Inaugurated with great fanfare in September 2017, Delta Green, a 4,608 m² building, became the first energy-independent office building in France thanks to energy production greater than user consumption.
“This result is obtained by producing energy using photovoltaic panels, heating/cooling on geothermal probes and by geocooling (11 drillings at a depth of 150 m allowed the installation of this system where the water circulates in a closed circuit, from the earth to the living spaces), by storing the energy produced to meet the building’s consumption during periods of energy deficit via a hydrogen station (a first in France) and finally, by raising occupants’ awareness of their energy impact by making them responsible for the proper use of their workplace,” explains Alain Raguideau, president of Galeo, a real estate developer.
A successful bet and also rewarded by the “Green Solutions Awards” of the Construction 21 network in 2018 which highlight exemplary buildings, neighborhoods and infrastructures that contribute to the fight against climate change. Delta Green thus obtained the National Sustainable Construction Grand Prix France. The jury was won over by its complete and balanced approach: an architectural form which promotes natural lighting and comfort and thermal solutions which play on both the passive (it is labeled PassivHaus) and the active.
There is thus a heating/cooling system using active slabs and heat pumps on vertical geocooling probes and three fields of photovoltaic panels on the roof, in shade.
In total, annual solar production is estimated at 520 MWh of primary energy when the annual consumption of the building (all uses) reaches 476 MWh.
