Carbon capture technology for natural gas power plants: selection techniques and implementation strategies for a real-world scenario

Abstract

Although renewable energy solutions are improving rapidly, the majority of electricity is still generated by burning fossil fuels, including natural gas, which generate Greenhouse gases (GHGs). These GHGs have been linked to significant climate changes that are projected to have far-reaching impacts across the planet if emissions are not drastically reduced. While renewable energy sources are a part of the solution, thought must be given for how to reduce the emissions from legacy power infrastructure like natural gas power plants, since it is generally infeasible to completely abandon all of the current and in-development fossil fuel plants in favor of renewable technologies. One possible solution to utilize these large capacity plants while reducing their carbon dioxide (CO2) emissions is carbon capture and storage (CCS) technology. By capturing the CO2 that is produced by these natural gas facilities before it reaches the atmosphere, the overall emissions can be lowered significantly, while the power produced can still be provided to the communities that rely on it.

This thesis answers one overarching question: how can we determine the most preferred technology and implementation strategy for utilizing CCS to reduce the carbon footprint from natural gas electricity generation while continuing to meet ever-growing demand? To create a real-world scenario, this question was viewed through the lens of a realistic stakeholder: an electricity producer trying to navigate the complex environmental and regulatory landscape while making prudent fiscal decisions. A number of System Design tools were used to explore this topic. A novel, hybrid Design Structure Matrix (DSM) was created to select the most appropriate attributes to include in the tradespace utility function. Two tradespaces were developed to determine the most preferred CCS technology from a technical standpoint. Then, a flexibility analysis was conducted to assess the most profitable economic strategy for implementing the most preferred technology into a natural gas power plant project.

For the given stakeholder’s priorities and value drivers, the most preferred technology was a post-combustion capture using monoethanolamine (MEA). However, there were a number of technologies that were on the Pareto frontier and could have been equally good options, given alternative stakeholder requirements. The most beneficial strategy to implement this technology was to build in the optionality to retrofit CCS capability and then install the CCS facility 11 years after initial plant start up. This research proves that a tradespace is a viable tool for selecting the most preferred CCS technology, and a flexibility analysis is a prudent strategy for determining the economic value of a CCS-based project. Importantly, the ability to select the most preferred alternatives can be adapted to any stakeholder and CCS project by changing the priorities and value drivers utilized.