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The Search for Clean Coal Technologies

by Ken Waldie Combustion-News Business Editor

A group of Canadian electricity generation utilities and a coal producer, in partnership with the government of Canada and three provinces, has set out to demonstrate the commercial viability of clean coal technologies. The Canadian Clean Power Coalition (CCPC) is made up of seven power companies that constitute roughly 90 percent of Canada’s coal-fired generation capacity. The Coalition was launched in June 2001 and has raised about $5 million in start-up funding contributed by its industrial members and both levels of government. The Electric Power Research Institute (EPRI) joined the Coalition in January 2002. The EPRI is engaged in a number of international clean coal research ventures, and its membership includes Canadian electricity utilities, including some that are not direct participants in the CCPC.

Kyoto Targets

Finding cleaner ways of burning coal is a major priority considering the ongoing debate about Canadian strategies for meeting Greenhouse Gas (GHG) reduction targets under the Kyoto Protocol. According to Environment Canada’s Third National Report on Climate Change, the combustion of fossil fuels for public electricity and heat generation accounted for 119 megatonnes of CO2 -equivalent emissions in 1999, about 17 percent of Canada’s total human-induced GHG emissions. Coal was the source of nearly 82 percent of electricity-related emissions, even though coal-fired generation accounts for only about 18 percent of the country’s power production. Today’s coal combustion practices convert only about one-third of the energy in coal to electricity. New technologies could lead to solutions that are both cleaner and more efficient. That’s one reason why Natural Resources Canada (NRCan) provides the Canadian Government contribution to the CCPC through two initiatives: the Industry Energy Research Development (IERD) Program, which is focused on energy efficiency, and Technology Early Action Measures (TEAM), which is concerned with climate change.

Coal combustion produces a number of harmful by-products, including sulphur dioxide, nitrogen oxides, and compounds of mercury, lead, and arsenic. But CO2 is the most serious challenge, because it cannot be removed using conventional “scrubbing” techniques. Moreover, carbon dioxide makes up 78 percent of Canada’s 1999 GHG emissions. The CCPC is in the early stages of a feasibility study that will guide the selection of technologies for two commercial-scale demonstration plants (roughly 300 megawatts each), one retrofitted (by 2007) and one Greenfield (by 2012). Bill Campbell, CCPC Project Manager, says that the flexibility to handle different types of coal found in various regions of Canada is a key consideration. “We’re looking at three representative coals,” he says, “Alberta sub-bituminous, Saskatchewan lignite, and coal used in Nova Scotia and Ontario, which is typically bituminous.”

Technological Options

Several technologies are likely to come into play in reducing GHGs and other emissions from coal-fired plants. While the CCPC is not ruling out other applications, the primary focus is on three technologies:

Campbell says that gasification is probably the best bet for a Greenfield plant, while the other two are better suited for retrofit to an existing plant. “With older plants,” he says, “getting value out of existing assets is critical to economic feasibility. If you built it 10 years ago, you want to scrap the least amount possible.”

There are a number of proprietary technologies for gasification and amine scrubbing, while the oxy-fuel approach is presently the least developed in commercial terms. The principle behind the oxy-fuel technology is that if coal burns in an environment where nitrogen is absent or minimized, the resulting CO2 will be vastly less diluted and therefore easier to sequester. While the underlying science has been developed by Natural Resources Canada, there has so far been no practical testing outside the laboratory. That’s one reason for the public/private-sector partnership that underlies the CCPC.

The oxy-fuel concept emerged at a theoretical level in the 1980s and has been the subject of important experiments in Canada, the US, and Japan. Canada became a leader in this effort when NRCan’s CANMET Energy Technology Centre launched the Vertical Combustor Research Facility (VCRF) in 1994. The Argonne National Laboratory in the US undertook similar experiments, as did Ishikawajima-Harima Heavy Industries (IHI), with funding from Japan’s Central Research Institute of Electric Power Industry (CRIEPI). Kelly Thambimuthu, NRCan’s leading expert on oxy-fuel and a member of the CCPCs Technical Committee, says that the technical feasibility of this technology has now been demonstrated, “but we now need to show commercial viability.”

To this end, the CCPC has commissioned engineering studies to estimate the baseline costs for existing technologies, including the pollution abatement retrofits that will be necessary regardless of any strategy chosen for CO2 sequestering. Once these base costs are established, it will be possible to estimate the marginal cost of removing CO2 . An important consideration, according to Thambimuthu, is that a new technology does not have to be 100 percent effective to be economically viable — it needs only to be at least as good as the next best alternative for substantial expansion of generation capacity: natural gas. Meeting that standard would require removal of roughly half of the CO2 contained in the emissions of coal-fired power plants, although a zero-emission solution remains the ultimate goal.

Funding Controversies

Public funding of clean coal technology development is not without controversy. Some environmental activists believe that coal should be phased out entirely and replaced by natural gas. Jack Gibbons, Chair of the Ontario Clean Air Alliance, states this position bluntly: “Coal is a 19th-century technology that has no place in 21st-century Canada. Clean coal is the coal industry’s equivalent of the tobacco industry’s safe cigarette.” Energy experts respond that while natural gas is becoming increasingly important, global energy demand is increasing much too quickly for gas (or other alternative energy sources) to provide all of the solution. Moreover, they say, Canada’s coal resources — some eight billion tonnes of proven reserves — are simply too valuable to waste. Jim Dinning, Executive Vice President for Sustainable Development and External Relations at TransAlta and Chair of the CCPC Management Committee, is a strong proponent of this position: “The coal resource in this country is massive,” he says, “and in most cases that asset belongs to the people. We pay a royalty on that resource. We don’t want to turn our backs on one of the world’s largest coal deposits and effectively throw it away. That would mean turning our backs on another natural resource advantage. We say don’t do that.”

Other critics of public funding say that if the electric power industry chooses to continue to use coal, it should pay for the technology itself to meet the air quality standards necessary for Canada to meet its Kyoto targets. Regardless of the source of funding, it is unlikely that clean coal technologies can be developed fast enough to meet the present targets, and this has fuelled further debate. The Canadian Electricity Association stated in a recent position paper that modeling results indicate that “in an economy-wide least-cost response to reaching the Kyoto target, based on domestic action alone, the electricity sector would be expected to contribute…between 40 and 60 percent of the total.” The paper goes on to say that reductions of this magnitude within the Kyoto time frame would have to come largely from the retirement of coal-fired plants, with reductions of up to 75 percent in coal-fired generation. The Association and other industry representatives say that as a result, substantial “stranded investment costs” would be passed on to consumers as existing plants were scrapped part way through their useful life.

Regional Dimensions

The uneven distribution of energy resources across Canada has further complicated this debate. Ontario, Quebec, British Columbia, Manitoba and Newfoundland all have substantial hydroelectric assets and are therefore less reliant on fossil fuels than the other provinces. Alberta, Saskatchewan, and Nova Scotia generate as much as 80 percent of their power from coal, and they have only limited hydro resources. These provinces also have substantial reserves of natural gas, but they are challenged to manage their endowments of non-renewable resources in a balanced way to achieve long-run sustainability. Any strategy that places a disproportionate burden on coal in meeting the Kyoto targets will therefore be seen as unfair and disruptive to Canada’s fragile regional balance. This makes the development of clean coal technology a national priority.

Ontario is also a major coal user, generating 24 percent of its electricity from five large coal-fired plants. But Ontario imports most of its coal from the United States and has no significant coal mining industry. The Ontario government is not presently participating in the CCPC, although government-owned Ontario Power Generation is a member.

Commercial Viability
Aside from the political debate, the CCPC faces significant technological obstacles in demonstrating the commercial feasibility of clean coal technologies. “It’s never been done before,” Campbell says. “We need new approaches, new ideas, and new attitudes. That means pushing manufacturers and pushing the engineering community to bring about a major change in the performance of technology. We want to start thinking about new and different approaches to reducing auxiliary power consumption, to reducing capital cost, to reducing operating cost, and to improving reliability.”

Commercial viability is especially important in light of the sweeping restructuring taking place in the electricity industry. Both Alberta and Ontario, which are home to about half of Canada’s population, have unbundled and deregulated their generation, transmission, and distribution systems and introduced “full retail access” that gives consumers a choice among private electricity providers. Several other provinces have introduced varying degrees of competition into their wholesale electricity markets, and large vertically integrated monopolies no longer dominate the industry. As a result, says TransAlta’s Dinning, the market will ultimately allocate the costs of clean coal technology. As was the case with tar sands development, he adds, government has a role to play in developing the basic technology. “But in the longer term, the application of that technology will have to be borne by the investors — the owners of the plants — and passed on to consumers.”

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