global CO₂ emissions

Energy-related CO₂ emissions are expected to increase globally at about 1.2 percent per year to 2030, reaching an annual level of 37 billion tonnes (top line of the chart) — even with aggressive assumptions for energy intensity improvements.

The selection of transportation and power generation “sensitivities” shown here illustrate the significant challenges — and the practical realities – the world faces in reducing emissions.

One of the options frequently discussed relates to the development of cellulosic ethanol. As a sensitivity, the growth of biofuels is doubled, enabled by a cellulosic ethanol breakthrough. The impact is hard to see on this chart, reducing CO₂ emissions by only about 0.5 percent in 2030.

Next, still in the transportation sector, doubling the expected rate of improvement in new vehicle fuel economy would reduce CO₂ emissions by about 1 percent in 2030. This relatively small impact reflects the time it takes for new vehicles to penetrate the market and begin to materially affect the results of the total fleet.

In the power generation sector, replacing one-half of the growth in coal for power with a “low carbon” alternative, either nuclear or IGCC with carbon capture and storage, would reduce CO₂ in 2030 by about 3 percent. To put this in perspective, replacing this coal capacity with all nuclear plants would require adding 125 more nuclear plants in addition to roughly 170 new plants already projected to be built in this timeframe. The effect of this change would be greatest in the non-OECD countries where coal use is growing for power generation.

As a last sensitivity, retiring all existing coal plants at 40 years was examined. Again, this would necessitate replacing these facilities with “low carbon” alternatives — nuclear or IGCC-CCS. This option would reduce CO₂ by about 10 percent in 2030. Again, for perspective, achieving this result by substituting nuclear plants in place of this coal capacity would require adding another 500 nuclear plants to the outlook by 2030. That is more than the number of nuclear plants that exist worldwide today.

Mitigation steps equivalent to all of these combined — even though each of these is highly unlikely — would be required to eliminate CO₂ growth within the next decade.