Integrated optimization for least-cost, low-emission electricity pathways: Evidence from Saudi Arabia

Abstract

This paper analyses least-cost, low-emission electricity pathways for Saudi Arabia over 2018–2040. Using the LEAP modelling framework, four supply pathways are evaluated under a common electricity demand trajectory reaching 640.2 TWh by 2040, requiring approximately 707.4 TWh of electricity generation after accounting for transmission and distribution losses. Reference Scenario (RS), Maximum Natural Gas Scenario (MNGS) and Sustainable Future Scenario (SFS) apply exogenously specified generation portfolios, while the Least-Cost Generation Scenario (LCGS) employs LEAP’s integrated optimisation to endogenously select the mix. Results indicate that LCGS delivers the lowest total generation cost (USD 34.7 billion in 2040) and the lowest emissions of 51.1 million metric tons CO 2 equivalent (MMtCO₂e), outperforming RS (USD 46.9 billion; 75.2 MMtCO₂e), MNGS (USD 48.6 billion; 71.9 MMtCO₂e) and SFS (USD 58.4 billion; 55.2 MMtCO₂e). For an identical demand outlook, an optimised portfolio reduces both system costs and emissions relative to business-as-usual and technology-biased pathways. The analysis provides transparent cost–carbon trade-offs for capacity-expansion planning and supports cleaner, more affordable electricity development consistent with long-term energy security and Vision 2030 objectives. Conclusions emphasise the value of integrated optimisation to guide the sequencing of investments while indicating that targeted renewables, calibrated gas and nuclear additions, and demand-side measures can jointly improve affordability and decarbonisation outcomes.