In my first article for Energy Monitor, I describe the potential and economics of using the CarbFix procedure for capturing CO2 at point sources, dissolving it in water and injecting it into Icelandic’s porous basalt bedrock where the divalent metal cations of magnesium, iron and calcium in the bedrock react with the dissolved CO2 to form mineral carbonates and fill up pores in the bedrock. These minerals are stable for thousands of years.
In economic terms, the process is on a par with buying carbon credits: the net cost of capturing, dissolving and re-injecting CO2 in Hellisheidi using the CarbFix technology is about $US 25 [€21] per tonne, whereas emission credits cost around $29.5 (€25) per tonne – and are likely to increase in price as time goes on.
In collaboration with Swiss company Climeworks, CarbFix is also going to scale up its Direct Air Capture (DAC) prototype on Hellisheidi, from 40 tonnes per year to 4000 tonnes per year. This will make it the largest DAC project that will capture CO2 for geological storage. But it comes at a price – Climeworks say that their DAC projects in other countries cost $US 600-800 (€507-676). Undoubtedly the price will come down in due course, but at the moment it is unlikely to be important until later this century. Still, it has huge potential, as DAC plants can be set up anywhere.
Iceland will need to buy carbon credits next year for its heavy industry, according to the Environment Agency. But the heavy industries are also looking into the feasibility of using CarbFix for their emissions, so perhaps carbon credits will not be necessary.
Note that the Energy Monitor article was shortened considerably. For instance, this came out:
“Because geothermal plants such as Hellisheidi typically emit the irritant gas hydrogen sulphide (H2S) at the same time as CO2 and the CarbFix system allows other gases to be captured concurrently with CO2, both gases are captured and injected underground at the Hellisheidi plant.”
And here is more that came out:
Iceland (pop. 368,000) gets all of its electricity from renewable sources: geothermal, hydroelectric and wind. Of these, only geothermal power emits CO2, and its emissions are negligible when compared to electricity produced by fossil fuels. About 80% of Iceland’s electricity is used by heavy industry and last week the Environment Agency announced that Iceland would have to buy carbon credits next year, at the end of the Kyoto agreement.
The Environment Agency says that CO2 emissions from ferroalloys and aluminium smelters amounted to 1705.87 ktCO2 in 2019 while preliminary data from the Agency shows that total CO2 emissions for 2019 were 3618.13 ktCO2, excluding LULUCF, international aviation and navigation. Speaking unofficially, as the figures have not been announced publicly, Nicole Keller from the Agency says: “We have calculated that Iceland will need to buy approx. 4000 ktCO2 worth of credits. We do not have any figures for the cost associated with it, though. This is being looked at by a working group under the ministries.”
The CarbFix team say that they have been operating at an industrial level since 2014 and capture about 33.4 tonnes of CO2 a day or 12,000 tonnes annually.
The CarbFix website shows running totals of the CO2 injected, both on a daily basis and since the project was started on an industrial scale in 2014. By 16 November, over 71,750 tonnes had been injected during the last six years.
On a global scale, the total number of CCS facilities in various stages of development is now 59, with an annual capture capacity of more than 131 million tonnes. Of these, 21 facilities are currently in operation, 3 under construction, and 35 in various stages of development. Two of the large-scale facilities are connected to power plants, Petra Nova Carbon Capture in the USA (whose CCS operations have currently been suspended due to COVID) and Boundary Dam CCS in Canada (capacity 1 Mtpa), with the remainder 19 being in industrial applications. The CarbFix plant is not regarded as a large-scale facility because its capacity is small in global terms.
On a global scale, Iceland could theoretically accommodate over 400 GtCO2 in its active rift zone – far more than Iceland would ever be able to use. And for that matter, far more than the 107 GtCO2 that the International Energy Agency predicts will be in storage in 2060.