A field study was conducted through interviews on offshore islands in Taiwan to investigate the energy usage of local residents. A comparison of household appliance usage in mainland Taiwan with that on the offshore islands revealed that, overall, the most commonly used household appliances are steam cookers/rice cookers, water dispensers, and washing machines. For other household appliances, Levels 2 and 3 offshore isles have lower use penetration rates compared with those in mainland Taiwan and on Level 1 offshore isles, particularly for the use of computers. By contrast, the use penetration rate for chest freezers on Levels 2 and 3 offshore isles is high, and each household has one or more freezers on average. This appliance is not a commonly observed household product in mainland Taiwan or on Level 1 offshore isles. Furthermore, because of the government policy, every household on parts of Level 2 offshore isles and on all Level 3 offshore isles has a fixed monthly charge of electricity. The transportation of liquefied petroleum gas is also inconvenient, and the gas price is slightly higher, leading to the tendency of residents to consume excessive amounts of electrical energy, which does not correspond with the aim of the government to conserve energy and reduce carbon emissions; thus, the relevant authorities' review and improvement on energy consumption on Levels 2 and 3 offshore isles are required. OPEN ACCESSSustainability 2015, 7 6653