Determining the optimal azimuth for solar-ready buildings: Simulating for maximising the economic value of solar PV installations in Lapland, Finland

This study investigates the impact of building orientation on the economic feasibility of residential rooftop photovoltaic installations in Arctic climatic conditions, aligning with the European Union's advocacy for region-specific 'solar-ready' buildings. The research uses a novel combination of 3-dimensional modelling, solar simulation, and comprehensive economic analysis, offering precise, location-specific recommendations for optimising solar PV installations in Arctic regions. The study demonstrates how orientation and discount rates significantly influence the system's economic viability. The economic analysis for solar PV installation orientations ranging from 0° to 359° and discount rates from 3 to 7% reveals grid parity in the Levelized Cost of Electricity and positive Net Present Value for all azimuths for discount rates in the 3%–6% range. Furthermore, results show favourable Discounted Payback Periods for azimuths in the 70°–270° range at a 3 % discount rate and in the 120°–200° range at a 5 % discount rate. The findings reveal that the optimal azimuth range for buildings should be considered before zoning municipal areas to maximise economic performance. Economic simulations indicate an optimal azimuth 156° for the region, deviating significantly from the recommended 172°. The article underscores the importance of region-specific optimisation over general guidelines, representing a key contribution to solar energy planning in Arctic conditions.