Nowadays an oil crisis is going on. The impact of rising fuel prices of all energy sources, except renewable ones is destructive. It is an opportunity and a challenge to promote renewable energies by application of the existing technology and simultaneously by intensive research to lower costs and improve technology for more compact installations, less expensive materials and longer life. In this paper an attempt is made to evaluate water shortage and water needs in some of the dry Aegean Archipelagos islands and analyze the possibility to install solar devices, mostly solar distillation units, individual or small community size. A preliminary analysis is also made to assess the feasibility of waste heat as well as heat from refuse incineration.