Demo case in Bellpuig, Spain (IMAGE) Eurac Research Caption The spanish Demo-Case is a multi-family building with three floors and 15 dwellings. The researchers calculated that the primary energy demand was reduced by 60 percent thanks to the prefabricated façade, the ventilation system with heat recovery and photovoltaic panels. Credit Agència de l'Habitatge de Catalunya Usage Restrictions Photographic material is available to the press on the condition that sources are clearly indicated and images are exclusively published in reference to specific press release or report content. Images may only be used for non-commercial purposes and may not be resold or passed on to third parties. License Original content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.