Austria’s first CO2 neutral house with increased daylight factor.
The victorious from a 2008 competition held by the company emerged Velux project is part of a European program called Model Home 2020th To achieve the set goal of high CO2-neutrality of the entire planning process from the Danube University Krems and the IBO was accompanied. The design responds in a specific manner to the difficult situation of the land and its potential uses to the maximum. The living area is on an incised atrium connected to the garden. The open roof space of the bedroom floor is dominated by a series of skylights, the daylight from all sides lead into the interior.
With only 6 months of construction from groundbreaking to opening in October 2010, the timber will be implemented in record time.
Heart of the building services concept is the so-called energy roof. Two oriented to the southwest roof surfaces, which in its entirety with 48 m² photovoltaic panels and solar panels fitted sin 8 m². Along with the geothermal heat pump is produced in 30 years, more energy, as was the production and operation of the building by then necessary. From this point on, the building generates energy that is surplus.
Juri Troy’s architectural design is a direct response to the home’s surroundings. Sunlighthouse is located on a steep, partially-shaded slope and faces southeast towards the Vienna woods. The nearby mountains cast dramatic shadows over the valley, so the living area features high roof windows that bring light to the centre of the room.
The kitchen and dining areas face southwest and feature numerous roof and façade windows, all positioned to provide amazing views and maximum passive solar energy gain. And besides providing an unusually high level of daylight, the windows also act as a central design element in home.
Sunlighthouse takes advantage of sunlight to provide its residents with optimal conditions for their health and well-being. Researchers at Danube University Krems evaluated the home’s daylight levels and found that it has an average daylight factor of at least five percent in all living spaces.
The roof and façade windows were all strategically placed to provide stunning views, maximum passive solar heat gain and natural ventilation. These many windows ensure daylight levels are balanced throughout the home’s two storeys. In fact, Sunlighthouse’s total window area is equal to 42 percent of its floor area, so very little artificial light is needed during the day.
Automated, intelligent control of the home’s windows is the primary source of ventilation in spring, summer and autumn. In the winter, however, Sunlighthouse uses a mechanical ventilation system with heat recovery. The home uses no energy for cooling, but the stack effect of the windows, night cooling and awning blinds on the windows ensure Sunlighthouse has a comfortable indoor climate throughout the warm summer months.
Sunlighthouse aims to keep energy consumption to a minimum without sacrificing the family’s comfort or standard of living. With its ultra-efficient brine heat pump for heating, thermal solar collectors for hot water, photovoltaic (PV) solar cell system for electricity, and energy-efficient household appliances, the house is powered exclusively by renewable energy.
The home’s PV solar cells and solar collectors actually generate more energy than the house uses. This means that after 30 years the home will have generated as much clean energy as was created in its construction, making it truly carbon neutral.
Real time Energy balance
Sunlighthouse is located in Pressbaum, Austria. In it are installed various types of VELUX roof windows. On the model you can see the current balance of each roof window. The immediate energy balance is calculated as being current incident solar energy minus the heat loss through the window. If the energy balance is greater than zero, the window is adding energy to the building.
The intention of this model is to illustrate the windows’ energy balance at this specific moment and thus illustrate how the sun contributes to the energy balance of the building. This contribution is considerable, even on an overcast day, making the window an actual heat source.
The Sunlighthouse is Austria’s first CO2-neutral single-family house with an exceptionally high daylight portion. Two southwestwards oriented roof surfaces entirely equipped with 43 m² monocrystalline photovoltaic panels and 8 m² solar collectors. Together with the geothermal heating pump and direct solar energy output of the windows in 30 years the house will produce more energy than it would have been necessary for constructing, transporting and running the house. As a consequence from this point of time the house will start producing an energy surplus (active house). The project demonstrates that – even in Austria where difficult terrains occur quite frequently – buildings without an „ecological footprint” are possible.
Project name: VELUX Sunlighthouse
Location: Pressbaum, Wien-Umgebung, Austria
Type: Single-family detached home
Completion Year: OCTOBER 2010
- 2010 State Prize for Environment and Energy Technology
- 2010 Active Architecture Award
- 2011 Vorarlberg Wood Construction Award
- 2011 Chicago Athenaeum International Architecture Award - International Award
Client / Owner / Developer: THE VELUX GROUP
Architects: Hein-Troy Architekten
Project Director: Yuri Troy
Engineer: DANUBE UNIVERSITY KREMS AND THE INSTITUTE FOR HEALTHY AND ECOLOGICAL BUILDING (IBO).
Text Description: © Courtesy of Hein-Troy Architekten, THE VELUX GROUP
Images: © Adam Mørk