Mijndert van der Spek opened this keynote by emphasising the reality of DACs.Companies like Climeworks ORCA and Carbon Engineering are gearing up the technology, the latter for use in CO2 enhanced oil recovery. Although the principle of the system is straight forward there are 10 variations mostly in the capture system.These vary considerably in terms of technological advancement, energy use, energy costs and the levelized cost of net CO2 removal. The Heriot-Watt research team have independently projected the cost of 4 DAC technologies: alkaline solvent with lime looping; alkaline solvent with electrochemical regeneration; solid sorbent; and magnesia looping/ambient weathering. Unsurprisingly this technological analysis shows that there are large ranges and uncertainties with these parameters. First-of-a-kind costs are high for modular technologies but when compared to the development of wind power there is a discernible downward trend towards comparable cost levels.


Mijndert van der Spek proposed policies to help shift the technology to a more economically viable CDR. The enablement of a market accompanied by accelerated scale-up with parallel hands-on learning. This research team quantitatively assessed 4 options based on these policies. Their overall assessment concluded that DAC requires a whole CCS system but it was capable of delivering net negative emissions and more successfully that renewables. There are many emerging DAC technologies but the current information basis is very weak. Although costs are high now there is confidence that cost reduction to 100's US$/tonne for net CO2 removal is possible. This achievement needs strong policy intervention/support but different financing systems maybe necessary for different technologies.