Economic appraisal of energy efficiency renovations in tertiary buildings

The EU, through its energy policy, has established a renovation rate of 3% for public buildings. This activity has a key role in achieving European targets regarding reducing energy consumption and greenhouse gas emissions. Moreover, the promotion of building renovations would reduce energy dependence and unemployment in the EU. The present work is aligned with the recently updated EPBD in the energy policy through an economic evaluation of energy renovations of eleven tertiary buildings. These buildings belong to three Spanish university campuses, and most of these buildings were built under the previous Spanish building code, which was enforced between 1979 and 2006. While revisions to the envelope are typically cost prohibitive, active measures can achieve a significant reduction in energy consumption and energy costs. The investment is recouped in 1.1-6.7 years for a new lighting installation and 0.7-7.7 years for a natural gas or biomass boiler. For the optimal combinations, typical reductions in primary energy consumption range between 12% and 48%. In the current scenario of limited economic resources, the data provided in this work can be used to prioritize expenditures in energy renovations from environmental or economic approaches.