Gathering local data to assess energy efficiency and reconfirm estimates – example of El Brull

Author: Maryke VAN STADEN, Communications Officer, Energy for Mayors, Germany - Email

El Brull, a Spanish village of 225 inhabitants, is working on its Sustainable Energy Action Plan (SEAP) with the support of the Diputació de Barcelona (DIBA) (Province of Barcelona) - a Covenant Coordinator since 2008 and partner of the Energy for Mayors project. DIBA has developed a specific methodology based on the CoM guidelines to assist Municipalities in its territory when conducting their assessments.

This methodology includes energy assessment inspections of municipal buildings and facilities. El Brull, as a very small community, has few municipal buildings. As a practical approach to base estimates on the Agència Local de l’Energia del Consell Comarcal d’Osona, conducting the SEAP assessment inspections, resorted to door-to-door visits of homes in this village. This opportunity not only helped to get estimates of energy used in buildings but could also be used to have direct contact with important stakeholders – local citizens.

All visits to the “sample” dwellings chosen to calculate average energy consumption for residential buildings resulted into ad hoc reports, with a set of conclusions including specific measures to improve energy efficiency. The data gathered proved to be particularly interesting for the Province of Barcelona, reconfirming that data related to residential sector can be quite inaccurate, as for instance, heating oil data are not to municipality scale therefore rough estimates are often necessary.

In El Brull, energy consumption was higher than expected due to size of dwellings (average size above 350m²) and to local climatic factors. A residential building consumes 192 kWh/m². The average consumption rises to 357 kWh/m² for the service sector. The reports show that about 80% of energy consumption is for heating, while the rest is mainly electricity used for lighting. In addition, all visited buildings used oil or liquid gas for heating, resulting in an average GHG emission of 14 tonnes of CO₂ for heating and 3 tonnes of CO₂ related to electricity consumption.

Each report was also delivered to the building owners during an information session to raise awareness and stimulate energy efficient behavior in the community. Among the measures identified to reduce emissions are: increasing building insulation, encouraging energy efficient behavior, changing lighting system, replacing heating system with biomass – to result in estimated energy savings of about 48 kWh/m² (37kg CO₂/m²) with an estimated cost of 108€/m².