Now the second richest person in the world, Pretoria-born Elon Musk is at a loss to find worthy causes in which to channel his fortune. The Tesla and SpaceX CEO has so far managed to identify only one when last month he launched a competition with a $100m reward — the largest incentive prize in history — to anyone who can find a way to capture carbon directly from the atmosphere or oceans on a huge scale and lock it away safely.
The world’s leading scientists estimate as much as 6-gigatons of carbon dioxide (CO2) a year must be removed by 2030, and 10-gigatons a year by 2050 if we are to avoid the worst effects of climate change, Musk notes on the competition website. Never mind limiting carbon emissions, he is looking for innovation that will remove it from the atmosphere, ultimately saving all of humanity from the effects of climate change.
It is an ambitious goal. Especially if one considers how little traction carbon capture and storage technologies have had, despite being around since the 1980s.
In SA too it is slow going, despite a clear imperative to pursue such a solution in a coal-rich country stuck with a cash-strapped power utility.
Emitting just shy of 500-million tonnes of CO2 a year, SA is the 13th largest per capita air polluter on the planet and the largest generator of greenhouse gases on the continent, thanks to Eskom’s coal-fired power plants. As the tide against fossil fuels turns at increasing speed, a carbon capture and storage solution could be a saving grace for SA, but it is said to be at least a decade away from commercialisation.
As many Eskom power plants hobble towards the end of their life and decommissioning, it means that carbon capture and storage solutions will not be implemented in existing plants save for the Medupi and Kusile power stations, which will be decommissioned in 2069 and 2070, respectively, and any subsequent coal power plants — should they ever see the light of day.
As Eskom told parliament last week, it does not conduct its own research into carbon storage and transport options. Rather efforts in this field are co-ordinated through the SA Centre for Carbon Capture and Storage (SACCCS) which was established in 2009 in partnership with the department of energy, industry and international stakeholders and which sits within the Council for Geoscience.
Globally, the capture of carbon appears to be the easy part, though it can be costly.
According to IDTechEx Research, a market research firm, capturing CO2 directly from the atmosphere can be enormously expensive, costing about $600 a tonne. Capturing it directly from the source is substantially cheaper — one tonne of CO2 from a flue gas stream in an average coal-fired power plant now costs about $40-$80, says IDTechEx Research. Proponents of the technology, however, say it can today be done for as little as $20, making the economics compelling in jurisdictions where carbon taxes per tonne are high.
While the economics of capture appear to be improving, storage remains a challenge.
Once carbon is captured, it must then be transported to a suitable storage site — usually by pipeline — before it is injected into an appropriate geological storage site. That is porous rock formations, usually 1km-2km deep, which also have an impermeable rock cap to prevent the gas from surfacing. Over time, the Co2 solidifies into rock-like carbonate minerals underground.
An Atlas produced by SACCCS shows at least one mega tonne of geological storage is theoretically available in SA. That is more than four times what would be required to store half of SA’s annual emissions away for 100 years
Now a SACCCS pilot project, previously aimed for KwaZulu-Natal has refocused on Mpumalanga to be closer to the power plants and other facilities that are the major source of SA’s CO2. Potential storage sites have now been identified in Secunda and Volksrust.
Apart from storing captured CO2 underground it can also be used for various industrial applications including enhanced plant growth, waste water treatments and concrete curing.
Most industrial-scale facilities using captured CO2 use it for enhanced oil recovery where the gas is injected into oil wells to boost productivity. But, as IDTechEx Research notes, it requires high oil prices to be commercially viable.
“The drop in oil prices stemming from the Covid-19 pandemic made the enhanced oil recovery option less viable in 2020, resulting in the Petra Nova facility’s closure in Texas, which was the world’s largest installation of CO2 capture on a power plant,” it says.
Carbon capture and storage in SA appears light years away if one considers that it is struggling even to mitigate emissions of Sulphur dioxide, nitrogen oxides and particulates affecting air quality around the power plants. The Centre for Environmental Rights has launched a court case in a bid to compel the government to enforce its own air quality laws on polluters such as Eskom and Sasol.
As Eskom CEO André De Ruyter told parliament last week, it will cost R300bn to retrofit plants to comply with these standards and will add up to 10% on the tariffs. This estimate does not include any kind of carbon abatement, he said.
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