At the coalface
Australia’s top scientific research organisation, the CSIRO, is actively working with several Chinese partners to confront the challenges of global warming accentuated by the rise of greenhouse gases.
Australian technology is at the forefront in tackling climate change in China. The challenge to reduce carbon emissions in China – or globally as CSIRO scientist Dr Paul Feron would say – cannot be underestimated, but it isn’t beyond reach provided there’s a willingness and a commitment to achieve goals.
Crucial to CSIRO thinking, in collaboration with its Chinese partners, is reducing carbon emissions from coal-fired power stations. In essence, this involves post combustion capture (PCC) of carbon dioxide (CO 2) at the source. The PCC process strips CO 2 from the flue gases at fossil-fuel driven industrial plants.
The PCC process involves several technologies at varying stages of development, which do work. But a key objective is to improve existing technologies and to develop new ones in a bid to sustain coal plant efficiency, while capturing carbon dioxide. Today, there’s an imbalance between capturing CO 2 and coal plant efficiency – an opportunity cost. Dr Feron explains that capturing 90 per cent of CO 2 doubles the cost of producing power and reduces a coal station’s efficiency from a maximum 40 per cent to an unsustainable 28 per cent.
“We are undertaking a lot of research on addressing the efficiency shortfall,” he says. Joining forces Research into PCC and improving efficiencies involve several stakeholders – notably the CSIRO, the Huaneng Group, one of China’s big five power companies, China’s Clean Energy Research Institute and the Chinese and Australian Governments.
The collaboration, which began in 2008, has evolved into a joint scientific team dedicated to finding practical solutions to China’s carbon footprint in a country that continues to post annual economic growth beyond eight per cent. Of course, China, often referred to as the engine room of the global economy, is a major carbon emitter as its industries work around the clock to churn out an increasing array of consumer products for world markets.
To keep up with industrial demand and to provide electricity to an estimated population of 1.3 billion people, Dr Feron says China is building a coal-fired power station every fortnight, so it will be emitting CO 2 for at least the next 40 years.
“With China growing at eight to nine per cent a year and its people striving to lift their living standards, there’s increasing demand for energy,” Dr Feron says. Coal accounts for about 70 per cent of China’s power needs, with the remainder made up of nuclear, gas, oil and, to a tiny extent, renewables – wind and solar.
According to Dr Feron, China accounts for about 10 per cent of the world’s CO 2 emissions. Yet, he says, cutting coal fired power in China by one per cent, in favour of alternatives, is the equivalent to powering a quarter of Australia’s electricity needs each year. China is generating more power from greener sources each year, says Dr Feron, but it’s coming off a very low base.
Work in progress
It’s against this backdrop that the CSIRO and its Chinese collaborators have embarked on several pilot projects, with the objective to reduce, or at least constrain CO 2 levels in China over the longer term. Dr Feron says ammonia and amine-based liquids that absorb CO 2 are another method of capture at the power plant. It’s essentially a separating process.
“In heating the liquid, the CO 2 bubbles out of the solution,” he says. “The CO 2 is captured, but the liquid can be reused in the absorption process. We are working with our Chinese partners on several liquid absorptive processes that won’t stifle plant efficiencies in line with carbon capture.” Capturing CO 2 also has the added benefit of cutting poisonous gases, such as sulphur dioxide, and the acid gas, nitrous oxide. After capture, CO 2 itself is compressed and cooled to form a liquid, and can be safely stored in porous rock up to four kilometres below the earth’s surface. Or, in certain locations, CO 2 can be used to extract more fossil fuels.
Dr Feron says CO 2 can recover additional oil that otherwise couldn’t be extracted from an oil field. He adds that injecting CO 2 displaces oil in the field, enabling it to be pumped to the surface. “It’s been a commercial practice in Texas for years and China is following,” Dr Feron says. “Carbon dioxide can also be injected into coal layers to extract methane.”
The Australian Government has committed between $10 and $12 million to a feasibility study that includes integrating full carbon capture at existing and new coal-fired power stations in China. The feasibility study will thoroughly examine the costs – planning permits, engineering, construction, storage and transportation – of capturing CO 2.
From little things...
Australia’s commitment to tackling climate change is well documented, with the introduction of a carbon tax from 1 July 2012. Today, coal generates about 75 per cent of Australia’s power needs, and is responsible for about 40 per cent of greenhouse gas emissions. The global warming debate has been robust, but Australia is committed to generating up to 20 per cent of its energy from renewable sources by 2020.
Significant investment already in wind, solar and geothermal energy is expected to grow exponentially. Australia’s Climate Institute estimates $31 billion of clean energy projects are already underway. Dr Feron says China, as a rapidly developing nation, is eager to draw on Australia’s bank of knowledge in dealing with global warming and carbon emissions.
“China is looking to Australia for assistance and is very interested in what we are doing,” he says. “After all, Australia and China have a good trading relationship.” He says China, despite its growing dependency on coal, is acutely aware of the impact that its industries are having on the global environment and its people.
“China is seriously considering an emissions trading system,” he says. “China wants to be a player in global warming solutions, and Australia’s scientific knowledge, backed by Federal Government investment programs, are geared towards helping China and Australia achieve its lower-emissions objectives.
“But China’s carbon emissions status has to be kept in perspective – you just don’t go from fossil fuels to emissions free energy in a matter of years. The switch to greener energies is an incremental process and one that has to be practical.”
Story by Anthony Black