What’s a Green Office®?

Guaranteed building charges for a Green Office® building

Green Office® positive-energy buildings use a real-time energy management solution to offer users a guaranteed level of building charges.


Green Office® Meudon has  the first Energy Performance Contract (EPC)  signed with private players. Architect: Ateliers 115 Architectes; Credits: Eric Sempé

Energy Performance Contract

For its Green Office® buildings, Bouygues Immobilier has developed an innovative energy management software application for its Energy Performance Contract (EPC) which enables the building’s operator to guarantee the user a stable level of operating charges based on predefined conditions of use.

Green Office® Meudon is leased with an EPC and Green Office® Rueil‑Malmaison plans to include one. EPCs enable tenants to control their operating costs. Under an operation and maintenance contract covering the term of the lease, the building operator guarantees the following: 

  • all operating and maintenance costs, as well as any services predefined with the tenant (reception, security, hygiene and cleaning, etc.),
  • levels of energy production and consumption, in accordance with predefined conditions of use and occupancy (peak and off-peak times, temperature, workforce numbers, etc.).


 An EPC is planned for the future Green Office® Rueil, whose East building will house Unilever’s head office. Credits: Jean-Michel Wilmotte

SI@GO, a tailored software application for EPCs

In 2010, Green Office® Meudon was the first building leased with a private-sector Energy Performance Contract (EPC). For this, Bouygues Immobilier developed an innovative software package dubbed SI@GO. 

Central to the building’s energy management system, SI@GO performs three tasks: 
  • records the building’s energy data in real time, i.e. 50 million data items per year for Green Office® Meudon,
  • 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.


Centralised management system - SI@GO

Feebate scheme

Each day, the energy management software monitors any overruns and savings in real time on all items previously identified. If needed, quick adjustments can be made under the system, which also includes a feebate scheme.

  • If the contractual level of energy consumption is overrun because of poor management by the operator, the latter covers the additional fees.
  • If the user is responsible for the overrun because they did not follow the predefined conditions of use, they cover the additional fees.
  • If consumption is lower than projected for under the contract, the rebate is shared between the user and the operator.

Guaranteed building charges: a major competitive edge

In a tight property market, offering a guaranteed level of building charges is a major attraction for potential tenants, who may sign longer leases if the rent includes fixed, guaranteed building charges. For investors, it also reduces the vacancy risk.