Lyseng, Benjamin Cal2025-10-012025-10-012025https://hdl.handle.net/1828/22824This dissertation models the decarbonisation of Alberta’s power grid, transitioning from primarily coal-fired generation to delivering net-negative emissions. Three key stages of the transition are analysed using optimisation and simulation methods: the transition from coal to natural gas under carbon pricing, integration of 80% variable renewable energy (VRE) using power-to-gas (PtG) for long-duration energy storage, and the operational implications of direct air capture (DAC) for achieving negative emissions. In the first study, carbon pricing is found to accelerate emissions reductions, especially through coal-to-gas switching. The second study demonstrates that PtG can support an 80% VRE system by reducing VRE capacity and curtailment through long-duration energy storage. In the final study, DAC operation is shown to be closely tied to the marginal low-carbon generator. Overall, this work provides robust modelling and insights for regional decarbonisation strategies.enAvailable to the World Wide WebEnergy system modellingOSeMOSYSDAC (Direct Air Capture)Power-to-GasAlberta gridThesisB. Lyseng, A. Rowe, P. Wild, J. English, T. Niet, L. Pitt, Decarbonising the Alberta power system with carbon pricing, Energy Strategy Reviews, Volume 10, 2016, Pages 40-52, ISSN 2211-467X, https://doi.org/10.1016/j.esr.2016.05.001B. Lyseng, T. Niet, J. English, V. Keller, K. Palmer-Wilson, B. Robertson, A. Rowe, P. Wild, System-level power-to-gas energy storage for high penetrations of variable renewables, International Journal of Hydrogen Energy, Volume 43, Issue 4, 2018, Pages 1966-1979, ISSN 0360-3199, https://doi.org/10.1016/j.ijhydene.2017.11.162