Feasibility study on the spread of NZEBs using economic in- 2 centives

Nowadays the environmental and energy issue has caught a lot of attention in the civil 12 buildings sector, leading to the emergence of new technologies and new targets, which include the 13 Net Zero Energy Buildings (NZEBs). However, despite the great response in scientific research, the 14 spread of NZEBs in Europe is quite limited. This is due not only to the lack of transposition of the 15 related European Directives into the various national legislations, but also to the high initial cost of 16 such high-performance buildings. The aim of this paper is to demonstrate how by resorting to fi- 17 nancial instruments, i.e., tax incentives, making an existing building an NZEB can be an achievable 18 goal. A suitable building energy dynamic simulation software has been used. The case study refers 19 to a villa located in Southern Italy and for which different energy retrofit strategies are proposed to 20 reach the NZEB target. For each case an energy and economic evaluation is carried out to evaluate 21 the feasibility of the interventions, exploiting the so-called "Super-Eco-Bonus 110%" incentive. The 22 main results highlight that among the various solutions, the greatest energy cost reductions are 23 obtained with the use of heat pump generators. Furthermore, the solution with the biomass boiler 24 allows to use a smaller number of photovoltaic panels to meet the yearly energy balance of the 25 NZEB