Solution Phase 2:Zero Emissions
Eliminating Carbon Dioxide Emissions
In order to eliminate global carbon dioxide (CO2) emissions, we will implement a comprehensive system of carbon capture and sequestration. All of the emissions from point sources will be eliminated completely or captured and sequestered via point source capture (pre-combustion capture, oxy-fuel combustion capture, post-combustion capture) technologies. A system of air capture will be used to target emissions derived from non point sources. At the beginning of this stage, about 30.11 Gt of CO2 will need to be sequestered each year to eliminate emissions. By the end of this stage, because the ability of natural processes to absorb atmospheric CO2 is decreasing under the stress of excessive anthropogenic emissions, we will need to sequester approximately 33.7 Gt of CO2 (Sabine 2004: Khatawali 2009).
Of the world’s anthropogenic CO2 emissions, approximately 50% are from point sources, particularly from fossil fuel-burning power plants. Three different methods will be used to capture these emissions: pre-combustion, post-combustion, and oxy-fuel combustion. Existing power plants that are capable of being retrofitted will be retrofitted with post-combustion capture technology. Those plants which are not compatible with the post-combustion retrofitting process will be rebuilt integrating post-combustion capture technology. New coal-burning power plants will integrate a pre-combustion or oxy-fuel system into their construction. The other 50% of emissions, nonpoint source emissions, will be captured using air capture plants.
Captured carbon will be stored using various sequestration methods in different areas around the world. The primary methods of sequestration that will be implemented in this plan are seabed storage, saline aquifer storage, in situ mineral sequestration, and sequestration as a result of oil and gas reservoir sequestration. Over the seventy-five year period, from 2025 to 2110, 850 Gt of CO2 will be stored each in saline aquifer sequestration (seabed aquifer sequestration and terrestrial saline aquifer sequestration). In situ mineral CO2 sequestration will store 300 Gt of CO2 and oil and gas reservoir sequestration will sequester 270 Gt of CO2. Seabed and terrestrial saline aquifer storage, while more expensive, have much greater capacities for storage than in situ mineral CO2 sequestration and will be used to store the majority of the captured carbon.
The captured CO2 will be cooled, condensed, and pressurized and then transported to the nearest sequestration location by specially adapted pipelines. Inland power plants and air capture plants will transport their captured emissions via pipeline primarily to saline aquifers storage sites and in situ mineral processing plants. Coastline plants will use the seabed as their primary form of storage, transporting their captured carbon to specially built ports where the liquid CO2 would be loaded on tankers to be taken out to sea.
Additionally, the process of biochar burial will be implemented, which further sequesters CO2.