Achieving near-zero carbon dioxide emissions from energy use: The case of Sri Lanka

Signatories to the Paris Agreement are to achieve net zero Green House Gas (GHG) emissions during the halfcentury to pursue the efforts limiting global average temperature increase by 2 degrees C compared to pre-industrial levels. This study models ambitious to challenging scenarios involving energy demand and supply side actions for energy system transition toward net-zero for Sri Lanka. To analyze these scenarios a least cost optimizationbased bottom-up type energy system model was developed from 2015 to 2050. A Business-as-usual (BAU) scenario and four countermeasure (CM) scenarios termed Plausible, Ambitious, Challenging, and Stringent were developed. Four different carbon tax rates were used to fathom the level of carbon tax needed to achieve net-zero emissions. The CM scenarios were formulated considering different technology options and policy measures such as the diffusion of efficient technologies, availability of renewable energy sources, use of cleaner fuels, the introduction of nuclear and carbon capture and storage technologies, and green hydrogen for power generation. The result of this study reveals that the stringent scenario which includes aggressive policy measures in both the energy supply and demand sectors, such as nuclear, and renewable energy for power generation, diffusion of efficient Enduse devices, fuel switching, including the introduction of electric cars, and increased share for public transport achieves the near carbon-neutral scenario at a carbon tax trajectory of 32 US$/tCO2 in 2020 and 562US $/tCO2 in 2050. The Net Energy Import Dependency (NEID) of the country decreases to 13 % in 2050 compared to that of the BAU scenario (65 %) under the near carbon neutral scenario, which is a positive sign from the energy security perspective.

Automated summary

Signatories to the Paris Agreement aim to achieve net zero GHG emissions and limit global temperature increase by 2 degrees Celsius. This study for Sri Lanka explores ambitious scenarios for transitioning to a net-zero energy system by 2050, considering various technology options and policy measures. The results suggest that aggressive policies in both energy supply and demand sectors, including nuclear and renewable energy, efficient end-use devices, and fuel switching, can achieve near carbon-neutral status at specific carbon tax rates.