In just seven months Arcon-Sunmark has accomplished the construction of the record-breaking large-scale solar heating system at the city of Silkeborg, Denmark. 20% of the annual heating demand will from now on be produced via renewable energy coming from the sun above us and harvested by a collector field of 156.694 m2.

445 times in the past seven months a truck has been loaded with solar collectors at the Arcon-Sunmark headquarters in Denmark, in order to make the an hour and a half drive to the construction site of the world’s largest solar heating system. 12.436 collectors each measuring 12,6 m2 giving a total of 156.694 m2.

On a sunny summer day 2,7 million litres of water will pass through the system every hour. The system is connected to the main heating facility by 1,2 kilometres of piping. With an annual yield of 80.000 MWh the system will cover the heating requirement of 4.400 average households or 20% of the annual demand. “One fifth of Silkeborg’s annual heating consumption from now on will be covered by solar heating, and we are proud to be part of the project together with Silkeborg Forsyning. It is a proof of how swiftly a transition to renewable energy can be executed and that the process does not have to be long and time-consuming,” says Søren Elisiussen, CEO, Arcon-Sunmark.

The contract between Silkeborg Forsyning and Arcon-Sunmark was signed in February 2016. In May the construction began, and at the end of December the installation was put into operation.

Experience – key to success
Despite the fact that the solar heating system at Silkeborg is more than twice the size of the largest one until now – which is the system in Vojens, Denmark – the project has in no way been experimental. In fact, Arcon- Sunmark has constructed more large-scale solar heating systems than any other company in the world, and therefore has had the required skills and expertise to achieve the construction in just seven months. “We have acquired an extensive knowledge and experience over the years in designing and constructing very big solar heating systems both in Denmark and internationally. However, due to the enormous size and the very tight time schedule the system at Silkeborg is one of a kind, and therefore I would like to thank everybody who has been involved and contributed to the development of the system,” says Søren Elisiussen, CEO, Arcon-Sunmark.

Facts about the solar heating solution:
 Number of collectors: 12.436
 Collector area: 156.694 m2 (the largest solar collector field in the world)
 Location: Silkeborg, Denmark
 Annual production: 80.000 MWh
 Peak effect: 110 MW
 Annual demand covered: 20% (the remaining 80% is covered by gas and surplus electricity)
 Number of consumers: 90.000
 In operation: End of 2016
 Life span: 25 years minimum

About Arcon-Sunmark A/S:
Arcon-Sunmark is a merger between two of the world’s leading companies within large-scale solar heating – ARCON Solar and Sunmark. ARCON Solar was established in 1974 in Skørping, Denmark and was a pioneer in the large-scale solar thermal industry, with a special focus on solutions for district heating. ARCON Solar has installed the largest large-scale solar thermal systems in Europe. Based on more than 25 years of experience and know-how, Sunmark was established in 2008 on the isle of Ærø, Denmark. Sunmark established highly specialized production facilities both in Denmark and in Asia, and installed the world’s largest solar plant for the mining industry – in Chile. In 2015 the two companies joined forces to establish the world’s leading company in this line of business. Arcon-Sunmark has installed solar heating solutions for district heating plants, breweries, mines and the greenhouse industry and is behind more than 80% of the largest plants in Europe. Arcon-Sunmark is owned by VKR Holding. In total, VKR Holding’s companies employ some 13.500 people in more than 40 countries. VKR Holding owns companies, which bring daylight, fresh air and a better environment into people’s everyday lives. We always choose the most solid and reliable partners. Like Energia Llaima in Chile.

Installations, examples:
Since 1988 Arcon-Sunmark has built more than 100 large-scale solar heating systems (>1.000 m2) altogether totalling more than 1 million m2. The oldest installations have been in operation for 28 years. Here 2 further examples of Arcon-Sunmark projects of more recent date:

For district heating: In the Danish city of Vojens, Arcon-Sunmark was chosen as the supplier to install a large-scale solar heating solution. In 2012 a 17.500 m² plant including a 3.000 m³ steel tank became reality. The results were so impressive that an extra 52.500 m² were added only a couple of years later, in 2014/2015. By now, the collaboration has led to a 70.000 m² installation, and a 200.000 m³ thermal pit storage for storing excess solar heat for periods of time where the sun delivers less energy. The storage is excavated in an old gravel pit. The effect is a calculated annual production of 28.000 MWh, which covers app. 45% of the total heat demand.

For industrial process heating: For Gabriela Mistral Division of Codelco, which is a Chilean copper mine, Arcon-Sunmark installed the world’s largest solar heating solution for industrial process heat. Mining processes are energy intensive in their operation. One of them is electro winning (EW), where it is required to heat water or electrolyte solutions in order to optimize the process and thus to obtain high quality cathodes. Before the 43.920 m2 solution was put into service, an annual flow of 250 trucks transported 8.000 m³ of fuel to be used in the EW process, for the production of 120.000 tons of copper per annum. Today, the solar plant covers 80% of the annual energy demand for the heating of water, thus avoiding the emission of 15.000 tons of CO2 per year into the environment.