World’s largest pit thermal storage in Vojens
In Vojens, Denmark, a 200,000 m³ pit thermal storage basin stores surplus solar heat from a 70,000 m² collector field. Using Solmax geosynthetics, the system reduces CO₂ emissions by 6,000 tons annually.

Attica’s 66 municipalities and four million inhabitants depend on a single landfill – Fili. First established in 2003, the Fili landfill was expanded in 2006 and continues to grow.
Because the landfill is growing rapidly, it is running out of space. Further expansions required highly technical solutions, and geosynthetics play a vital role in the safe design and containment of seepage from the waste.
In 2021, construction commenced on a new landfill bordering the existing one. With little available ground to expand on, an artificial basin was built on the border of the existing landfill. The basin had a capacity for 4.1 million m³ (145 million ft³) of garbage. This landfill will be used for several decades to come.
Tsakas Construction chose Solmax to supply the geosynthetics for the landfill's expansion. “The Fili Landfill has reached capacity and expansion is critical,” explains Elektra Tsaka, CEO at Tsakas Construction. “With proven geosynthetic solutions used in some of the biggest landfills in the world – as well as the ability to consistently deliver high-quality products on time, Solmax was our first choice for this project.”
The proposed Solmax solution met the client’s key requirements –it offered the right quality and price and provided an end-to-end solution.
To line and cover the landfill, the following materials were supplied:
60,000 m² (646,000 ft²) of FABRINET® drainage geocomposite
51,000 m² (549,000 ft²) of double-sided textured GSE Frictionflex geomembrane from Solmax’s plant in Germany
95,000 m² (1 million ft²) of GSE® Frictionflex from Solmax’s plant in Egypt.
By combining delivery from the two plants, Tsakas was able to guarantee the timeous delivery of large amounts of material for the project.
The materials met with stringent specifications to ensure they perform well and provide safe containment of waste.
GSE Frictionflex is a double-sided textured high-density polyethylene (HDPE) geomembrane. It is used in applications that require increased frictional resistance, excellent chemical resistance and endurance properties.

FILI LANDFILL EXTENSION, GREECE

FILI LANDFILL EXTENSION, GREECE

FILI LANDFILL EXTENSION, GREECE
World’s largest pit thermal storage in Vojens
In Vojens, Denmark, a 200,000 m³ pit thermal storage basin stores surplus solar heat from a 70,000 m² collector field. Using Solmax geosynthetics, the system reduces CO₂ emissions by 6,000 tons annually.
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