Sonnen Speicher Süd
Automated translation. English version for convenience only.
Sonnen Speicher Süd harnesses the natural power of the sun to replace fossil, climate-damaging energy. Existing regional infrastructure is used efficiently to store clean solar energy. In the future, this will cover around 30% of Graz's district heating demand with environmentally friendly energy.
A project by Styrian companies
For thermal storage, solar energy and heat pumps, Wärmespeicher Weitendorf GmbH together with
Ecker-Eckhofen
Energie und Rohstoffe
in close collaboration with
For biomass and the heat transmission pipeline, BWE Energieservice GmbH together with
in close collaboration with
Solar collectors with a gross collector area of 28 hectares heat the water to around 90 °C and then transfer it to the thermal storage facility.
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The quarry in Weitendorf is ideally suited for the conversion into a thermal storage facility with a volume of around 1.5 million m³. A thermally insulated floating cover allows the storage facility to retain the energy until spring and to cover the heating demand in an environmentally friendly way.
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The water at around 90 °C is heated as needed to up to 120 °C by the biomass heating plant (around 49.5 MW firing rate). This allows the water to be fed into the district heating network.
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The high-temperature heat pumps (60 MWth), which are preferably operated during periods of surplus electricity, use the storage facility as a heat source and ensure optimal temperature stratification. This enables highly efficient operation of the storage facility and the solar collectors.
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The generated and stored thermal energy is fed into the district heating network via a pipeline of around 4 km and covers around 30% of Graz's total district heating demand.
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Solar collectors with a gross collector area of 28 hectares heat the water to around 90 °C and then transfer it to the thermal storage facility.
The quarry in Weitendorf is ideally suited for the conversion into a thermal storage facility with a volume of around 1.5 million m³. A thermally insulated floating cover allows the storage facility to retain the energy until spring and to cover the heating demand in an environmentally friendly way.
The water at around 90 °C is heated as needed to up to 120 °C by the biomass heating plant (around 49.5 MW firing rate). This allows the water to be fed into the district heating network.
The high-temperature heat pumps (60 MWth), which are preferably operated during periods of surplus electricity, use the storage facility as a heat source and ensure optimal temperature stratification. This enables highly efficient operation of the storage facility and the solar collectors.
The generated and stored thermal energy is fed into the district heating network via a pipeline of around 4 km and covers around 30% of Graz's total district heating demand.
"By 2040, the City of Graz's climate target is to provide 100 percent of heating from renewable energy."
- Graz Climate Targets
"Graz's heat supply still contains a great deal of natural gas and oil. Shifting these heat shares toward decarbonized heat will be one of the major challenges of the coming years."
- Werner Prutsch, Environmental Office of the City of Graz
"I was very impressed by the size of the facility. Larger storage facilities have less surface area in relation to their volume. This means they are more efficient than smaller storage facilities."
- Morten Vang Bobach, thermal storage expert
"The facility with the world's largest thermal storage system can cover 30% of Graz's total district heating."
- Heimo Ecker-Eckhofen, initiator
In the future, Sonnen Speicher Süd will supply over 30% of Graz's district heating with environmentally friendly, clean energy. This will save approximately 100,000 tonnes of CO2 per year.
Mag. Heimo Ecker-Eckhofen
PROJECT INITIATOR
Heimo Ecker-Eckhofen has already realized several hydropower plants and a floating photovoltaic system and specializes in renewable energy. The thermal storage facility is intended to mark the beginning of a new, more sustainable future.
DI Georg Schweighofer
Georg Schweighofer has successfully managed major projects in the energy sector for more than 20 years, both nationally and internationally, and has extensive expertise in planning and construction execution.
Dr. Gilbert Frizberg
As owner of Hereschwerke and former chairman of the supervisory board of Verbund AG, Gilbert Frizberg has outstanding expertise in energy generation, distribution and sales. He also has extensive connections within the Austrian and European energy industry.
Mag. Pirmin Proier
With a background in physics and product management, Pirmin Proier is responsible for operational project management at Sonnen Speicher Süd, from funding acquisition and tenders through to optimization of the plant concept.
DI Dr.techn. Michael Reisenbichler-Sommerhofer
Through his doctorate at Graz University of Technology and many years of experience leading and contributing to national and international research and development projects, Michael Reisenbichler-Sommerhofer has in-depth expertise in thermal energy systems, especially in the field of large-scale underground thermal storage facilities.
Mag. Jakob Edler
The bioenergie Gruppe has many years of experience in the construction and operation of biomass heating plants and district heating pipelines. In the Sonnen Speicher Süd project, the bioenergie Gruppe will build the biomass heating plant to reheat the solar heat and the district heating pipeline, including its connection to Energie Steiermark's network.
ENSO
As a pioneer in developing and implementing projects focused on sustainability and environmental protection, ENSO has made a name for itself in the industry.
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Kommunalkredit Public Consulting
Public Consulting, a leading public-sector advisor, has more than two decades of experience supporting governments and public institutions. With a deep understanding of public administration and funding policy, Public Consulting offers tailored solutions for complex public-sector challenges.
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