The article focused on energy poverty and its prevention among 258 clients of the Home Social Care Service in the town Zdar nad Sazavou in the Czech Republic. The old and dependent people who need daily assistance are the typical vulnerable group. The root causes of clients' vulnerability were studied. The research showed specific problems with data gaining in case of dependent people. The most significant factor for the ability to prevent or to reduce the energy poverty was found the client's age. The older person the more limits to avoid or to prevent the energy poverty. The second important factor was the contact with the family. The most appropriate tool to prevent energy poverty was found the information campaign tailored to old people and reflecting their specific needs and limits.