Arte Charpentier put something back into the grid with their positive energy building
Elithis Engineers called upon renowned architecture practice Arte Charpentier Architectes for close collaboration. Together, the group rose to the challenge to create a building which marries aesthetics, urban integration, comfort, energy and environmental performance. Today, the Elithis Tower is the most positive energy building in the world, in terms of energy and environmental impact.
Greenhouse gas emissions from the Elithis Tower are six times less than emissions from a classic commercial building. The new tower has the possibility to become a true laboratory of energetic experimentation equipped with more than 1,600 sensors to meticulously examine and analyse energy and emissions. Scientists, researchers and universities will be invited to visit the building and benefit from the information collected in this environment.
Daily energy consumption of the Elithis Tower will be posted and displayed on a special sign, offering full transparency in greenhouse emission and important elements. The Elithis Tower, truly the new generation in building design and construction, proves that it is possible to create an aesthetic, clean, energy efficient building that costs the same as it does to create traditional buildings.
"On this project, the engineer was located more upstream than usual. We put our research and development at the service of the work, with a simple but effective objective: more grey matter for less grey energy. Thus, we were ingenious engineers and broke the barriers which existed between our two professions."
"We treated this building as an urban object in an emblematic site. We conducted a lot of research, simulations and studies to achieve a result which is sparing in energy and which fits in harmoniously with the urban environment. In the end, it is a small object, but a real jewel."
Towards positive-energy architecture?: the awakening of contemporary environmental challenges determines new fashions in the design of buildings. This mobilization is all the stronger since residences and offices account for 25% of CO² emissions and 42% of the total consumption of energy in France. It therefore quickly appeared essential to architects and town planners to adopt a radically different procedure, avoiding the generally very strong fragmentation between various spheres of activity, to have a harmonized general reasoning.
This awakening, on certain points, considerably modified the work of the architect. Thus, by working in collaboration and not in constant competition with engineers, the Elithis project aimed to develop a new 'global multi-partnership approach.' With numerous techniques having to be developed and tested, it was necessary to work in tandem. Throughout the research process, 'the architect convinced by the images and the engineer by the graphics.'
Any experimental and innovative project must indeed be accompanied by a questioning of our development models and our behaviour. Thus, if the technical and technological answer is essential, it also appeared necessary to develop an ecological and good citizen approach, whether in the architectural design or in the education of the behaviour of users of the building.
An emblem of sustainable design: the Elithis tower is located on a site emblematic of the dynamism of the town of Dijon, in the heart of the ZAC (mixed development zone) 'business park', between the auditorium and the conference centre. This site, near the town centre, constituted a decisive element in the design of the project. Indeed, the reflection on the participation of this building in an exceptional district from an economic standpoint, strongly engaged the thoughts of the architect.
Its site at the crossroads of important business districts was to enable the town of Dijon to be at the head of an aesthetic development in innovative architecture respectful of the environment. For all that, the site was, according to the architects, 'rather curious.' With a much reduced size - 600 sq m - it was located in 'a very messy' urban complex, between the massive shapes of the auditorium and the conference centre. This project thus required an in-depth reflection on the urban and landscaped integration of the building.
A singular object: the architects' choice was consequently to treat the building as an object with the idea of making it unique within the urban landscape. This choice was based on the observation that there was a lack of urban consistency on the site. In the Elithis programme, there is no phenomenon of unified urban facades with a duplication of buildings offering a similar architectural handwriting. The Elithis tower cannot cling to any pre-existing element and is therefore relatively isolated. This treatment as an object therefore can be seen as a link with the argument, traditional in architecture, between singular and plural. The singular and plural determine the relationship between the building and the town: either a building is treated as an object, in a radical break with what surrounds it, such as an icon, or it falls within an urban dimension, in continuity with the fabric and morphology of the city. For Elithis, the architects designed a building that is an object, a true 'jewel' for the town of Dijon.
An exemplary building: this project wishes to impose itself as a figurehead of responsible architecture. The semantics of positive energy then appeared as a flagship element in the design of a building which aims to be the most virtuous possible. It was truly necessary to 'join in the race' to carry out this project. By energy plus, it is necessary to understand a building which produces more energy than it consumes for its functioning. The Elithis tower is thus a symbol, made to encourage other experiments.
For all that, there was no marked desire to make the architecture of the building itself an ostentatious 'manifesto' for sustainable development. The challenge was not to make a building which talks of energy plus through 'external signs' of sustainable development, such as visible solar panels or clearly displayed wind turbines. The result, on the contrary, gives a building of an apparent simplicity, ovoid shaped, resolutely compact and abundantly glazed.
The most outstanding visual element is undoubtedly the coppered solar shield which surrounds the essence of the facade of the building. Designed in the shape of a metal lattice, it embodies the investment of Elithis and Arte Charpentier Architectes in the fight against global warming.
Its asymmetrical shape is based on a study of the sun's rays at various times of the day, depending on the seasons and on a model of the shadows cast by surrounding buildings. To produce this shield, the architects and engineers worked initially from solar studies, to optimize the design and treatment of the shield, with the idea of avoiding overheating linked to summer sunshine and to maximize the contributions of solar energy in winter.
Thus, the building has the characteristic that it needs practically no heating and minimizes the use of thermodynamic ventilation. It is the flexibility of the building itself which was thought out with a system of 'controlled natural ventilation' making it possible to control the temperature of the building with external air.
By using the difference between the internal and external temperature, it is possible to move back the fateful threshold of thermal discomfort. The sun is then filtered but without hiding visibility and light. As a result, with this project the architects and engineers wanted to break with the generally-accepted idea that an 80% glazed building was strongly energy intensive. The free solar contributions that it allows are assets both in terms of natural lighting and heating of the building.
Another innovation lies in the choice of 'nomadic' lighting of the offices. The architects have increased the proportion of socket-outlets dedicated to lighting for each user, allowing the deployment of auxiliary lighting at the work station and transferring in an individual and nomadic manner the need for artificial lighting. Users will then be able freely to make the choice of standard lamps integrating the technology of gradation and detection of presence. Rather than large highly energy consuming ceiling lights, the work of the interior designer concerned individual furniture, made up of standard lamps provided with LED and of an efficient design.
An experimental project: the building will be the subject of experimentation for a period. Elithis engineering intends to become a real laboratory for positive-energy buildings. Scientists, professionals and students will therefore be regularly invited to take part in improving research, by exploiting the various data on the site or from their buildings. Moreover, a notice will be installed at the foot of the building, to give a permanent indication of the energy produced and the energy saving made in terms of greenhouse gases. Even the electric power used for office automation will be entered. By producing energy on the site, this building will be independent in terms of energy and will no longer discharge CO². By informing residents and passers by, this notice will serve as an example to the city.