of all phases together for three systems

13. 9 Sensitivity Analysis
9.1 Scenario I: Natural Gas
2 Scenario II: Neglecting Transmission and distribution Lines