To Grid or Not to Grid : Viability of Standalone Distribution Networks in the Far North

This paper summarizes the work of two studies (2016 and 2017) into whether electricity grid connection is economically beneficial when solar, or solar and wind generation is locally installed to an island community in the south of Finland. Three types of customer groups were considered: summer cottages, free-standing energy houses and a camping site. Approximated consumption time series based on measured data and simulated time series data for wind and solar production based on rigorous statistical modelling were used to make a sober assessment of the viability of the scenarios. It transpired that, based on 2016 costs for the solar-only option, and 2017 costs for the solar and wind option, that it is more economical to make a 7 km MV feeder connection to a primary substation than invest in the backup generation and storage necessary to provide supply to even the summer-only demand scenarios. The methodology is outlined with reference to full reports available online.