Renovation of DHW production in twelve social dwellings

The DHW production was ensured by individual electric water heaters until now. The replacement of these by a collective heat pump induces a 50% reduction on the electric bill due to DHW production.

Lessons learned 

  • Before renovating, the primary energy consumption due to DHW production was about 75kWhep/m².yr.
  • Final objective for ep consumption is 24 kWhep/m².yr.

Key facts

BuildingHeat Pump and Source
LocationSoisson, FranceNumber of HP1
ConstructionretrofitInstalled power11kW
Heat distributionunderfloor heatingOperation modemonoenergetic
Heated area841 m²Heat sourceambient air
No. of apartments12FunctionDHW only
level of insulationModelAtlantic
Heating sytemDomestic Hot Water
Heat demand– kWh / (m²a)DHW demand29kWhep/m².yr. in 2013
Heating
temperature
°CType of systemcentral
Heat supplyDistrict HeatingMax. temperature65 °C
Circulation system yes (thermodynamic loop)
Other information

Description of the technical concept

The system consists of:

  • A 11kW Atlantic® air-to-water heat pump
  • Two storage tanks with 750l capacity each
  • An Atlantic® thermodynamic loop heater

The system functioning is based on an accumulated mode: the storage tanks allow to store the daily DHW needs. Then, the heat pump produces heat during the night, for eight hours continuously.

Even if the outside air temperatures are lower during the night, this type of operation offers advantages in terms of performances:

  • After a day of draw-offs, the volume of water in the tanks is completely cold

-> optimized COP

  • An operation during night allows to benefit from lower electricity tarrifs

FR005 Soisson