Verzuolo (Italy)


The Happening system has been running continuously since autumn 2020, providing heat in the heating season and domestic hot water to the utilities.

The Italian pilot project is located in Verzuolo in the region of Piedmont. The building contains ten homes in a climate with hugehog temperature differences between winter and summer.

Climatic zone (Köppen): Climatic zone (Köppen): Dfb (Warm-summer humid continental climate) ​

Weather characteristics: ​

  • Colder winters (average T in January: 0,3 ºC). ​
  • The warmest summers among the three locations, in which cooling needs may be important. ​
  • High temperature difference between winter and summer months. 

Building description

It has been renovated in the last fifteen years, with interventions on building envelope. The insulation level corresponds to 2006 regulations. It is a two-floor building (5 dwellings in each floor). The dwellings are 2 room apartments, from 32 to 42 m2​

Ownership: The ownership is private (single owner), while inhabitants are tenants.

Existing heating and DHW System: A centralized gas boiler supplies hot water for space heating and DHW of all the apartments. In the rooms, the heat emitters are fan-coils. 

Existing control and monitoring System: A control and monitoring system currently exist on the building. In each dwelling, ambient temperatures are measured and act on fan coils operation. An old thermal and electricity consumption meters is present, but currently decommissioned. It allows also to remotely visualize and control the heating system main parameters. A new BMS and measurement system will be implemented. ​

Building energy consumption

Space heating and DHW ≈ 50 MWh​

Electricity consumption ≈ 18 MWh 

What has been done

  • Installation of 10 kW photovoltaic system of 20 kWh electrochemical storage
  • Installation of 3 centralized heat pumps of 15 thermal kW each
  • Installation of a water-water heat pump for the production of domestic hot water of 11 thermal kW
  • Modification, in the technical room, of the pipes and equipment, to interface new systems, such as new pumps, two inertial tanks of 650 liters each, back-up system and new domestic hot water boiler for heat pumps
  • Installation, in the dwellings, of 25 micro-heat pumps to replace the existing fan coils: these are nr. 10 ceiling type micro-pumps and 15 horizontal micro-pumps, wall mounted.
  • Implementation of the automatic management and remote control system of the new systems, with thermal and electrical energy meters for the evaluation of the energy benefits.
Installation of PV system
The technical room in HAPPENING configuration, with the two inertial tanks
An example of a micro-heat pump installed inside the dwellings
Thermal energy meter
Electrical connections of the heat pump for DHW production
The PV system in place