Bouygues Construction has partnered with the city of Grenoble in France to build an experimental block of 90 apartments aiming for 100% self-sufficiency in energy and water use, where energy storage and rainwater capture systems should allow the flats to run autonomously 24/7.
The building will be constructed as part of the Presqu’Ile development zone in the heart of the Grenoble’s £1.1bn new EcoCité project and is the first demonstrator of Bouygues’ ABC (Autonomous Building for Citizens) concept, developed in collaboration with architect Valode & Pistre.
ABC aims to achieve self-sufficiency in energy, in terms of electricity and heating, without the need for residents to modify their patterns of energy usage.
The 90 apartments will use a combination of low power equipment and innovative power management systems such as presence detectors to cut electricity consumption by an average 20% compared to a recently built apartment block. In addition, a passive-designed building envelope and heat recovery from waste water will help reduce heat consumption by an average 30%.
ABC aims to achieve self-sufficiency in energy, as well as water and to optimise waste management
Power will be provided by a combination of renewable energies, such as solar panels, wind turbines, hydro-turbines or biogas, supplemented by power from energy storage facilities intended to offset the irregularity of renewable energies. This will involve the batteries for short-term storage, or hydrogen for long-term storage, while thermo-chemical salts and phase change materials can be used for storing heat. Together these solutions are expected make it possible to achieve self-sufficiency in energy.
To achieve self-sufficiency in water without residents having to modify their behaviour, water-efficient appliances will be installed to reduce consumption by around 40% per resident, from an average of 120 litres per day to 75 litres.
In addition, rain water capture systems will direct water into reservoirs where it will be filtered and treated to make it drinkable. Rain water will be recycled several times for other uses and technologies such as microfiltration and UV lamps will be applied to make the water reusable.
The ABC concept also aims to reduce the amount of non-recycled waste by two thirds. As part of this, “putrescible” waste such as bio-waste, food-soiled paper and card and sanitary products, which constitute around 30% of domestic waste and sewage, could be methanised and converted to energy in the form of biogas. Residue from the methanisation process can also be recovered for use as compost. These measures will result in a reduction in household garbage generated annually to 100kg per person.
Once built, the performance of the apartments will be closely monitored for a period of five years and support provided for residents.
EcoCité is designed to become a showcase for the city of tomorrow. Construction of the first 500 homes in the project will be launched in late 2014, 30% of which will be for social rental occupancy and 10% for social ownership. The ABC projects aim to become a technological showcase of French know-how whose concepts and components can be easily replicated and exported, particularly to countries that have no existing infrastructure networks but need to provide housing without increasing their energy dependency or exhausting their water resources.
