The adoption of domestic photovoltaic systems has in numerous studies been proven to be influenced by peer effects and socioeconomic factors such as income, age, gender, education etc., which has led to irregular spatial installation patterns. Only a few studies regarding domestic solar thermal systems indicate that the same effect exist for this technology. However, the interaction between photovoltaic and solar thermal deployment and the similarities or differences in socioeconomic factors have not been investigated in detail so far. This study identifies the most prominent socioeconomic factors behind both domestic photovoltaic and solar thermal adoption in three different municipalities in Sweden, based on a complete set of 452 photovoltaic and 359 solar thermal collector systems installed until 2020, which was identified and classified by a method that uses machine learning and aerial imagery. A moderate (absolute Pearson correlation, |ρ|, > 0.3) to intermediate (|ρ| > 0.5) correlation between photovoltaic and solar thermal penetration was found on demographic statistical area level, and several of the previously reported influential socioeconomic factors for domestic photovoltaic installation were confirmed also for domestic solar thermal adoption in Sweden.