Energy and economic simulation of a renewable energy community applied to a new generation ultra-low temperature district heating and cooling network

Department of Energy, Politecnico di Milano, IT

^* Corresponding author: michela.romagnosi@polimi.it

Abstract

The work describes the energy and economic simulation of a renewable energy community with a social purpose applied to a residential and commercial new district in Milan, the eight buildings of which are connected to a new generation low temperature district heating and cooling network. The system is designed considering two substations for each building, each one providing heating and cooling load profiles by means of heat pumps, and an energy centre that exploits groundwater to extract and dissipate compensating heat at low temperature. Some roof mounted photovoltaic panels, owned by the district residents, cover the electricity needs resulting from the net metering of the renewable energy community. The members of the energy communities are in fact the multifamily buildings of the district acting as prosumers and some fragile families from the surroundings as simple consumers. The economic profits, represented by the subsidies coming from the diffuse self-consumed shared energy and from sold overproduced electricity, are distributed among the members to guarantee, first of all, an economic help against energy poverty to fragile families, and, secondly, a short pay-back-time for photovoltaics. Therefore, the operational strategy of the district network is optimized to maximize the shared electricity and the relative economic benefit by shifting, when possible, the electricity demand when the solar production is available. Finally, three different profit distribution mechanisms are analysed. The added value of this work is the evaluation, by means of a specific case study analysis, of the feasibility of an electric energy community from an economic as well as a regulatory point of view under current legislation.