A new assessment report finalised by the Intergovernmental Panel on Climate Change (IPCC) concludes that capturing and storing the carbon dioxide (CO2) produced by power plants and factories before it enters the atmosphere could play a major role in minimising climate change.
Sources disclosed this here on Tuesday. They said that the "IPCC Special Report on Carbon Dioxide Capture and Storage" was written by 100 experts from over 30 countries and reviewed by many experts and governments. The report assesses the most up-to-date literature available in scientific and technical journals around the world and was requested by the parties to the United Nations Framework Convention on Climate Change (UNFCCC).
The report say that according to a number of studies, carbon dioxide capture and storage technologies (known as CCS) could lower the costs of mitigating climate change over the next 100 years by 30 percent or more. In addition, capture and storage of CO2 in geological formations could account for 15-55 percent of all emission reductions (equal to 220 to 2,200 billion tonnes of CO2) needed between now and 2100 for stabilising greenhouse gas concentrations in the atmosphere.
"Many components of carbon dioxide capture and storage technology were already mature, including several applications of CO2 capture, pipelines and gas injection into geological formations. Three CCS projects were already in operation in Algeria, Canada and the North Sea off the Norwegian coast. CO2 capture from large-scale power plants would require further demonstration over the coming years and decades. Other possible applications, such as ocean storage or fixing CO2 in stable carbonates, were still in a research phase," it added.
The report said that the potential of capture and storage could be limited by several important non-technology constraints. In particular, unless governments adopt climate-change policies that put a cost on emitting CO2, there would be no incentive to use these technologies. Furthermore, while the available storage capacity in geological reservoirs was "likely" to be sufficient, the true amount was yet uncertain. This was particularly so in some regions, which that were experiencing rapid economic growth, such as South and East Asia.
According to report, because CCS process requires energy, its adoption might increase the use of fossil fuels. For the same level of electricity production, a power plant with CO2 capture would require 10-40 percent more energy than a plant without capture. Under current conditions, adoption of CCS technologies would raise the cost, however the future costs of CCS could decline due to technological advances and economies of scale, perhaps by 20-30 percent over the next decade, assuming sustained R&D and deployment. On the other hand, rising oil prices could influence CCS costs. Such estimates for the current and future costs of CCS have significant uncertainties.
"The most economically feasible storage options for CO2 were geological formations, particularly given the experience already gained by the oil and gas industry. Fortunately, a large proportion of existing power plants and other "point sources" lie within 300 km of areas that potentially contain storage reservoirs, such as oil and gas fields, unminable coal beds and deep saline water-bearing formations," it observed.
It said, "Technologies for injecting captured CO2 into the oceans might also have potential, but they were still in the research phase and have not undergone full-scale testing. They involve releasing CO2 into the ocean water column via a fixed pipeline or a moving ship, or depositing it onto the deep seafloor at depths below 3,000 metres where CO2 was denser than water. However, there were concerns regarding the impact such technologies could have on ocean life and it was known that marine organisms could be harmed. Although the long-term environmental implications of changing the ocean chemistry in this way were unclear, the oceans could become significantly acidified if CO2 injection occurred on a large scale."
The report pointed out that technologies for storing CO2 virtually permanently by converting it into inorganic mineral carbonates were also in the research phase, and certain applications have been demonstrated on a small scale. "The energy requirements for this technology, however, were still unfavourable and would need to be further improved before it could become a real option. Using captured CO2 for chemical processes in industry was technically possible but has hardly any potential for net reduction of CO2 emissions," it added.