(27b) Atmospheric CO2 Predictions for Different CCS Scenarios Based on EIA Fossil Fuel Emissions Projections

An excel spreadsheet based model uses the equation ΔCO2 = 5.13 + E − 0.0177*CO2 to calculate annual increases in atmospheric carbon dioxide. In this equation ΔCO2 is the annual increase in atmospheric carbon dioxide in any year after 1750, E is the annual fossil fuel carbon dioxide emissions in ppm of atmosphere in that year and CO2 is the average January atmospheric carbon dioxide concentration in the same year. The model accurately calculates CO2 from 1750 to 1980. This is not surprising because the data used to derive the model came from this time period. It is surprising that the model calculates all CO2 values from1980 to 2019 within 1.4ppm of the NOAA measured values because this is outside the time period used to derive the model. Fossil fuel emissions are the only independent variable in this model. It is not necessary to include other carbon dioxide fluxes as separate items in the equation because some are taken care of by the two equation constants and others cancel each other out. Based on EIA projections through 2050, fossil fuel emissions, CO2 will be 482ppm by 2050. 58% of EIA’s projected emissions would have to be captured and sequestrated to maintain CO2 at its current level of 410ppm. This paper considers a novel atmospheric CCS process using calcium oxide.

The spreadsheet based model described in this paper is useful for predicting CO2 based on fossil fuel emissions data. To calculate 2019 CO2 from 1750 requires 270 consecutive iterations of the model starting with the 1750 CO2 of 277ppm. Three examples of the 270 iterations are: CO2 in 1751 = 277 + 5.13 + E in 1750 − 0.0177*277; CO2 in year n+1 = CO2 in year n + 5.13 + E in year n − 0.0177*CO2 in year n; and CO2 in 2019 = CO2 in 2018 + 5.13 + E in 2018 − 0.0177*CO2 in 2018. All values of CO2 after 1750 are calculated from the previous year’s calculated value. No interim corrections of CO2 based on measured CO2 data are required between 1750 and 2019. After 270 iterations the model calculates CO2 in 2019 to be 410ppm, which is the NOAA measured value.