Comparing Electricity Technologies ‘98 US Electrical Consumption ‘98 US Electrical Consumption 3.6 million Gwh e 35% of US Primary Energy Consumption 35% of US Primary Energy Consumption 2,200 million Mg of CO 2 emissions 2,200 million Mg of CO 2 emissions ~5,500 million Mg of CO 2 total US emissions ~5,500 million Mg of CO 2 total US emissions

Electricity Mix 52% 14% 20% <0.05% Others:HydroOilGeothermalBiomass Coal Natural Gas Nuclear Solar Wind

Construction Manufacturing of plant components, including: Manufacturing of plant components, including: –mining materials (ie: iron) –processing materials (ie: steel) –construction of components (ie: solar cells) –energy for transportation Site construction includes energy for: Site construction includes energy for: –heavy machinery

Construction (tons of CO 2 per GWhe)

Fuel Production Exploration: Exploration: –energy required to find fossil fuel or uranium resources Mining, Processing & Refining Mining, Processing & Refining –energy and equipment requires to mine resources and convert it to usable fuel Transportation & Storage Transportation & Storage –energy required –possible leaks (ie: natural gas)

Fuel Production (tons of CO 2 per GWhe)

Fuel Consumption Burning fossil fuels is the biggest direct contributor Burning fossil fuels is the biggest direct contributor

Fuel Consumption (tons of CO 2 per GWhe)

Operation & Maintenance Electrical power is needed to keep plant running reliablyElectrical power is needed to keep plant running reliably Energy is needed to perform maintenance on the plantEnergy is needed to perform maintenance on the plant Equipment may need to be replacedEquipment may need to be replaced –this new equipment has all the same GHG emissions as the new equipment (ie. Construction)

Operation & Maintenance (tons of CO 2 per GWhe)

Decommissioning Energy required to dismantle power plant Energy required to dismantle power plant Energy required to destroy or dispose of used components Energy required to destroy or dispose of used components Energy required to reclaim land Energy required to reclaim land –heavy equipment for earth moving –reforestation –etc...

Decommissioning (tons of CO 2 per GWhe)

Total (tons of CO 2 per GWhe)

Assumptions Coal: Coal: –Based on 1000 MWe baseload coal station Gas: Gas: –Based on 450 MWe baseload equivalent gas station Nuclear: Nuclear: –Based on 1000 MWe baseload nuclear station Solar: Solar: –Based on 100 MWe facility located in the Southwest US –GHG emissions for decommissioning are based on known values for wind and estimated for solar through a comparison of solar and wind construction costs Wind: Wind: –Based on 25 MWe wind farm without storage –storage would increase emissions in construction and O&M (slightly in decomm.)