Office Bouygues Construction

In 1988, after two years of construction, the new headquarters for Bouygues Construction officially opened for business. Named Challenger, the complex became a technological showcase for the late 20th century. Twenty years later, Bouygues wants Challenger to remain a modern marvel, and the company has initiated a very ambitious project to make it possible. For instance, one of the myriad of high-reaching goals is to reduce energy consumption on site not by a factor of two or three, but rather an eyebrow-raising factor of 10.

To match Bouygues’ objectives to significantly reduce energy footprint, new air-conditioning system had to be the most energy efficient amongst those in the market. The site is equipped with a heat pump on dry probes – fitted with 75 vertical sensors buried 100 meters deep – and four temperature recording probes. The system works by using the soil temperature, which is collected by means of a liquid flowing in a closed circuit. In addition to geothermal technology, the thermal loop is fed by five adiabatic coolers that use the air and water of the phyto-purification station to cool the water loop.

Automatic variable water flow control : a world premier LG Multi V Water was chosen, and its strong performance was proven via onsite testing In order to make it functional, it was necessary to improve the flow of the loop. When competitors didn’t success in making the flow rate vary between 50 and 100, the LG solution optimized it and offered a wider range between 35 and 100. The result is a 71 in water savings compared to conventional control.

Power, Performance, Savings and Durability have all been achieved: with impressive COP of 5.4, water consumption was saved by more than 70％ The results were more than convincing: in the summer of 2011, after a 56-day test, water consumption was shown to have decreased by more than a third.