It transposes the RED II directive on renewable sources. For builders it counts twice: it imposes a minimum renewable quota on new buildings and major renovations, and it introduces renewable energy communities (CER), which allow energy to be produced and shared locally. The text has been heavily reworked: Legislative Decree 190/2024 moved the plant authorisation regimes out of it, and Legislative Decree 5/2026 transposed RED III into it.
It concerns the promotion of renewable sources: the quota obligation in buildings (new and major renovations), self-consumption configurations and energy communities, and the identification of suitable areas (art. 20). The plant authorisation regimes, originally here, have moved into Legislative Decree 190/2024. Many implementing decrees and regional powers supplement its application.
It transposes the RED II directive and sets the trajectory towards a renewable energy system. For buildings it does two concrete things: it imposes a renewable quota on new and renovated buildings, and it opens the era of energy communities.
For new buildings and major renovations, a minimum share of consumption (heating, cooling, domestic hot water) and a minimum renewable electrical power proportional to the footprint must be covered by renewable sources, preferably on site. It integrates with the 'minimum requirements decree' (D.M. 26/06/2015): without it, the energy check does not close.
| When | What |
|---|---|
| New buildings | minimum share of thermal consumption + minimum renewable electrical power |
| Major renovations | reduced share, according to the extent of the works |
| Where | preferably plants on site or nearby |
A CER is a legal entity in which natural persons, small and medium-sized enterprises, territorial bodies and local authorities — together with research and training bodies, religious bodies, third-sector and environmental-protection bodies — join to produce, share and consume renewable energy locally. Large enterprises are excluded, and for anyone carrying on a business the participation may not constitute their main commercial or industrial activity. The energy produced by a plant (e.g. rooftop PV) is shared among the members within an electrical perimeter, with an incentive on the shared energy. It is a paradigm shift: from the passive consumer to the 'prosumer' who builds a network.
The most frequent tension is between the push for renewables and the protection of landscape and heritage. The decree identifies the 'suitable areas' where installation is favoured (art. 20, still in force). The authorisation regimes themselves, however, are no longer here: since 30 December 2024 they sit in the Renewables Consolidated Act (Legislative Decree 190/2024), which repealed the procedural block of 199/2021 — art. 18(1) and (2), art. 22-bis, art. 23(1), art. 24(1), art. 25(1), (2), (6) and (6-ter), art. 38 and its Annex II. On constrained properties and areas, in any case, the landscape authorisation or the heritage office's opinion remain necessary: simplification does not cancel protection, it coordinates it.
D.Lgs. 199/2021 moves renewables from incentive to structure: it makes them an obligation in the design and a social infrastructure in the communities. For architecture it is a double mandate — technical (the quota in buildings) and civic (the CER) — and one of the grounds where declared sustainability and real sustainability are measured.
Where this rule shows up in past architect qualification exams — study the rule, not just the theme.
New buildings and major renovations must cover a share of consumption with renewables and install a minimum renewable electrical power; the obligation, previously in Annex 3 of D.Lgs. 28/2011, is now in D.Lgs. 199/2021 and is checked through energy performance.
An entity in which several users join to produce, share and consume local renewable energy, with an incentive on the shared energy; they remain connected to the public grid.
Natural persons, small and medium-sized enterprises, territorial bodies and local authorities — municipalities included — as well as research and training bodies, religious bodies, third-sector and environmental-protection bodies. Two limits matter: large enterprises may not take part, and for anyone carrying on a business the participation may not constitute their main commercial or industrial activity.
In many cases yes, with simplified procedures down to free building; but on constrained properties and areas the landscape authorisation or the heritage office's opinion is still required.
They are the areas the rules mark as suitable for installing renewable-energy plants, where the procedure is eased. Art. 20 of Legislative Decree 199/2021 provides for them and — unlike other articles of the decree — it was not repealed by the 2024 Renewables Consolidated Act: it was amended and remains the reference, read together with the ministerial decree on suitable areas and the regional laws that actually identify them.
It is a binding requirement tied to energy compliance; any technical impossibility must be justified and handled under the rules, not simply ignored.