The need for geosequestration

Even with the strongest imaginable efforts to convert to alternative sources of energy, fossil fuels will continue to be the primary source of energy globally for decades to come.

The International Energy Agency (IEA) projects that global energy demand will increase by 45 per cent between now and 2030 – an average annual rate of increase of 1.6 per cent. More than 50 per cent of the increase in demand is forecast to come from China and India.

World energy demand expands by 45% between now and 2030 –an average rate of increase of 1.6% per year – with coal accounting for more than a third of the overall rise (World Energy Outlook - OECD/IEA 2008 ).

The IEA projects that 80 per cent of the energy demand in 2030 will be met from fossil fuels, fuels which when combusted for energy emit the greenhouse gas carbon dioxide. The largest increase in demand will be for coal, primarily to generate electricity in China and India. This is despite projected rapid increases in use of renewable energies, including wind, solar, and geothermal.

The IEA projects a 45 per cent increase in carbon dioxide emissions from energy between 2006 and 2030 given current policies, and warns that more than half of the projected electricity produced in 2030 could come from power stations that are already operating today.

Scenario analysis by the Intergovernmental Panel on Climate Change indicates that carbon dioxide emissions would have to peak before 2015 and then, by 2050, be reduced to 50 per cent to 80 per cent below year 2000 levels if the increase in global average temperatures from climate change is to be limited to 2 to 2.4°C.
Geosequestration – capturing carbon dioxide that would otherwise be emitted to the atmosphere and injecting it to be stored in deep geological formations – is the only technology available to make deep cuts in greenhouse gas emissions while still using fossil fuels and much of today’s energy infrastructure. The International Energy Agency describes it as “a promising technology for carbon abatement”. In its Special Report on Carbon Dioxide Capture and Storage, the Intergovernmental Panel on Climate Change said that geosequestration “has the potential to reduce overall (greenhouse gas) mitigation costs and increase flexibility in achieving greenhouse gas emission reductions. In its Climate Change 2007: Mitigation of Climate Change, the IPCC concluded that geosequestration was among the technologies with the largest economic potential to reduce emissions from electricity generation, as well as in the cement, ammonia, and iron manufacturing industries. It also found that attempts to stabilise greenhouse gas concentrations in the atmosphere at lower levels increased the emphasis on technologies such as geosequestration.

Geosequestration is not a replacement for taking actions which increase energy efficiency or maximise the use of renewable or other less-carbon-intensive forms of energy. A portfolio approach, taking every opportunity to reduce emissions, will be required to meet the challenge of minimising global climate change. Global modelling by CO2CRC indicates that widespread deployment of carbon dioxide capture and storage would result in atmospheric concentrations of carbon dioxide being at least 100 parts per million lower than would otherwise be the case.