Abstract
An electricity modelling study is presented to support the decarbonisation of the power sector in Mauritius. The gaps in literature that this study aims to address are the insufficient evidence of systematic modelling in the country's electricity transition strategies, outdated targets in existing modelling studies, limited long-term climate ambitions and the under-representation of the impact of vehicle electrification on electricity planning. Hence, a techno-economic optimisation model is developed to explore three long-term (2025–2050) scenarios in the power sector of Mauritius. Scenario A reflects the current policy ambition, aligning with the Nationally Determined Contribution (NDC) targets of achieving 60 % of renewable energy in the electricity by 2030. Scenario B models a pathway to achieve net-zero emissions in the power sector by 2050 and scenario C builds on Scenario B by incorporating widespread electrification of the transport sector. The potential of switching heavy fuel oils with alternative liquid fuels is also explored in all scenarios. The modelling is conducted using a mixed-integer linear programming optimisation tool, the DECarbonisation Options Optimisation (DECO2). Results indicate that carbon emissions drop by almost 50 % if coal is replaced with biomass. Furthermore, a 100 % renewable energy grid is achievable with alternative liquid fuels generating around 1200 to 1500 GWh of electricity. In the case of net-zero emissions, 28 % of electricity can still be produced using fuel oils only if negative emission technologies (NETs) are deployed. Additionally, the electrification of transport is found to have significantly affected the electricity generation capacity. While the modelled system can meet a demand from electric vehicles of up to 400 GWh per year by the year 2050, the flexibility of choosing between the technologies reduces and expensive generation options need to be deployed. This electricity system modelling study aims at supporting policy decisions in national electricity grid planning in Mauritius.