With growing international acceptance that negative emissions technologies will be necessary if the Paris Agreement global warming targets are to be met, attention is increasingly being focused on the range of cost effective technologies that might be used to remove carbon from, or prevent its release into, the atmosphere.
Carbon removal has in the past been regarded as an expensive secondary measure to reducing fossil fuel use in curbing greenhouse gases and, by some, a way to justify the continued use of fossil fuels. However, current analysis indicates that even if countries achieve their emissions reduction targets, it will still be necessary to actively remove carbon from the system to achieve the target of limiting global warming to less than 2 degrees Centigrade.
The Intergovernmental Panel on Climate Change (IPCC) estimates that the world will need to be removing an average of 10 gigatons of CO2 a year from the atmosphere by midcentury, and the economic potential of CCS could be between 10% and 55% of the total carbon mitigation effort until 2100.
Australia appears likely to be caught on the back foot in relation to the surge of investment interest in negative emissions infrastructure, although it was an early player in technology development through the Rudd government's $500 million National Low Emissions Coal Initiative.
Following the slashing of funding by the Abbott government for the Carbon Capture and Storage (CCS) component of this intiative in 2015 - by $460m to $191.7m - the Turnbull government announced the discontinuation of the Low Emissions Technology Demonstration Fund in the 2017 financial year, and the cessation of business case funding for the Carbon Capture and Storage Flagships program in the 2019 financial year.
In December last year, the Australian National Audit Office (ANAO) released a report into low emissions technologies for fossil fuels, finding that Australia's investments to date in two key programs – the the Carbon Capture and Storage (CCS) Flagships program and the National Low Emissions Coal Initiative (NLECI) - had lacked effective strategic governance, oversight and evaluation and had not yet seen any commercial application. Further the funding cuts for the programs had “not been supported by a strategic approach to applying remaining funding across the projects”, and the partner states and territories had not contributed the level of co-funding that had been envisaged.
The ANAO found that after the expenditure of $233 million on the National Low Emissions Coal Initiative (NLECI) and approximately $217 million on the CCS Flagships program, outcomes had been less than satisfactory.
“Funding under the NLECI program was originally directed towards five election commitments, three of which were unable to be fulfilled due to technical and/or financial reasons. The selection of replacement projects was not supported by a clear strategy, and therefore their alignment to the original election commitments is unclear.”
“The CCS Flagships projects are yet to reach the stage of deployable technology as originally envisaged in the program design. It is unclear whether the program is capable of delivering on its strategic policy objective as the program is due to close in 2020, and all program funding is currently committed.”
The future of negative emissions technologies
Possible approaches to carbon removal range from relatively low-tech but necessary approaches - such as broadscale reafforestation, conversion of agricultural waste to biochar for use in enriching agricultural soils, enhanced weathering which involves the use of silicate minerals (olivine) which react with CO2 in the air, and fertilising the ocean to increase phytoplankton growth - to the latest breakthroughs in carbon capture, utilisation and storage (CCUS) technologies.
Carbon Capture and Storage
CCS has to date primarily been the process of filtering CO2 from industrial flue gas and storing it permanently underground so that it doesn’t end up in the atmosphere. It involves expensive infrastructure, which has limited its uptake beyond the gas and oil industries, but some countries are planning full-scale CO2 capture facilities.
In 2016, the International Energy Agency noted that 15 large-scale CCS projects are already operating globally with a further seven expected to come online by 2018. The Sleipner project in Norway has been capturing CO2 from a natural gas production facility and injecting it in the Utsira sandstone formation beneath the seabed for the past twenty years, and has permanently stored more than 17 million tonnes (Mt) of CO2.
The Norwegian Government has set a goal to establish a complete carbon capture and storage (CCS) chain, including capture, transport and permanent storage, by 2022.
Touted as the world's largest carbon capture and storage project, Chevron's $2 billion facility attached to its Gorgon LNG project off northwest Australia, was due to start operating last year but has hit technical problems and will not start injecting CO2 any earlier than the December quarter of this year, and more likely early 2019, with the result that the Gorgon gas field will have been venting CO2 into the atmosphere for two years.
Meanwhile, the Petra Nova Carbon Capture project launched in the US in January last year to become the largest CCUS project in the world applied to a coal-fired power generation plant.
The EU's ERA-NET scheme has an ACT fund – short for “Accelerating CCS Technologies” - which has invested in a number of CCS technology development projects, including technological, logistics and infrastructure requirements to scale up CO2 capture, transport, use and storage.
In the UK, having spent £100 million on a competition to develop carbon capture technology for a £1bn contract before Treasury cancelled the project in 2015, the UK announced its Clean Growth energy strategy last October, including support for carbon capture, utilization and storage (CCUS), with up to £100 million to be invested.
A new CCUS Council has been appointed to work on deploying CCUS at scale in the UK and to work with industry group to identify the most appropriate way forward for development of CCUS industrial decarbonisation targets.
The UK will also develop a CCUS Cost Challenge Taskforce to deliver a plan to reduce the cost of deploying CCUS and will invest up to €111.5mil from the BEIS Energy Innovation Programme to support industry and CCUS innovation and deployment in the UK, including €22.3mil for CCUS demonstration programme to invest in new innovative technologies.
In south-western Victoria, the Cooperative Research Centre for Greenhouse Gas Technologies (CO2CRC) is managing the $100 million Otway research facility, claimed to be the world’s largest carbon capture and storage demonstration project with over 80,000 tonnes of CO2 injected and stored in a variety of geological formations.
Another emerging approach to CCS is Bioenergy with Carbon Capture and Storage (BECCS), which involves the use of biomass from crops or trees for industrial purposes such as pulp and paper manufacturing, ethanol plants and biogas plants or energy generation, and the geological burial of CO2 generated from those processes, resulting in negative net emissions.
The Global CCS Institute reports that 5-10 billion tonnes of CO2 from biomass could be removed from the atmosphere with BECCS annually in 2050.
Carbon Capture and Utilization
Carbon capture and utilization (CCU) involves the conversion of captured CO2 into useful products such as fuels and plastics, or use in processes such as enhanced oil recovery.
In India, a chemicals plant at the Tuticorin port has been converted to capture CO2 from its coal-fired boiler and convert it to sodium bicarbonate (baking soda). The commercial-scale plant, using technology developed by London-based Carbon Clean Solutions and built in partnership with Tuticorin Alkali Chemicals and Fertilisers, is capable of capturing 60,000 tons of CO2 annually at a cost of around $30 per ton. According to a report in Quartz, the next generation of the technology is likely to cut the cost to around $15 per ton, making it potentially commercially feasible for a wide range of applications.
The co-founder and CEO of Carbon Clean Solutions, Aniruddha Sharma, was recently awarded the title of New Asia Energy Leader 2017 at the second Asia-Pacific Forum on low-carbon technology.
In Zurich, Switzerland, a carbon capture plant was commissioned last year atop a waste incineration facility that sucks CO2 from the air using collectors developed by startup Climeworks that purify the CO2 so it can be sold for other uses or buried for storage. In this case, the collected CO2 is used to enhance the growth of tomatoes and cucumbers.