Pacola and Socolow have shown that there are several established ways by which we can hold CO2 emissions at a constant level. Wind, solar, nuclear, carbon capture and storage, and fuel savings in transport are all methods that could make a significant difference soon. However, these all require a determination by governments and a realization […]

Finally, CO2 reduction can be obtained by enhancing natural sinks on land. Ending deforest­ation by 2055 and replanting some 250 million hectares of tropical forest, or a slightly larger area of plantations, would produce one wedge. When land is tilled for replanting, about half of the stored carbon in the soil is lost, mainly through […]

Introducing 700 GWe of nuclear power by 2055 would yield another wedge of C02 reduction. This is about double the total nuclear capacity deployed today. While the public is becoming less opposed to nuclear power, serious concerns remain about safety, waste disposal, and proliferation. The wind turbine generating capacity is currently about 40 GWp, which […]

Switching about 1400 GW of power from coal-fired to natural-gas-fired plants would also provide a wedge, since the amount of carbon from gas per kWh is about half that from coal. Of more long-term importance is the identification of a wedge from increased carbon capture and storage (CCS). One technique first produces hydrogen and carbon […]

In 2002 transport produced 22% of all CO2 emissions, with industry and buildings producing 36% and power generation 42%. A wedge would be provided by improving fuel efficiency from an expected 30 miles per gallon in 2055, from its present value of just over 20 to 60 miles per gallon, or by reducing the average […]

Stabilization at about 500 ppm requires holding the current emissions of 7 Gt C y"1 constant for the next 50 years, rather than letting them rise to around 14 Gt C y“!, which is roughly the rate expected if we allow the situation to follow the current trend. Assuming the same constant fraction of close […]

A renewables obligation is a mechanism set up in the UK to promote the growth of renewable energy. It requires electricity suppliers to obtain a specified fraction of their energy from generators using renewable energy sources. This fraction will increase to 10% by 2010. The obligation sets up a market in tradeable green certificates (renewable […]

A simpler scheme to set up than emissions trading is to impose a tax (collected by the government) on all fuels that emit CO2. The tax is based on the amount of carbon emitted, so coal would have a higher tax per kWh than gas. This scheme, which was introduced in Sweden, Finland, The Netherlands, […]