District heating

Cadaujac

This solar district heating system of 941 m2 in Cadaujac is an innovative and eco-friendly project, first of this type in France, develop by our customer AbSolar. The solar production is linked to a geothermal seasonal storage which lead this new neighbourhood to received 100% of renewable heat for their need in heating and hot water.

Savosolar has been responsible of the main part of the solar plant as part of an EPC contract, including the design and then the supply and installation of the solar field, the piping and the solar station with its automation system, as a turnkey solution. The 510 MWh of annual solar production allow to avoid around 100 tons of CO2 emission for such a heating need. With this project, Savosolar maintain is leading position on the French market in the supply of turnkey solar thermal plant for district heating.

This disruptive technology develops and handle by AbSolar is a forerunner project showing the possibility to reduce significantly our carbon footprint for the daily needs of heat and should help us to fight climate changes, while ensuring a mainly fixed cost of energy over 20 years for the inhabitants of this kind of residential district.

Location

France

Construction status

Finished

Installation year

2021

Solution type

District heating

Number of collectors

59

Collector Area

941 m2
, gross

Collector Type

Savo 15 SG M

Power

720 kW

Energy production

510
MWh/a

Suur-Savon Sähkö

Savosolar has been selected as general contractor to build the largest solar thermal system in Finland to date, on behalf of Suur-Savon Sähkö Oy for its district heating network in Puumala, which supplies households with healthy heating. In this hybrid installation the solar thermal system is producing both, high-temperature heat to district heating supply pipe and also low-temperature heat to improve heat pump plant COP.

Jelling Varmeværk

Jelling Varmeværk is a Danish district heating plant in the historical village of Jelling, which is the former home of the Viking Chief Harald Bluetooth. Apart from the 20,125 m² collector field, Jelling Varmeværk produces its energy from a 1 MW wood chip boiler, a 1.5 MW absorption heat pump and 2 gas CHP engines with a total capacity of 8 MW heat and 6 MW electricity.

The first solar system was commissioned in summer 2016 and during its first week of operation, the collector field set a new Danish record by producing nearly 5 kWh/m² in a day.

The collector field in Jelling has double stanchions which allows for two collector rows to connect to one and the same pipe and thereby save costs and thermal losses. The annual solar thermal production is about 11,200 MWh, which covers over 25% of the town’s energy need for heating.

In 2018, Jelling Varmeværk placed a second order with Savosolar for the 4,836 m² extension of the successfully running existing collector field. The extension will be installed in first half of 2019 and it will further grow the fraction of district heating produced with solar energy.

“We chose Savosolar as our collector supplier due to their high efficiency in combination with their innovative solutions. They enable us to have an environmentally friendly, stable and low price for heating over the next 20 years. Collectors have integrated hose connections which means that they disturb the landscape as little as possible in an historic village of Jelling. The collectors can also follow the curvature of the landscape which means that we didn’t have to level out the ground of the field.”

Bjarne Nielsen
Plant Manager, Jelling Varmeværk district heating plant

Lolland Forsyning

Lolland forsyning’s district heating plant in Søllested is located on the island of Lolland and was the first installation, where Savosolar’s double glazed collectors were used. The double glazing reduces heat losses through the glass side of collector and offers a higher efficiency, especially at higher operation temperature levels and during the darker months of the year. Søllested district heating plant has ca. 500 customers and also uses a 5 MW straw boiler and an oil burner to produce its heat.

The collector field in Søllested has a so-called hybrid field, with both single and double glazed collectors. The single glazed collectors are in the cold end of the collector rows and increase the low temperature as rapidly as possible, while the double glazed collectors are located in the warm side of the collector rows where it is more important to reduce the heat losses.

In Søllested, Savosolar was faced with a special challenge since the customer’s land has a sewerage pipe running through it. Since the owner of the sewer pipe needs to be able to access it in case of maintenance, Savosolar supplied a collector field which both optimised the use of the available land, while still providing access to the sewer pipe