Solar Heat

District Heating Holzgerlingen, Housing District Hülben

In December 2005, a novel solar thermal system, commenced operation in a housing district of Holzgerlingen; it included a wood pellet stove for warm water and heating support. This CO2-neutral heating system of the housing district Hülben supplies 44 single family homes, 36 apartment units and one kindergarten. The insulation standard of the buildings lies considerably below the Energy Saving Regulations (EnEV).

Apart from the solar thermal system with a collector surface of 248.8 m², there is a wood pellet stove providing additional 540 kW. Three buffer storage tanks are integrated into the heating system to store the heat. 

Since solar power is used for warm water heating and space heating, fuel can be saved thus reducing greenhouse gas emissions as well as costs. 

Immotherm Stuttgart is the operator of this local heating system with integral solar support.

Holzgerlingen was chosen for Solarthermie2000plus for several reasons:

•  The new roof area is well suited for mounting collectors.
• The concept was carefully planned and well-thought through.
• A good demonstration effect.
• The insulation of the buildings is clearly below the standard requirement of the Energy Saving Regulations.
• The heating costs were expected to remain below 0.15 €/kWh. 

Project Partners