57 Direct Air Capture Direct air capture (DAC) is a nascent technology that uses similar sorbent/regeneration cycles to post-combustion capture, but on the much lower concentrations of CO2 in the air. Pilot demonstrations have recently reached 4000 tons CO2/year, at costs of $600/ton CO2 when powered renewably, and the cost is expected to decrease significantly over the next decade. DAC has a TRL of 6-7, but the current cost and scale make it less effective than post-combustion capture for the emissions MIT currently produces. The implementation of DAC will significantly depend on projected improvements in overall plant footprint: current contactors are modular and roughly the size of a shipping container, but additional infrastructure for purifying and compressing the CO2 requires significantly more space. If the technology develops near the end of the CUP’s useful life, MIT may consider repurposing post-combustion capture space and infrastructure for DAC. Once separated, DAC has the same sequestration potential as postcombustion capture. Biological Capture MIT currently has over 1300 acres of densely forested land in Westford, MA. This forest is estimated to sequester approximately 5,000 tons CO2/year with little intervention. With proper accounting, verification, and protection, this forest could be included in MIT’s GHG accounting for as low as USD $10/ton. Risk and Innovation The level of risk associated with deploying carbon capture varies primarily with storage technique – plant matter and inert solids pose very little risk to workers or the surrounding community. However, geological storage poses more risk, as it requires drilling at least 800 meters below ground and managing gaseous of supercritical CO2, which may leak from pipelines or improper sequestration. The public is likely to perceive the storage process as risky, and while they may see it as a net benefit, prefer any storage activities occur far from where they live (Pianta, Rinscheid, and Weber 2021). Additionally, many decarbonization activists see industrial carbon capture as a method of prolonging fossil-fuel dependence, and it will likely be seen as unfavorable to continue use of the natural gas CUP even with CCS unless significant efforts are also made towards atmospheric capture. However, to our knowledge, post-combustion capture has not been implemented on a college or university utility plant, and the challenges associated with post-combustion capture at this relatively small scale mean that a successful implementation would show innovation. Additionally, atmospheric capture is a relatively nascent technology, and significant advancements in the field are likely to attract positive public attention.
RkJQdWJsaXNoZXIy MjA2MzQ5MA==