The cost of DAC varies depending on the specific technology used, the size of the facility, and other factors. According to a 2018 report by the Global CCS Institute, the capital cost of DAC ranges from $100 to $600 per tonne of CO2 captured, with operating costs ranging from $50 to $100 per tonne of CO2 captured. However, the report notes that these costs are highly uncertain and could vary significantly based on a variety of factors, including the scale of the project, the location of the facility, and the availability of low-cost renewable energy.

Some companies that are developing DAC technology include Carbon Engineering, Climeworks, and Global Thermostat. These companies are working to improve the efficiency and reduce the cost of DAC technology over time.

The cost of carbon mineralization also varies depending on the specific technology used, the size of the facility, and other factors. According to a report by the Center for Climate and Energy Solutions, the capital cost of carbon mineralization ranges from $100 to $150 per tonne of CO2 stored, with operating costs ranging from $20 to $30 per tonne of CO2 stored.

Some companies that are working on carbon mineralization technology include CarbonCure Technologies, Blue Planet, and Solidia Technologies.

It's worth noting that both DAC and carbon mineralization are still in the early stages of development and commercialization, and the cost estimates provided above may change as the technology evolves and more projects are developed. Additionally, the cost of CCUS technologies may vary depending on factors such as the policy and regulatory environment, the availability of financing and incentives, and the degree of competition among technology providers.

I honestly believe that CCS underground will only ever reach small demonstration project scale due to the energy costs involved and the uncertainty of the integrity of the majority of large scale, ex E&P hydrocarbon reservoirs. Those with such integrity will most likely be used for Hydrogen storage. Large Scale industrial CO2 emitters require highly efficient CO2 capture methods, not currently available and the pressure/density properties of CO2 can be a pipeline engineers nightmare. So the hierarchy of risk control applies: minimise CO2 formation as carbon offsetting is just a political statement in my opinion and exists due to the absence of global, long term, reduction strategies.

https://ilar.ucsd.edu/_files/publications/studies/2010_carbon-capture.pdf

https://ilar.ucsd.edu/_files/publications/studies/2010_carbon-capture.pdf