Degrés Bleus is an innovative system developed by the Lyonnaise des Eaux water treatment and sanitation firm which allows to recover and reuse the heat contained in waste-water. This heat is then used for heating and cooling purposes in buildings. By using this technology, building can reduce up to 60% of their GHG emmissions generated by heating and cooling needs. The system offers a solution to reduce energy expenditure, while reducing the impact of human activity on the environment.
The Lyonnaise des Eaux water treatement and sanitation firm has developed a system allowing to recover the heat contained in waste water, within its water distribution and recovery network. When recovered, this heat is then reinjected into the heat generation and disribution systems within buildings, resulting in a considerable reduction of energy needs.
The wasterwater which flows underground is a source of renewable energy which been traditionally unutilised. Its temperature usually fluctuates between 12° and 20° year round, making it a source of excess heat during the winter and a means of cooling the air during the summer.
The recovery of the excess heat can be carried out within water collectors which are part of the water distribution and sanitation network, as well as from purified water obtained from water treatment stations. Once collected, this heat is integrated in to the main heating circuit by means of a heat pump.
By using this technology, it is estimated buildings can reduce up to 60% of their greenhouse gas emissions by reducing energy needs for air and water heating. The system offers the possibility to reduce energy costs in light of increasing energy prices and the implementation of the recently adopted carbon tax in France. Degrés Bleus therefore offers several potential benefits:
• Covering from 50 to 80% of total heating and cooling needs
• Reducing GHG emmission by approximately 300 tons for a building with 250 residential units
• Projects may be financed in part by the French Energy and Environemental Energy’s (ADEME) heat fund, making them potentially less expensive than traditional heating solutions
Barriers and Drivers
The introduction into the market of this particular technology has been mainly driven by the increasing demand for cost and energy-friendly heating and cooling solutions. The market demand for such solutions has been spurred by the rise in energy and commodity prices, increasingly strict regulation concerning building standards, as well as by fiscal deterents such as the carbon tax recently implemented in France. Changing consumer behaviour has also played a part in bringing alternative heating and cooling technologies to the market. This trend is illustrated by the increasing number of new housing projects marketed as being environmentally friendly, notably through the obtention of green labels such as LEED or HQE (High Environemental Quality, Haute Qualité Environnementale).
As is the case with most innovations introduced in the construction field, the main barriers relate to the difficulties encountered during the verification and demonstration process of the technology. Testing the solution in real life conditions often proves to be difficult, while the need for solid evidence demonstrating the actual gains brought about by the use of such technology is key to market introduction and diffusion. In addition, the installation cost for this type of technology is higher than that of traditional heating solutions, which represents a considerable obstacle to market takeup.
The installation of the Degrés Bleus system is estimated to result in up to a 50% reduction of energy needs, bringing about important economic savings for end users. Despite the economic gains that may result from the use of the system in terms of energy consumption, the installation and operation costs of the system remain higher than those of traditional heating and cooling solutions, making it less appealing to potential users (e.g. local government administrations).
The system offers solutions in favour of sustainable development by:
• Reducing energy expenditure
• Contributing to the fight against global warming and the reduction of GHG emissions
• Promoting the use of local renewable energy sources
• Producing green energy and reinforcing energy autonomy
• Protecting and improving the living conditions of the general population
Degrés Bleus allows to cut GHG emissions generated by buildings from the use of traditional energy sources for heating and cooling pruposes.