Emission Scenarios for a 100% Renewable Faroese Power System A System-Level Life Cycle Carbon Intensity Assessment Towards 2040

Abstract

The Faroe Islands have set an ambitious target of transitioning towards a fully renewable electricity system, but the climate impact of different technology pathways remains uncertain. This thesis assesses how alternative energy system configurations influence the system-level life cycle carbon intensity of the Faroese power system in 2040. Five scenarios were evaluated using outputs from a Python for Power System Analysis (PyPSA) based energy system model: a Base scenario, a Tidal scenario, an Offshore wind scenario, a Vehicle-to-Grid scenario and a Combined scenario including all investigated technologies. For each scenario, the system-level carbon intensity was calculated by combining technology-specific life cycle GHG emission factors with modelled installed capacity and annual electricity generation. Storage infrastructure, including battery energy storage systems and Vehicle-to-Grid (V2G), was included as a separate system-level contribution. The results show that the climate impact of a 100% renewable power system depends strongly on the available technology mix. Among the CO2-constrained scenarios, the Combined scenario achieved the lowest system-level carbon intensity, at 11.0 g CO2- eq/kWh, followed by the Tidal scenario at 33.8 g CO2-eq/kWh. The Base, Offshore wind and V2G scenarios showed much higher carbon intensities, ranging from 56.6 to 57.5 g CO2-eq/kWh. A key reason for this difference is the amount of battery storage required to balance the variable renewable generation. The Combined scenario required significantly less stationary battery storage, resulting in a much lower storage-related climate impact. The findings imply that achieving a low-carbon renewable electricity system is not only a matter of replacing the fossil generation, but also of integrating complementary technologies that reduce storage requirements, curtailment and capacity overbuilding. Tidal power appears especially valuable in the Faroese context due to its predictable generation profile, while V2G mainly contributes flexibility rather than direct emission reductions. Overall, the results highlight the importance of whole-system planning when assessing renewable energy transitions in isolated power systems.