Optimizing Renewable Injection in Integrated Natural Gas Pipeline Networks Using a Multi-Period Programming Approach
Author:
Ogbe Emmanuel12, Almansoori Ali2ORCID, Fowler Michael1ORCID, Elkamel Ali12ORCID
Affiliation:
1. Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, Waterloo, ON N2L 3G1, Canada 2. Department of Chemical Engineering, Khalifa University of Science, Technology and Research (KUSTAR), Abu Dhabi P.O. Box 2533, United Arab Emirates
Abstract
In this paper, we propose an optimization model that considers two pathways for injecting renewable content into natural gas pipeline networks. The pathways include (1) power-to-hydrogen or PtH, where off-peak electricity is converted to hydrogen via electrolysis, and (2) power-to-methane, or PtM, where carbon dioxide from different source locations is converted into renewable methane (also known as synthetic natural gas, SNG). The above pathways result in green hydrogen and methane, which can be injected into an existing natural gas pipeline network. Based on these pathways, a multi-period network optimization model that integrates the design and operation of hydrogen from PtH and renewable methane is proposed. The multi-period model is a mixed-integer non-linear programming (MINLP) model that determines (1) the optimal concentration of hydrogen and carbon dioxide in the natural gas pipelines, (2) the optimal location of PtH and carbon dioxide units, while minimizing the overall system cost. We show, using a case study in Ontario, the optimal network structure for injecting renewable hydrogen and methane within an integrated natural gas network system provides a $12M cost reduction. The optimal concentration of hydrogen ranges from 0.2 vol % to a maximum limit of 15.1 vol % across the network, while reaching a 2.5 vol % at the distribution point. This is well below the maximum limit of 5 vol % specification. Furthermore, the optimizer realized a CO2 concentration ranging from 0.2 vol % to 0.7 vol %. This is well below the target of 1% specified in the model. The study is essential to understanding the practical implication of hydrogen penetration in natural gas systems in terms of constraints on hydrogen concentration and network system costs.
Funder
Department of Chemical Engineering at the University of Waterloo, Canada Research Chair Tier I—Zero-Emission Vehicles and Hydrogen Energy Systems Natural Sciences and Engineering Research Council of Canada (NSERC), Discovery Grants Program
Subject
Energy (miscellaneous),Energy Engineering and Power Technology,Renewable Energy, Sustainability and the Environment,Electrical and Electronic Engineering,Control and Optimization,Engineering (miscellaneous),Building and Construction
Reference68 articles.
1. (2022, December 23). U.S. Energy-Related Carbon Dioxide Emissions, Available online: https://www.eia.gov/environment/emissions/carbon/. 2. (2022, December 23). Natural Gas Explained: Natural Gas and the Environment, Available online: https://www.eia.gov/energyexplained/natural-gas/natural-gas-and-the-environment. 3. Aruna, C. (2022). Investigating the Role of Natural Gas and Hydrogen in a Future Integrated Energy System. [Ph.D. Thesis, University College Dublin]. 4. Maroufmashat, A., and Fowler, M. (2017). Transition of Future Energy System Infrastructure; through Power-to-Gas Pathways. Energies, 10. 5. Sani, S.A., Maroufmashat, A., Babonneau, F., Bahn, O., Delage, E., Haurie, A., Mousseau, N., and Vaillancourt, K. (2022). Energy Transition Pathways for Deep Decarbonization of the Greater Montreal Region: An Energy Optimization Framework. Energies, 15.
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