Estimating CO2 Seqestration Costs For Climate Scenarios

Climate scientists have proposed various "carbon budgets" for limiting the future temperature increase. For example, the National Academy of Sciences recently estimated that "no more than approximately 230 GtC may be emitted in the future to remain under this [2° C] temperature threshold". It is generally accepted a significant amount of carbon dioxide will need to be captured and sequestered in order meet any carbon budget that limits the temperature increase to 2° C or less, but there has been hardly any attention paid to the expected sequestration costs associated with meeting a carbon budget. 

The purpose of this Web site is to explore the various factors that contribute to the sequestration costs and to provide rough costs for variety of fossil fuel emssion scenarios. For a given carbon budget and fossil fuel emissions scenario, the process to estimate the carbon dioxide removal costs is as follows:

  • A fossil fuel emissions scenario will determine the "total fossil fuel CO2 emissions", the "CO2 emissions captured", and the "net CO2 emissions"
  • The estimated emissions from "land use changes" and "natural emission" are added to the "net CO2 emissions", giving the "total CO2 emissions"
  • If the "total CO2 emissions" are greater than the carbon budget, the difference will need be captured and sequestered by some sort of "direct air capture" (DAC)
  • (For this analysis, CO2 captured by agricultural processes and afforestation are subtracted from the "natural emissions" and included in the "natural emissions" total)
  • Carbon dioxide removal costs are computed based on expected costs/ton C for CCS and DAC

Click here for an estimate of the carbon dioxide removal costs for the NAS 230 GtC carbon budget.
Click here to view a form where the carbon dioxide removal costs are estimated based on values that you can specify for the carbon budget, fossil fuel emissions, etc.

Ultimately, the carbon budget depends on the following factors:

  • The target temperature
  • The climate sensitivity
  • The warming caused by factors other than CO2
  • The amount of CO2 that ends up in the atmosphere from net CO2 emissions

Click here for an example that shows how the carbon budget for Dr James Hansen's 1.0° C target temperature can be estimated.
Click here for an estimate of the carbon dioxide removal costs for the carbon budget for Dr James Hansen's 1.0° C target temperature.
Click here to view a form for calculating the carbon dioxide removal costs which includes carbon budget estimates for various target temperature increases, climate sensitities, and non-CO2 radiative forcing