Decarbonization of the heating sector from a system point of view: The case study of the Lombardy Region.

This work aims at defining the optimal technological mix which minimizes the total
cost of the energy system in 2030 in the Lombardy region, in northern Italy. The goal is reached
through a bottom-up model built on a linear optimization problem considering different technical
and economic inputs and constraints. Civil sector is one of the sectors to focus on for the
decarbonization process. Different areas, types of buildings and thermal systems are included in
the model to consider the peculiarities of the available solutions in each context. The overall
technological mix is constraint by a CO2 emission limit. For the civil sector the more the emission
is constrained, the higher is the penetrations of electric heat pumps, coupled with envelope
retrofit, (10% of the total thermal energy demand) and of district heating (18%), while natural
gas boilers decrease (66%). Biomass boilers reach a maximum penetration of 29% in mountain
areas. District heating is relevant in areas with available sources (max 29%). Natural gas boilers
coupled with air conditioners have an important role and they reach a maximum penetration of
89% in certain areas. Electric heat pumps are quite homogeneous through the areas for residential
buildings.