A case study for energy issues of public buildings and utilities in a small municipality: Investigation of possible improvements and integration with renewables

This manuscript summarises the results of a project concerning the energy consumption of public buildings and utilities and the evaluation of the most effective and feasible ways to save energy in Certaldo, a small township in Tuscany with approximately 16,000 inhabitants. The energy analysis highlighted a specific partitioning of electric and thermal energy for final use. For example, more than 60% of the electricity consumption of the town is for street lighting, which is still uses obsolete and environmentally problematic lighting technologies, and more than 13% for lighting public schools. With respect to heat utilities, more than 60% of natural gas consumption is for heating public schools and 18% is for heating sport/athletic facilities. The partitioning of energy consumption introduced a list of requalification measures focused on specific areas: each area has an energy saving potential and specific feasible energy requalification technologies in addition to the possible introduction of suitable renewables. The selection of the proposed interventions was based on the results of model simulations, municipal urban regulations and prevailing trends resulting from a survey of municipalities that are the same size as Tuscany. The type and impact of these interventions were also in agreement with the trends found in different international contexts.In the final part of this paper, some instruments and considerations regarding the evaluation of the return on investment (ROI) for investments in energy bill reduction are presented.Although few data are available in the literature about actions to improve energy efficiency in the public sector of small municipalities, the comparison of energy consumption of Certaldo with that of bigger towns with similar climate conditions showed a reasonable proportionality to population and size of the urban area. Thus, the methodology and the examined solutions could be considered a representative case study and a starting point for municipalities with a similar size and number of inhabitants.Finally, a curve of profitability for investments in energy efficiency of the administration was constructed. It can be extended, at least in a first approximation, to similar cases.

► Energy issues of buildings and utilities owned by a small municipality are assessed.
► An overview of heat and electricity consumption of public buildings and utilities is carried out.
► The potential of PV on roofs of public buildings and improvement of streets lighting are evaluated.
► Some possible retrofitting of school buildings and sport facilities are evaluated.
► The results have several general aspects, replicable to other small towns in that size range.