june 2009 issue
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ENVIRONMENT COMMITTEE
Carbon Storage Momentum Builds
BY BILL CORBETT
Freelance Writer
In a world increasingly concerned about the growth of greenhouse gas emissions, Alberta has a problem. The province produces a lot of GHGs — more than 235 megatonnes of carbon dioxide equivalent per year, which is roughly a third of Canada’s total. Without concerted action, those emissions would reach 400 megatonnes by 2050 if oilsands projects, other industrial development and the population keep expanding.
In the short term, the province is focusing on reducing the intensity of emissions from large industrial sources. Alberta’s overall emissions are scheduled to fall to 14 per cent below 2005 levels by 2050. Although the targets have been criticized by some as too soft, they still represent a cut of some 200 megatonnes of emissions per year from projected levels by 2050.
Where will those big cuts come from? Energy conservation measures and clean, renewable technologies — among them bioenergy and wind, solar and geothermal power — are expected to account for 30 per cent.
The rest — 70 per cent of the reductions — are scheduled to come from projects involving carbon capture and storage, known as CCS. While carbon capture and storage projects lurch tentatively forward elsewhere in the world, Alberta is about to embark on an unprecedented CCS journey.
Big Dollars Coming
As early as this month, the provincial government will announce which of 11 short-listed projects will receive funding from a $2-billion program intended to kick start CCS. The federal government, too, is funding four Alberta CCS projects.
When all the funding announced by provinces and the federal government so far is included, the CCS total in Western Canada reaches $3 billion. Only the U.S. is spending more, at $3.4 billion.
The estimated three to five selected candidates in the Alberta program will then have six short years to put these plans into operation on a commercial scale, storing a total of five megatonnes of carbon dioxide per year by 2015.
One candidate is EPCOR’s proposed 270-megawatt Genesee Integrated Gasification Combined Cycle coal-fired plant, west of Edmonton, with carbon dioxide capture a key element of its design. “On the coal gasification side, there are four power plants in the world of a similar size to ours,” says David Lewin, P.Eng., EPCOR’s senior vice-president of the initiative. “None of the others, however, capture CO2. In many ways, this project would be the first of its kind in the world.”
Dr. Lewin says that having CO2 in the ground is possible by 2015, “provided everything lines up.”
The Genesee process would see carbon dioxide removed before combustion, after the conversion of oxygen, water and coal to synthesis gas. This development is complex, but generally speaking, carbon capture and storage are fairly straightforward, at least in theory.
Carbon dioxide is separated and captured, typically using chemical or physical absorption processes — and then compressed (at about 2,200 lb. per square inch) into a pipeline. At the far end of the pipeline, the CO2 is injected into long-term underground storage.
In Alberta, these storage sites include depleted oil and gas reservoirs, coalbed methane seams and saline aquifers several kilometres below the surface.
Carbon Capture’s History
Large, commercial-scale CCS projects are operating in Norway and Algeria, and smaller, pilot-sized ones are underway in other countries.
The North American energy industry has a long history of capturing CO2 and transporting it considerable distances for use in enhanced oil recovery projects, including EnCana’s Weyburn field in Saskatchewan. In Alberta, several pipelines carry captured CO2 relatively short distances to enhanced oil recovery projects.
“All the technologies we need to build this exist today,” says Kevin Heal, business development manager of carbon management in the Calgary office of Golder Associates. “But carbon capture and sequestration systems have not been built on this scale before.”
The good news is that most of the technical pieces are in place for CCS to work on a commercial scale in Alberta. First, the Western Canadian Sedimentary Basin, which produces so much petroleum wealth, also provides excellent geological structures for storing plenty of CO2.
Many of these storage sites are relatively close to large GHG emitters such as coal-fired power and petrochemical plants and oilsands upgraders.
As well, Alberta’s energy industry has expertise in engineering complex systems, building and operating pipelines, and injecting acid gas into reservoirs. This experience is complemented by a well-established regulatory regime through the Energy Resources Conservation Board, and considerable industrial and university research expertise, led by two decades of carbon storage investigations by the Alberta Research Council.
“Alberta has all the attributes necessary to build a carbon capture and storage industry,” says Mr. Heal. “We have huge and concentrated emissions, plus large potential storage locations, in a lot of cases close to emissions sources. We’ve got a world-class petroleum engineering community with a history of solving these types of problems.
“If this can’t work in Alberta, where on this planet is it going to work?”
Building the Skills
Still, specific skills must be developed to build and operate CCS projects, says Stefan Bachu, P.Eng., the research council’s principal scientist on CO2 geological storage. “Right now, there are no trained engineers, scientists, geoscientists and technicians to do the work,” he says. “We need to develop university courses and organize training. It’s something APEGGA should pick up the ball and run with.”
Other obstacles include tight deadlines and seamless integration of the three aspects of CCS — capture, transportation networks and storage — on an industrial scale. On the storage side, Dr. Bachu says, challenges include finding sites with the necessary capacity and injectivity rate for each large emitter, ensuring storage sites have little or no risk of leakage and resolving issues surrounding ownership of pore space.
But by far the biggest hurdle is cost.
“Carbon capture and storage is very expensive,” says Mr. Heal. “There are hundreds of millions of dollars (per project) of upfront investment in infrastructure and very significant operating costs. That’s why it’s important to do demonstration projects that prove the concept and provide experience for smart engineers, who can come up with ways of de-bottlenecking systems and reducing costs so the next generation of projects is less expensive.”
The current estimated cost of CCS is $80 a tonne or more. Considering the Alberta Government’s carbon price for large industrial emitters is $15 a tonne and European carbon market prices are hovering around $20 a tonne, there’s a large gap to fill to make this new technology economically viable. Establishing a carbon tax or cap-and-trade emissions system in North America would help close that gap and provide more regulatory certainty to industry. Ultimately, though, much of these costs will be passed on to consumers through higher energy prices.
Some 80 per cent of the CCS cost is in capturing and separating carbon dioxide from its emission source; the vast majority of Alberta’s emission sources have CO2 purities of less than 20 per cent. Thus while much of the public focus has been on capturing CO2 emissions from oilsands operations, knowledgeable observers feel it’s far better to concentrate initial efforts on Alberta’s coal-fired power plants.
These plants produce about half of the province’s CO2 emissions, are fewer in number, more concentrated in location and closer to potential storage sites. “It makes sense to go after the biggest, lowest-cost-per-tonne sources,” says David Keith, an international CCS expert. Dr. Keith is a director of the Energy and Environmental Systems Group of the Institute for Sustainable Energy, Environment and Economy at the University of Calgary.
Indeed, coal-fired power projects are well represented among the finalists for the Alberta Government’s $2-billion CCS funding program. EPCOR’s integrated facility would be Canada’s first commercial, near-zero emission coal gasification plant, with the potential to capture 1.2 megatonnes of CO2 per year. EPCOR is also proposing a 150-megawatt plant with post-combustion amine-scrubbing technology, removing up to 75 per cent of CO2 emissions, or nearly one megatonne per year.
Through a partnership with Enbridge Inc. and the Alberta Saline Aquifer Project, EPCOR would have the captured CO2 piped for use in enhanced oil recovery — perhaps in the Pembina oilfield — or for storage in deep saline aquifers.
Role in Oil Recovery
“The use of CO2 in enhanced oil recovery helps defray some of the cost of carbon capture and storage during the time that you’re working on the technology to reduce the costs of capturing,” says Allan Amey, P.Eng., lead author of a recent report by the Alberta Carbon Capture and Storage Development Council.
Meanwhile, TransAlta Corporation is working with Alstom Canada and TransCanada PipeLines to build one of the largest CCS facilities in the world — with an expected one megatonne of CO2 reductions — and the first to have an integrated underground storage system. Project Pioneer will use a chilled ammonia process for post-combustion CO2 capture and be applied to an existing TransAlta coal-fired plant west of Edmonton. Proponents say the technology could be applied, in Alberta and globally, to other coal-fired and industrial plants, including oilsands projects.
With current technologies, only a small portion of CO2 emitted by widely dispersed oilsands operations is readily captured. The industry’s brightest hope lies in adding carbon-capture facilities to new or retrofitted upgraders tied to the oilsands, clustered close to Edmonton and potential storage sites.
For example, Shell Canada’s Scotford Upgrader, on the government funding shortlist, is examining plans for a retrofitted system. The Quest CCS project could capture a megatonne of CO2 a year and perhaps inject some of it down a nearby storage well.
Beyond Carbon Capture
Despite the immense promise of carbon capture and storage, nearly all stakeholders agree it’s not the silver bullet for Alberta’s GHG emissions. On its own, it only gets rid of a carbon problem. What it doesn’t do is resolve the root causes. Such things as energy-efficiency initiatives, clean coal technologies and renewable energy projects are integral to the complete solution; their progress will be helped by higher carbon prices and a regulated trading system.
“CCS is only one option among many to reduce greenhouse gas emissions,” says Mr. Heal of Golder. “But if we’re going to be serious about reducing emissions on a scale that matters, it’s hard to envision solutions that don’t incorporate CCS.”
More Info
Alberta Energy CCS Site
www.energy.gov.ab.ca
Click on Key Initiatives
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