Carbonated future

Published: Thursday 15 May 2008

Unable to cut down on its coal usage, it seems that the West is looking to burry its co2 emissions underground. The British government, for example, has become zealous about the carbon capture and storage (ccs) technology. Its high commission in Delhi has already organized two workshops on the technology this year.

The point of ccs is to continue making co2 but capture it, convert it into liquid by pressurizing, transport it over great distances, often across countries, and then inject it under pressure into the ground (see box A gas that will live underground). Aspects of the technology have been around for almost 60 years. For example, drinks are made fizzy by capturing carbon. But experts say that as an integrated technology, ccs is costly and fraught with risks.

The British government, however, holds up the technology as the key to energy security. At the first workshop in January, the uk's High Commissioner, Richard Stagg highlighted that ccs could reduce emissions while enabling the use of coal for development. "The uk has become the first country to support ccs on a commercial scale. We are keen to share our experiences with India," he said. At the second workshop in April, uk- based consultants Mott MacDonald released two studies on the financial aspects of ultra mega power plants (umpps) in the country, one of which recommends that new power stations in the country be equipped to use ccs at a later stage. At least nine umpps, each with a capacity of 4,000 mw are being planned for the country.

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Debbbie Stockwell, spokesperson of the uk's department of environment, food and rural affairs says that the Clean Development Mechanism (cdm) could mitigate the high capital costs of ccs. cdm is a tool under the Kyoto Protocol which allows developed countries to avoid the expense of cutting their emissions by paying developing countries for the technology to do the same--albeit less than what it would have paid at home. The inclusion of ccs as a project under cdm was discussed at the Bali climate change meet in December 2007 and is currently being negotiated.

Besides the British initiatives, studies have been conducted to gauge India's co2 storage potential. A map showing potential storage sites is being developed by the International Energy Agency's Greenhouse Gas Research and Development Programme and is expected to be released shortly-- Down To Earth has a preliminary draft of this map. Also in February, the Oil and Natural Gas Corporation signed an mou with the Norwegian company StatOilHydro to explore possibilities of ccs and cdm projects in the country.

The Indian government hasn't committed itself to ccs yet. The science and technology minister Kapil Sibal says, "We support the research and development activities, but would like that all concerns raised about the technology be addressed before adopting it."

The concerns that Sibal speaks of are quite a few. Anand Patwardhan, executive director of the Technology Information, Forecasting and Assessment Council, a ministry of science and technology body, raises two of them. "First is the issue of priority.Should we adopt ccs or invest in renewables and in efficient ways of burning coal?" he asks. Patwardhan also raises the issue of high costs of ccs. "The construction costs of a 500-mw power plant are likely to go up by us $300-400 if it has to be equipped with ccs facilities. Such a plant costs about half a billion dollars," he said (also see table costs of components of a ccs system).

Stockwell counters such criticism "No single technology will deliver the emissions reductions needed to avoid climate change. The uk government is committed to renewables, energy efficiency and carbon abatement technologies, such as ccs". But there are other question marks over ccs. Anil Razdan, the secretary at the power ministry, raised one of them at the January meet. "To separate and capture the co2 emitted by the power plant requires energy. This energy is derived from the power plant itself, thereby decreasing its efficiency. Estimates put this efficiency drop by about 10-15 per cent," he said.

Cost of components of a CCS system
CCS system components Cost range Remarks
Capture From a coal or gas fired power plant 15-75 US$/tCO2 net captured Net costs compared to the same plant without capture
Transportation Via pipeline or ship 1-8 US$/tCO2 transported Per 250 km pipeline or shipping for mass flow rates of 5-40 MtCO2/yr
Storage Geological storage 0.5-8 US$/tCO2 net injected Excluding revenues from enhanced oil recovery or enhanced coal bed methane
Geological storage monitoring and verification 0.1-0.3 US$/tCO2 injected This covers pre-injection, injection, and post-injection monitoring, and depends on the regulatory requirements

Ocean storage 5-30 US$/tCO2 net injected Including offshore transportation of 100-500 km, excluding monitoring and verification
tCO2 tonnes of carbon dioxide, Source Special Report on Carbon Dioxide

Costs and funds
In 2005, an Intergovernmental Panel on Climate Change (ipcc) report concluded that the costs of electricity produced from a ccs- equipped power plant would be us $0.01-0.05 more per kilowatt hour. This would mean an increase in the per unit cost of electricity by almost 50 per cent. Stockwell said that variation in energy markets makes it difficult to estimate electricity costs. "It is difficult to provide precise figures, given that the technology has not been demonstrated on a full-scale plant," she said.

As of now, no coal-fired power plant has been built with ccs technology. The FutureGen project in Mattoon, us, which by 2007 end, looked set to be the first plant to integrate all aspects of ccs, has run into trouble. Early this year, the us Department of Energy cancelled its funding for the project after the cost of the 275 mw plant doubled to us $1.8 billion (see 'Clean-coal too expensive' Down To Earth, February 29, 2008).

So far ccs has been confined to small projects. But Stockwell believes that the technology will receive an impetus once it's included under cdm. Patwardhan says this would be easier said than done. "I don't think we have any institution in the multilateral system that can spend that so much money on a single project. ccs is beyond the entire cdm market," he says. Anand Rao, assistant professor at the Indian Institute of Technology, Mumbai, who has researched ccs, raises another issue. "The storage site has to be monitored to ensure it is safe. This will escalate the already high costs of ccs."

Safety matters
The 2005 ipcc report pointed out that leakage from carbon leakage from geological formations could affect humans and contaminate groundwater. Rao says that, "Continuous leakage will partly negate the benefits of trapping co2 underground. It will also be a waste of the energy and money spent to inject co2 into the ground." He also says that "Storing co2 underground raises liability issues similar to that of nuclear waste."

The issues get even more complicated because co2 from one country will be stored in another or in international waters. There is no international regulatory framework pertaining to ccs yet.

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