Energy performance of the Green Office® Rueil building

To cover its energy needs, Green Office® Rueil includes energy-efficient techniques and equipment in its design. Using renewable energy, the building produces more energy than it consumes for its operation.

Geothermal energy and thermo-active slabs

To produce heat and air-conditioning, Green Office® Rueil will use groundwater from the water table. The ground-source or geothermal heat pump system is tried-and-tested technology that produces heat and cooling from sources naturally present in the environment. The result is lower heating and air-conditioning costs

A very efficient system that satisfies daily thermal requirements: the thermo-active slab. Credits: Atelier Bilto Ortega

Together with the ground-source heat pump, the thermo-active slab system will meet most of the heating and cooling needs of the  Green Office® Rueil building. The system involves using concrete to store heat or cold. Pipes embedded in the concrete slabs in the building’s superstructure from the first floor to the sixth floor carry heat transfer fluid and ensure that the slab maintains a constant surface temperature all year round. Around 85% of the cooling energy required for the thermo-active slab system is supplied directly by groundwater.

Decentralised ventilation  

A decentralised ventilation system using individual comfort units captures air directly from the building’s façade. The units operate at low speeds to provide users with a very high level of thermal comfort.

These ventilation units will integrate CO2 sensors to tailor their operation to the building’s actual occupancy level.

Photovoltaic panels

The West building of Green Office® Rueil will feature 2,100 m2 of rooftop photovoltaic panels which will produce around 320,000 kWh per year.

Energy consumption is compensated by renewable energy production. Credits: Atelier Bilto Ortega

Going further than 2012 thermal regulations

Green Office® Rueil is targeting primary energy* consumption of 20.2 kWh of final energy per m² per year, 70% less than the threshold set by the 2012 thermal regulations!


Energy Performance Contract (EPC)

Under this contract, signed for the entire term of the lease, the building operator undertakes to guarantee the tenant all the operating and maintenance costs, as well as energy consumption and production levels, in accordance with predefined conditions of use and occupancy.

An energy management system provides an accurate analysis of the building’s energy consumption in order to control consumption in real time, 24/7. 

Software package to assist with EPC management 

Designed especially for the Energy Performance Contract (EPC) concluded with Green Office® Rueil, the SI@GO software application analyses the building’s energy production and consumption in real time in terms of energy use and location. 

SI@GO performs three main tasks:

  • records the building’s energy data every 15 minutes,
  • presents the data clearly and understandably to all stakeholders,
  • produces a monthly report, which is used in meetings to track whether commitments are being met under the EPC.