N. Sunny, N. Mac Dowell
Imperial College London,
United Kingdom
Keywords: industry, decarbonization, hydrogen, carbon capture, BECCS, DACCS, renewables, modelling
Summary:
Relative to the power sector, progress in the decarbonization of the industrial sector has lagged significantly and requires concerted attention. Industries rely on carbon-intensive fuels such as coal, fuel oil, and natural gas for their operations, resulting in substantial quantities of greenhouse gas emissions. Hydrogen (H₂) and carbon capture and storage (CCS) technologies have promising roles in these sectors due to their ability to provide affordable solutions using familiar technologies. However, the necessary rate of deployment of H₂/CO₂ infrastructure, its regional dependencies, and its interplay between storage, and renewable resources are poorly understood. Moreover, strategies to decarbonise this sector have generally been developed in isolation based on sectoral archetypes, which overlooks synergies in co-locating investment with other sectors. In this contribution, we present a spatially explicit roadmap of investments to generate a net-zero industrial “cluster” using mathematical optimisation. Additionally, the economic, environmental, and system-wide implications of adopting post-combustion CO₂ capture, fuel switching with hydrogen and electricity, and offsetting CO₂ through negative emission technologies are investigated. The mathematical model comprises a mixed integer linear program based on the Resource Technology Network (RTN) framework introduced by Pantelides [1]. The models have been developed with a comprehensive description of all infrastructure components within electricity, biomass, H₂, and CO₂ value chains. Technologies such as biomass gasification, and combustion with CCS, direct air capture with CCS, auto-thermal reforming with CCS, natural gas combined cycle power generation with CCS, renewable electricity generation, and water electrolysis are compared to identify suitable strategies to mitigate industrial emissions, given the distribution of incumbent infrastructure and the availability of storage resources. We find that investments in post-combustion CO2 capture are necessary to tackle process emissions, but the supply of steam and power will vary depending on the cost-effectiveness of zero-carbon energy vectors such as hydrogen and electricity. Moreover, investments in technologies such as bioenergy with CCS (BECCS), or biohydrogen with CCS (BHCCS), deliver CO₂ avoidance by providing electricity or hydrogen with a zero-carbon footprint to displace a fossil-based supply, whilst simultaneously removing residual CO₂ emissions generated in industrial clusters. The insights from two “real world” industrial clusters in the United Kingdom will be used to discuss the value of different CO₂ abatement technologies, and their corresponding demand for resources such as natural gas, emission offsets, renewable electricity, and CO₂ storage. The analysis identifies strategic elements of investment (i.e., identifying first users, oversizing pipelines, modularising process units) within the cluster to enable the timely expansion of new technologies and infrastructure to achieve net-zero emissions. [1] C. C. Pantelides, “Unified Frameworks for Optimal Process Planning and Scheduling,” Oper. Res., 1994.