GASOKOL collectors heat Europe's largest fully solar industrial property


HABAU takes its production fully solar. Founded over 100 years ago, this pioneering company uses 100% solar energy with intelligent thermal component activation in its new precast part production facilities. 1,410 m2 of GASOKOL solar collector surface make sure of that.

HABAU is among the top 4 players in the Austrian construction industry. The company's forward-looking and globally active management approach can also be seen in the energy solution rolled out for the new precast part production facilities at the Perg location. This project is a trendsetter for the industrial sector.

Planning and construction – professional and fast

‘Many of the production facilities in Perg were getting on in years. Some of the existing facilities were too low and too narrow for future requirements. This necessitated an adaptation of the production conditions at the HABAU precast plant. After careful planning and financial considerations, constructing a new building with a total surface area of 7,700 m2 proved to be the most sensible solution. We made the investment in order to sustainably improve our competitiveness and increase productivity at the Perg location, and to improve both plant safety and working conditions for plant employees,’ says HABAU Managing Director TR Dipl.-Ing. Anton Karner.

Four buildings – wider, longer and higher than the existing stock – were newly built from the ground up. The first building was able to commence production after only a month of construction. In addition, Europe's most modern partially automated carousel production facility for large-scale concrete elements has been commissioned at the new HABAU precast plant in Perg.

Building with the sun

In addition to settling functional production process issues, HABAU also dealt with the issue of optimising lifecycle costs, and thereby with the issue of sustainable plant operation.

Management readily seized on fully solar activation of building structures for heating the production areas as the answer. 1,410 m2 of gigaSol OR solar collectors made by the upper Austrian solar specialist GASOKOL cover the heating needs of nearly 100,000 m3 of space. Fully solar activation of building structures ensures a very pleasant indoor working climate at HABAU year-round. ‘This 100% solar project is the largest of its kind carried out to date in Europe. The solar thermal energy recovered is also used as process heat,’ explains Erwin Gattringer, GASOKOL's Managing Director. GASOKOL's Competence Centre for solar thermal systems in Saxen provides solutions for up to 100% solar fractions in all system sizes.

The integrated planning approach with a focus on the client and with the executing firms as partners is an essential element of fully solar building structure activation. The close cooperation, the resulting high degree of prefabrication of structural elements as well as the involvement of regional enterprises enables more rapid construction at reduced cost.

Using this innovative solution, HABAU saves around 500,000 kilowatt hours of fossil fuel energy annually, avoiding CO2 emissions of around 190 tonnes per year. This means that HABAU is assuming a leading role in the field of climate and environmental protection.

HABAU is aware of its responsibility

HABAU is the first and until now the only company in the Austrian construction industry that has taken a stance on social, ecological and economic responsibility by migrating to fully solar activation of building structures. More than 35,000 m3 of structural precast parts are produced annually at the Perg location alone. The HABAU GROUP has around 4,300 employees. 

Fully solar project goal - details

The project's stated goal was to construct HABAU's production facilities for precast concrete parts using low-energy construction on the basis of a highly ambitious technical energy concept, including fully solar heating without any additional heat sources and the use of surplus solar energy as process heat for drying the hollow core slabs and for pre-heating the carrier oil.

The use of fully solar building structure activation, and with it uniform temperature control of the floors in the production facilities, makes for a comfortable and healthy working environment. In addition, the project yields annual savings of around 500,000 kWh of fossil fuel energy. For this project alone, this corresponds to a reduction in CO2 emissions of 190 tonnes per year. With this model project, HABAU is assuming the mantle of ecological leadership in industrial construction, and raising awareness of resource stewardship issues among both employees and customers.

’Fully solar heating of HABAU's production buildings combined with 1,410 m2 of collector surface and intelligent building structure activation makes us unique in the industrial sector,’ says Harald Kuster, who planned the energy solution. ‘The solar heating system in conjunction with building structure heat storage technology provides fully solar heating of production facilities with a total surface area of 7,700 m². From April to October, the excess energy generated is used to support the manufacturing processes. This ensures optimal utilisation of the collector surface year-round,’ Kuster adds.

Execution, features and innovative aspects

The large-surface solar thermal energy collector system made by the upper Austrian solar specialist GASOKOL constitutes the core of the building's heat supply, and is divided into three fields of 470 m² each. High-efficiency pumps and high-performance solar heat exchangers store the solar energy in the central buffer store. During the winter months, the buffer store is applied to the concrete heat reservoir to bring it to an optimal temperature level. 

In the HABAU project, the heat reservoir corresponds to an active thermal mass of 2,560 m³ of concrete with a total weight of 6,145,000 kg. To this mass is added the passive thermal mass of the exterior and intermediate walls, with a total weight of 1,090,000 kg. This results in a reservoir capacity of 10,200 kWh. 

The solar collector system is entered into extreme high-flow operation during the heating season. This produces particularly high collector field yields, as well as an extraordinarily high degree of efficiency in the low return flow temperatures from the concrete heat reservoir. Outside of the heating season, the system is entered into low-flow operation. This enables the high temperature level that HABAU requires in the production of precast concrete parts. The integration of the buffer store into the overall heat distribution system also results in a significant improvement to the existing central heating system's hydraulics.

A high-grade insulation concept coordinated with the energy concept results in a level of thermal protection that is extraordinary for industrial buildings of this size. All energy-relevant circuits were equipped with heat meters for use in the internal monitoring system. This guarantees high-quality hydraulic balancing of all systems for the most energy-efficient possible use, as well as precise data evaluation and energy accounting. System monitoring functions provide exact representations of energy flows, thereby further improving the overall energy efficiency.

The use of local construction materials and domestic products reflect ecological, economic and social responsibility, and yields gains in terms of efficiency and project sustainability. This fully solar project can serve as an impetus for rethinking practices and taking responsibility when carrying out industrial projects. 

Fully solar heating with intelligent building structure activation – buildings that practically heat and cool themselves

The thermal energy recovered by the solar collectors is stored in structural concrete. Compared to traditional heat sources, as a thermal reservoir concrete guarantees a very comfortable indoor climate – including during extended periods without much sun. 

Depending on the building standard and user profile, a solar fraction of up to 100% can be used to supply heating energy requirements. This means that no CO2 is emitted for space heating and hot water heating, and that there are no energy costs. Any surplus energy can be fed into an existing district heating network, transferred to nearby properties or used as process heat.

100 % solar-heated buildings – for private, commercial and industrial use

Solar building structure activation is equally attractive for private, commercial and industrial properties. 

Solar activation of building structures ensures consistent room temperatures and an optimal indoor climate during winter and summer alike. The drafts and localised air turbulence characteristic of conventional heating systems do not occur, as the concrete thermal mass ensures uniform temperature stratification throughout the space. Solar activation of building structures is extremely energy efficient and can be used for both heating and cooling applications. 

How solar activation of building structures works

The solar system collects solar thermal energy and transports it into the heating buffer. From there the heat is fed into the building structure activated as the thermal reservoir. The energy is absorbed by the thermal mass and delivered into the interior space in a controlled fashion. Hot water is supplied via a buffer tank and the freshwater module for safe drinking water. Solar systems equipped with GASOKOL high-performance solar collectors achieve maximum collector field yield. This leads to maximum efficiency and makes it possible to avoid using fossil fuels.



Outstanding solar system by GASOKOL

Winner of the ENERGY GLOBE Award Salzburg, in the ‘Earth’ category


The Hallwang Cultural and Community Centre is a PlusEnrgyHouse and an architectural jewel all at once. This is ensured by 138 m2 of thermal solar collectors, meeting the entirety of the building's annual heating and hot water needs, which total 40,000 kWh plus 20,000 kWh of excess energy fed into a district heating network. The high-performance GASOKOL gigaSol OR solar collector was specially developed for 100% solar-heated buildings. The energy solution was implemented in conjunction with Harald Kuster, FIN Future Is Now and GASOKOL.
The building is supplied with heat exclusively using solar energy. This means that no CO2 is emitted for space heating and hot water heating, and that there are no energy costs. The excess energy generated by the Hallwang Cultural and Community Centre is fed to the neighbouring tourist agency. The model project was submitted by the Municipality of Hallwang and was declared the winner of the Energy Globe Award Salzburg, in the ‘Earth’ category. Within the greater cross-border area of Salzburg/Upper Austria/Bavaria, with 343,000 inhabitants, this pioneering building is also used as a convention centre for seminars on the topic of energy.

Energy Globe Award

The Energy Globe Award is conferred annually in recognition of environmental innovation. With 161 participating countries and over 1000 annual project submissions, the Energy Globe is the world's largest platform for sustainability and the world's most important environmental prize. It is bestowed each year on projects with a focus on energy efficiency, renewable energies and resource conservation.
The winning Energy Globe projects serve as model projects in the following five categories: Earth, Fire, Water, Air and Youth. Jury chairwoman Maneka Gandhi: ‘This award has marked milestones on the way to a sustainable future for over a decade now!’



The high-performance collector for solar building structure activation
GASOKOL gigaSol OR

The high-performance gigaSol OR solar collector with its highly selective solid copper absorber was specially developed for buildings with solar building structure activation, making it an on-roof and open area solar collector that can be used for an even wider application spectrum. Whether used in a pitched-roof, flat-roof or freestanding installation, the gigaSol OR can be used universally and can be scaled as needed. Collector-optimised fastening systems made of aluminium and stainless steel round out the wide range of installation options. OR, incidentally, stands for on-roof. Gross areas from 2.23 m2 to 11.07 m2 are offered for each gigaSol OR collector. The expansion-joint free absorber geometry with its plant-optimised connector positions enables special connection of up to 40 m2. A thermally optimised ventilation system further increases efficiency and improves the operating conditions. Rapid installation times and rapid return on investment in conjunction with durable design top the wish list of every plant operator. From single-family homes to industrial facilities, the gigaSol OR can rise to applications of any size.

In order to stand out amidst the global competition, European solar collector manufacturers have to continue to focus on ongoing research and development, quality of materials and proven technology to produce products offering decades of stable efficiency and constant solar energy yield.



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