Integrated techno-economic assessment of heating electrification and decarbonization pathways in a remote First Nation microgrid

• Integrated assessment links heating transitions with islanded microgrid operation. • Electrification cuts emissions ∼48% but requires major PV–BESS expansion. • Biomass heating cuts heating emissions by 75% with moderate investment. • Optimization reveals trade-offs between cost, curtailment, and emissions. • Data-driven framework uses real microgrid data to capture system limits. Energy insecurity persists in many remote Indigenous communities in Northern Canada, where electricity is commonly supplied by diesel microgrids and space heating relies on imported fuels such as propane, resulting in high operating costs, logistical vulnerability, and greenhouse gas emissions. This study evaluates integrated pathways to improve energy security and reduce operational emissions in Gull Bay First Nation (Kiashke Zaaging Anishinaabek), a remote Ojibwe community in Northern Ontario served by an islanded photovoltaic–battery–diesel microgrid. Using measured microgrid and weather data combined with building energy simulations implemented through the TOOLS4Cities platform, three scenarios are assessed: (i) the current baseline system with propane- and wood-based heating, (ii) full heating electrification using air-source heat pumps coupled with photovoltaics and battery energy storage system expansion optimized via non-dominated sorting genetic algorithm II, and (iii) conversion to biomass boilers. The biomass scenario reduces total operational emissions by 19% relative to the baseline and decreases heating-related emissions by 75%, with an estimated discounted payback period of 11 years. Full heating electrification achieves the largest emissions reduction (approximately 48%) but requires substantial expansion of photovoltaic-storage systems and a high upfront investment in an islanded system, with discounted payback periods near 10 years under baseline fuel prices. Sensitivity analysis indicates that escalating fuel prices improve the payback of both electrification and biomass pathways. The study contributes an integrated system-level framework linking heating transitions with islanded microgrid dispatch constraints and photovoltaic–battery expansion planning, benchmarked against measured microgrid data to identify operational limitations often overlooked in purely simulation-based studies.