Increasing greenhouse gas emissions may cause significant climate change. The most effective short-term strategies for reducing emissions from electricity production are substituting natural gas, nuclear, wind, or hydro power for coal. In the long term, increasing wind, nuclear, hydro, biomass, and solar power along with carbon sequestration techniques may become more cost effective compared to fossil fuels. Emerging technologies could also dramatically change energy production if developments like artificial photosynthesis or nuclear fusion become feasible.

1. Greenhouse Gas Mitigation:Greenhouse Gas Mitigation:
A Brief OverviewA Brief Overview

2. The ProblemThe Problem
 Increasing Greenhouse Gas (GHG) emissionsIncreasing Greenhouse Gas (GHG) emissions
may cause considerable global and regionalmay cause considerable global and regional
climate change.climate change.
 Global Warming Potentials (over 100 y):Global Warming Potentials (over 100 y):
 COCO22 11
 CHCH44 2323
 NN22OO 296296

3. World GHG Emissions by SectorWorld GHG Emissions by Sector§§
SectorSector COCO22 Emissions (GtC)Emissions (GtC) ShareShare growth rate†growth rate† rate trendrate trend
BuildingsBuildings 1.731.73 31%31% +1.8%+1.8% deceleratingdecelerating
TransportTransport 1.221.22 22%22% +2.5%+2.5% steadysteady
IndustryIndustry 2.342.34 43%43% +1.5%+1.5% deceleratingdecelerating
AgricultureAgriculture 0.220.22 4%‡4%‡ +3.1%+3.1% deceleratingdecelerating
Total EmissionsTotal Emissions 5.55.5 100%100% +1.8%+1.8% deceleratingdecelerating
(Total energy emissions accounted for 5.5 GtC emissions in 1995).(Total energy emissions accounted for 5.5 GtC emissions in 1995).

4. Mitigation of Greenhouse GasesMitigation of Greenhouse Gases
 Energy EfficiencyEnergy Efficiency
 Low or no carbon energy productionLow or no carbon energy production
 SequestrationSequestration

6. Best StrategiesBest Strategies
 The most cost effective short-term (2-20 y) strategies for avoiding emissions due toThe most cost effective short-term (2-20 y) strategies for avoiding emissions due to
electricity production are:electricity production are:
 Substitute natural gas for coalSubstitute natural gas for coal
 Substitute nuclear for coalSubstitute nuclear for coal
 Substitute wind for coalSubstitute wind for coal
 Substitute hydro for coalSubstitute hydro for coal
 For the longer term (20-100 y), the following methods of electricity productionFor the longer term (20-100 y), the following methods of electricity production maymay
become cost effective as fossil fuel costs increase:become cost effective as fossil fuel costs increase:
 More wind, nuclear, and hydroMore wind, nuclear, and hydro
 Biomass and energy croppingBiomass and energy cropping
 Coal fired electricity, hydrogen production with sequestrationCoal fired electricity, hydrogen production with sequestration
 SolarSolar
 Technology wildcards that probably aren’t likely, but could radically alter the mix:Technology wildcards that probably aren’t likely, but could radically alter the mix:
 Artificial photosynthesisArtificial photosynthesis
 Nuclear fusionNuclear fusion
 Other?Other?

7. Best StrategiesBest Strategies
 The most cost effective short-term (2-20 y) strategies for avoiding emissions due toThe most cost effective short-term (2-20 y) strategies for avoiding emissions due to
electricity production are:electricity production are:
 Substitute natural gas for coalSubstitute natural gas for coal
 Substitute nuclear for coalSubstitute nuclear for coal
 Substitute wind for coalSubstitute wind for coal
 Substitute hydro for coalSubstitute hydro for coal
 For the longer term (20-100 y), the following methods of electricity productionFor the longer term (20-100 y), the following methods of electricity production maymay
become cost effective as fossil fuel costs increase:become cost effective as fossil fuel costs increase:
 More wind, nuclear, and hydroMore wind, nuclear, and hydro
 Biomass and energy croppingBiomass and energy cropping
 Coal fired electricity, hydrogen production with sequestrationCoal fired electricity, hydrogen production with sequestration
 SolarSolar
 Technology wildcards that probably aren’t likely, but could radically alter the mix:Technology wildcards that probably aren’t likely, but could radically alter the mix:
 Artificial photosynthesisArtificial photosynthesis
 Nuclear fusionNuclear fusion
 Other?Other?