Analysis of thermal control and heat accounting economic convenience in typical Italian housing unit and climatic zones.

The present paper deals with the application of the recent Italian energy regulation (Legislative Decree 102/2014, Italian transposition of Energy Efficiency Directive 2012/27/EU) which states as mandatory the installation of heat accounting systems for each housing unit in buildings served by central heating, cooling and domestic hot water systems, except in case of technical impossibility and economic inefficiency. Building energy need depends on the following main parameters: insulation level, climatic conditions which affects both transmission and ventilation heat losses, operating time characteristics, plant efficiency. If energy need is low, the related economic saving is low compared with the installation costs of thermoregulation and heat accounting systems. The aim of the present paper is to statistically study the economic advantage linked to the application of the Legislative Decree 102/2014, considering a typical Italian dwelling served by a central heating system. It is statistically possible that, in warmer climatic zones from A to D of the Italian territory, the installation of thermoregulation and metering of winter thermal energy doesn't have any economic advantage. On the contrary, an economic return is very likely in cooler climatic zones E and F. The cost-benefits analysis is carried out according to the UNI EN 15459 standard in terms of SP and NPV indicators.