Conventional energy supply often implies energy intensive transport to make fuels available at the place of their final use. It is argued that reducing the costly import of fuels would particularly benefit islands as they are mostly at the periphery of economic regions with their scope of competitiveness being limited. Here renewable forms of energy can enter the playground. In narrowing the focus on the residential heating and electricity sector of the town of Lusk, Ireland, it is stated that the technical potential of roof-integrated photovoltaics and a wind turbine would amount to 948.516 kWh/yr. This corresponds on a theoretical basis to 45% of the residential electricity requirement. Solar collectors could make up for 27% of the annual hot water requirement of the households. As a human dimension the behavioural potential is determined and contrasted to the technical one. A high potential-low adoption paradox has to be identified. The complexity of the process of adopting solar energy on the house level is outlined by setting results of psychological research in context to the findings in Lusk. Conclusions are presented that provide hints for increasing self-sufficiency of Lusk＇s energy supply.