Energy utilization for distributed thermal production in rural areas: A case study of a self-sustaining system in Spain

Self-sustaining systems are considered by researchers, policy makers and investors to be one of the most interesting technologies in the world. The proportion of energy being derived from biological sources is increasing due to processes for converting wood biomass. In rural areas in Europe, bioenergy can effectively alleviate energy dependence on external energy resources for green energy development. An applied bioenergy study was conducted in Ezcaray, Spain, a forested village representative of rural areas in cold climate zones in southern Europe. The present study aims to evaluate and use existing forest resources and assess their thermal potentiality and replicability in remote areas via self-sustaining systems for distributed thermal production. Knowledge gaps and technology options for assessing and meeting sustainability criteria are analyzed. The implemented methodology considers a combination of mass, energy and costs from the source to the bioenergy heating system, and it assesses the techno-economic feasibility of such systems against boilers using different fuels. Two proposals were studied, namely, starting a pellet mill for the thermal system market and replacing existing boilers with biomass in self-sustaining systems. The first proposal is profitable, with a selling price equal to or higher than 146.04 €/t. In the second proposal, the non-renewable primary energy consumption in the studied households was between 13- and 15-times higher with fossil fuel boilers than with biomass boilers. In both cases, thermal systems in rural areas may effectively alleviate dependence on non-renewable energy to increase green energy use in Europe by 2020.