The Canadian province of Saskatchewan is faced with a dilemma. It possesses large reserves of coal relatively near population and industrial centres. This coal currently fuels power stations providing nearly 50 per cent of the province’s electrical power. There is a commitment to power production from cleaner fuel sources and from renewable energy but, for the short and medium terms, coal will remain an important fuel for power production. In 2011, the Canadian Federal Government announced strict performance standards for new coal-fired power stations. These regulations are expected to result in a reduction of greenhouse gas (GHG) emissions in Canada of about 214 mega-tonnes, the equivalent of taking 2.6 million personal vehicles off the road each year. Canada is committed to meeting its international obligations to reduce GHG emissions and unless Saskatchewan can find a cleaner way to burn coal, these power stations will be taken out of operation.
The argument for the continued use of coal for Saskatchewan’s power generation is compelling. Wind and solar can only provide power part of the time. In Saskatchewan, wind turbines can produce power to meet its needs 40 per cent of the time. Solar power generation could meet power needs up to 15 per cent of the time but the climate and geography of Saskatchewan make it expensive. Hydroelectric power is another option. It has low operating costs but comes with high construction costs. The province’s flat landscape and lack of major rivers limits the opportunities for this method of power production. Economically replacing coal would be a challenge.
Carbon capture and storage (CCS) is the process of trapping the carbon dioxide produced by burning fossil fuels and storing it in such a way that it is unable to enter the atmosphere. CCS technology is widely assessed as critical to securing the long-term sustainability of coalfired power production in Saskatchewan and around the world. The first carbon storage project date back nearly four decades and projects have successfully stored CO2 underground for more than 30 years.
Recently, the Boundary Dam Power Station near Estevan in south-eastern Saskatchewan became the first commercial scale power station in the world to successfully use CCS technology. Boundary Dam is not the first, nor will it be the last, coal-fired power station that will use CCS technology but its size is unique. The capture of GHG occurs in a two-stage process after the coal has been burned. Captured sulphur dioxide is converted to sulphuric acid and sold as a by-product. Storage of the CO2 takes place 3.4 kilometres deep in a formation layer of brine-filled sandstone.
The statistics of the Boundary Dam CCS power production unit are impressive:
- It produces 115 megawatts of power, or enough to power about 100,000 Saskatchewan homes.
- It can capture as much as 1.3 million tonnes of CO2, the equivalent of taking more than 300,000 cars off the roads.
- It can capture 90 per cent of the CO2 produced by the coal burning process.
- It is also capable of reducing sulphur dioxide (another GHG) emissions by 100 per cent.
- In July 2016, it was announced that the Boundary Dam CO2 capture unit has surpassed the capture of one million tonnes of CO2 since operations began in October 2014.
Boundary Dam, however, is no magic bullet that will provide the solution to GHG emission reduction overnight. It has experienced technical difficulties and shutdowns. The statistics above have been questioned, particularly by environmental groups critical of the continued use of coal as a fuel source. The capturing of GHG requires energy which reduces a plant’s ability to make electricity, the whole point of its existence. There are still basic questions of whether CO2 can be safely stored underground and under what conditions. Most importantly, the technology is expensive. The upgrading of the Boundary Dam plant alone cost $1.2 billion, two-thirds of which went for the equipment to capture the GHG. The Boundary Dam project and CCS in general, is a work in progress. It has, however, demonstrated the concept on a scale that is exciting but research continues and the Saskatchewan power industry has articulated its commitment to improving processes and cost efficiency.
Australia, like Canada, possesses significant coal reserves close to major population centres, particularly on the east coast. The Australian Federal Government has a stated commitment to meeting international GHG emission reduction targets but, to date, how this is to be achieved is unclear. The contribution of the coal industry to regional employment and the national economy is significant but industry research and development into CCS has not matched efforts overseas. The Federal Department of Industry Innovation and Science, through the CCS Flagship programme, promotes the wider dissemination of CCS technologies by supporting a small number of demonstration projects that capture CO2 emissions from a range of industrial processes, provide transport infrastructure (generally pipelines) and safely store CO2 underground in stable geological formations. This contribution is significant but small.
The problem of atmospheric GHG is immense and no single reduction strategy is likely to suit all situations and circumstances. CCS for coalfired power stations is controversial but its development and use should be based on sound scientific, economic, environmental and social research and reasoning. It is in Australia’s interest to contribute to that debate.