Post on 30-Dec-2015
Life Cycle Greenhouse Gas Emissions from Electricity Generation
What is a life cycle for a person?
Birth & Childhood
Retirement & Death
Adulthood
What is a life cycle for a generating station?
Pre-operation
Operation & Fuel Cycle
Post-operation
Pre-operation
What activities release greenhouse gases before a generating station operates?
• Raw materials needed for construction are extracted
• Parts for the generating station are manufactured
• Parts for the generating station are transported to building sites
• Generating stations are constructed
Operation
What activities release greenhouse gases when a generating station operates?
• Electricity generated (may involve combustion of fuel)
• Maintenance (repair of the generator and replacement of parts)
• Maintenance of station building
Fuel Cycle
• Resource is located (exploration)
• Resource is extracted (e.g., mining operations)
• Processed resource is delivered to generating stations
• Resources is processed and/or refined
What activities release greenhouse gases related to the fuel some stations use?
Post-operation
What activities release greenhouse gases when a generating station closes?
• Dismantling (taking station apart)
• Decommissioning (take out of active service – shut down)
• Disposing and recycling
• Site reclamation (put back to the way it was)
Wind – when are GHGs emitted?
• Manufacture of parts
• Construction of wind turbines
• Transport to sites
• Installation
• No fuel required
• Maintenance and repair
• Taking apart• Transporting
parts off site• Recycling
parts• Reclaiming
land
500 MW = 250 wind turbines (2 MW/wind turbine)
Pre-operation
Operation & Fuel Cycle
Post-operation
Solar – when are GHGs emitted?
• Manufacture of parts
• Construction of solar panels
• Transport to sites
• Installation
• No fuel required
• Maintenance and repair
• Taking apart• Transporting
parts off site• Recycling
parts• Reclaiming
land
500 MW = 5 263 158 solar panels (95W/solar panel)
Pre-operation
Operation & Fuel Cycle
Post-operation
Coal – when are GHGs emitted?
• Manufacture of parts
• Transportation of parts
• Construction of station
• Extraction and processing of coal
• Transport to site• Combustion• Maintenance and
repair
• Taking apart• Transporting
parts off site• Recycling
parts• Reclaiming
land
500 MW = 1 large coal-fired generating station
Pre-operation
Operation & Fuel Cycle
Post-operation
Natural Gas – when are GHGs emitted?
• Manufacture of parts
• Transportation of parts
• Construction of station
• Extraction and processing of natural gas
• Transport to site (pipeline)
• Combustion• Maintenance
and repair
• Taking apart• Transporting
parts off site• Recycling
parts• Reclaiming
land
500 MW = 1 large natural gas-fired generating station
Pre-operation
Operation & Fuel Cycle
Post-operation
Nuclear – when are GHGs emitted?
• Manufacture of parts
• Transportation of parts
• Construction of station
• Extraction and processing of uranium
• Transport to site
• Maintenance and repair
• Taking apart• Transporting
parts off site• Recycling
parts• Reclaiming
land
500 MW = 0.77 nuclear reactors
Pre-operation
Operation & Fuel Cycle
Post-operation
Hydro – when are GHGs emitted?
• Manufacture of parts
• Transportation of parts
• Construction of station
• Flooding of land
• No fuel required
• Transport to site
• Maintenance and repair
• Taking apart• Transporting
parts off site• Recycling
parts• Reclaiming
land and water systems
500 MW = 1 large hydroelectric generating station
Pre-operation
Operation & Fuel Cycle
Post-operation
How do the methods compare?
Tonnes CO2e/GWh
Low Mean High
Coal 756 888 1 310
Natural Gas 362 499 891
Solar 13 85 731
Nuclear 2 29 130
Hydroelectric 2 26 237
Wind 6 26 124
Source: Comparison of Lifecycle Greenhouse Gas Emissions of Various Electricity Generation Sources, World Nuclear Association
CO2e = carbon dioxide equivalent of all GHGs emittedGWh = gigawatt hour = 109 Wh = measure of electricity generated over time