Techno-economic assessment of Local Energy Communities

The European Union (EU) has set ambitious targets and policy objectives to move towards a society featured by a high Renewable Energy Sources (RES) penetration, at least 32% share, and low GreenHouse Gas (GHG) emission, at least a 40% cut, by 2030. In the forthcoming energy transition, an increasingly key role is expected to be played by Energy Communities (ECs): a legal entity where different actors satisfy their energy needs by cooperating in the energy production, transmission and consumption. These medium-large scale installations help also to bring several benefits to the population, achieving unfeasible results on individual basis. ECs aim also at decarbonizing energy systems by promoting the distributed power generation and increasing citizens awareness, as they are actively involved in the decision-making processes. This thesis presents the techno-economic assessment of an EC composed by residential and commercial users, comparing its performances to a scenario where such buildings act as Stand-Alone (SA) prosumers. The work begins with the EC modelling, from the building shape to a methodology for the load profiles definition. Then, a retrofit takes place in each user: depending on the building, PhotoVoltaic (PV), Heat Pumps (HPs) and a gas-fed CHP engine coupled with an absorption chiller are installed. Simulations have shown that the EC strategy leads to self-consume 156 MWh more (an increase of 25%). The following step has been the development of a quantitative economic model for the feasibility study. To this aim, an exhaustive regulatory framework analysis is provided to understand the position of ECs. The Renewable Energy Directive (RED) issued by the EU aims at framing ECs from a regulatory point of view; this document contains some guidelines but operative indications still lack, as they are left to the Member States (MSs); the transposition of such directive is expected in 2021 for Italy. Waiting for such date, combining RED principles with Italian electricity market rules, three different regulatory frameworks have been defined for the comparison. Such frameworks differ in the mechanism through which energy is sold, choosing between the Exchange on Site (EoS) or the FER decree (the new Italian legislation about RES), the possible adhesion to the free market and the presence of possible incentives. Moreover, Sensitivity analyses on system and transport charges, required to the EC for the public grid utilization when energyis exchanged, have been carried out. The economic comparison provides the Net Present Value (NPV) and the Internal Rate of Return (IRR) for the SA and the EC configurations. Results have shown that the EC brings always to higher gains, up to 50% more, while the FER decree has turned out to be the best way to sell energy. Nevertheless, in every frameworks, the additional charges impact is not negligible: they appreciably reduce the difference between the two scenarios, making less attractive for investors and citizens an EC strategy. Therefore, policy makers have to properly transpose the RED principles into laws that make ECs truly beneficial: a correct regulatory framework is the basis for the large scale diffusion of ECs.