The world's first energy positive office building, Elithis Tower, has opened in Dijon, France. Designed by Arte Charpentier Architects, the design and construction of the 10 story building was a conceptual challenge by Thierry Bievre, the General Director of Elithis Engineering. Surpassing net-zero, the building utilizes solar panels, recovered emissions, and solar shading to minimize solar heat gain. The building also employs over 1,600 emission-analyzing sensors to continuously monitor and display energy usage to the occupants. Surplus energy is fed back into the grid. Surprisingly, at 54,000 square feet and costing only 10 million, the office building is reasonably priced compared to typical office buildings of similar size.
According to the design firm Skidmore Owings and Merrill (SOM), energy positive buildings are the result of performative design, where four specific goals are engaged; reduction, absorbtion, reclamation, and generation. Whereas reduction and reclamation deal with the efficient use and re-use of energy available, absorbtion is the act of harvesting other available energy streams into the building. "Following the example of nature, don't shed water, absorb it." Of course, with the efficient use and re-use of energy, and the maximizing of available energy streams and technologies, the ability to generate positive energy and other potential effects becomes possible.
Pearl River Tower, the design for a skyscraper in China is another example of positive energy producing buildings but at a larger scale. Not only will the Pearl River Tower return energy to the grid, but due to it's size and efficiency, several floors of rentable office space were actually added to the design at no additional cost. The building height and form channel the prevailing winds through large openings in the mechanical floors that contain energy harnessing wind turbines. The louvres on the southern facade, which act as both solar shade and light shelf, have integrated photovoltaics that power internally mechanized shades on the same facade. The opposite facade is constructed as a double skinned curtain wall that forms a thermal barrier between the exterior and the interior, and ventilates vertically. The heat and moisture that is trapped and allowed to rise naturally is removed at every other floor level and is used in the building's dehumidification system.
Imagine several Pearl River Towers grouped together in an urban area. Each building, connected by these infrastructural systems, workng their own day job, providing physical space for day jobs, but producing energy at the same time. If connected, this network of super-efficient buildings could themselves be integrated into the local power grid and act as both infrastructure and power plant. By producing and distributing the surplus energy locally to their immediate surroundings, the buildings can replace the traditional infrastructure which is externally produced and delivered. Power generated off-site, which typically involves the consumption of fossil fuels or nuclear reaction, is inefficient and expensive due to production methods and the need to send power great distances through service lines. The need for large power plants and lengths of inefficient infrastructure is drastically reduced. The buildings themselves serve as producer and supplier, not to mention the effect of increased community interaction, education, and awareness of power needs and methods.
Elithis Tower seen on Inhabitat. Images via Arte Charpentier Architects. Pearl River Tower images via SOM.