Best Practice Energy Design for D’Ieteren Garage in Mont-Saint-Guibert

January 24, 2019


Client: D’Ieteren Immo
Period: July 2017- November 2017


3E has performed a study for D’Ieteren Immo, responsible for managing the real estate portfolio of the D’Ieteren Group (the largest service provider for motorists in Belgium). This project represents a best practice for the integration of renewables and Electric Vehicles readiness. D’Ieteren Immo wants to use one of its garages as a state of the art project to be future proof for the breakthrough of Electric Vehicles. As part of their sustainable strategy, their wish is that this electricity comes from the on-site production of green energy. An ambitious goal, as the electricity consumption will increase with 100% compared to business as usual. An extensive feasibility study was done by 3E regarding the yearly and hourly energy balance. Storage and grid balancing was done on an hourly basis. The ambition of the team was a “good yearly coverage”, meaning more than 80% of the electricity consumption is produced on-site with a minimum injection into the grid, or moreover an auto consumption of 70 – 90%. A cost benefit analysis of several technologies was made to reach this goal.

Considering the specific conditions of the site, the building characteristics, plot size and building orientation, the following technologies were proposed by 3E:

  • Rooftop Photovoltaic panels: The most commonly used technology for onsite building related renewable energy is rooftop PV. The position and type of panels needed to be optimized to obtain the best-case scenario. A total of 113kWp of rooftop panels were installed as an outcome of a detailed PV simulation on hourly data.
  • Building Integrated Photovoltaics: Building Integrated Photovoltaics (BIPV) are an aesthetic option for integrated solar energy on roofs and walls. The detailed simulation of the building took into account shadings and efficiency on an hourly basis. This study resulted in a total of 43 kWp solar cells positioned in the glazed roof of the canopy. This technology brings not only an aesthetic way of combining solar energy with daylight access, it also gives a strong green image to the company.
  • Mid-range wind turbine: Other possibilities for renewable energy are possible on a small building plot. Mid-range wind turbines offer an interesting load profile and production for Electric Vehicle charging points.

To achieve the goal of a yearly coverage, we needed to investigate the need for electricity storage. Therefore, 3E looked to the production and demand profiles and the possibility to use recuperated batteries.

On-site renewable energy production and storage solutions are always case specific. 3E strives to support architects, developers and investors to define the best-case scenario for each project type and location.