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Best in class pipes

Geothermal energy is a readily available, natural, renewable and local energy source. It is predominantly used for electricity and heating. The sheer mass and relative proximity, ranging from a few metres to a few thousand metres deep, make geothermal one of the leading energy sources for the coming decades.

Geothermal energy piping PB plastic
Geothermal energy piping system

Once extracted from the energy source, low-temperature heat can be distributed directly. With higher temperatures, steam and electricity are generated first before the residual heat is distributed through a district heating network.
In all geothermal projects, it is important to choose the right material for the pipes. The immediate environment and water can be hostile, due to its mineral and gas content. PB1 pipes are known for their excellent chemical resistant and have an impressive track record in geothermal projects.

Deep geothermal

Deep geothermal energy generally involves temperatures in excess of 100 ˚C and is used for electricity generation, before providing heat for commercial, industrial, horticultural and residential buildings. The geothermal well is referred to as the vertical part, whereas the district heating network is known as the horizontal part.

Shallow geothermal

Shallow geothermal energy is obviously less deep, is cheaper to extract, can be developed for smaller scale projects and requires a smaller surface area. It is ideal for providing heat directly to district heating networks for residential areas, hospitals, universities or industrial estates.

More about heating networks

Direct geothermal

In certain geographical areas, the hot water is so close to the surface that it can be fed directly into the district heating network. While investments are minimal, the feasibility depends on the local availability of a heat source.
In these projects, the composition of the geothermal water determines which pipe should be used. Please contact us to find the right pipe for your situation.

Passive geothermal

An enormous thermal mass at a stable temperature can be found just below the surface. This is ideal for ground source heat pumps. Underground heat collectors absorb subsurface heat, which is then extracted by a heat pump to increase the temperature for underfloor heating or other low-temperature applications. These projects typically power a single home or office building, or feed into a small local district heating network.
Extremely flexible pipes or preselected pipe installation kits allow for quick and reliable installation.

Pipe systems for geothermal energy

The construction of sustainable networks for geothermal energy requires a pipe system that is up to the task of making geothermal energy directly available to households and businesses.
The pre-insulated Flexalen pipe system offers a wide range of lightweight flexible prefabricated products that are ideal for geothermal applications. For example, the polymeric Flexalen PB is abrasion proof and comes with the best chemical resistant service pipe in its class. This allows the project to benefit from short installation times and results in an extremely reliable network for (geothermal) water transportation.

Our productlines for Geothermal energy

Flexalen 600

Flexalen 600 flexible pre-insulated pipes offer a single solution for district heating, cooling networks and domestic water supply and are ideal for...

Flexalen PU

Flexalen PU pre-insulated pipes are specially designed for medium to large heating networks where flexibility is required in combination with the highest...


The universal, robust and flexible Protectube insulation channel is suitable for various combinations of pipes, tubes and cables. Protectube insulates and protects....

Flexalen prefabrications

Joints, branches and connections are the most critical parts of networks for heating, cooling or drinking water. Our prefabricated Flexalen network elements...

Flexalen system accessories

We offer all the necessary components/parts to install our integrated pre-insulated Flexalen piping system quickly and properly. We offer a complete system,...

Flexalen tools

The performance of piping systems for heating, cooling or drinking water is heavily dependent on proper installation. The use of proper tools...

Jasper van de Ven Sales manager Piping Solutions
Jasper van de Ven

Int. Sales Manager pre-insulated pipings

Ask our expert

Jasper van de Ven is happy to help you find the best solution for your specific application. Ask your question and get advice within 3 business days!

Why Thermaflex?

We develop and supply high-quality technical solutions for insulation, protection, shock resistance and soundproofing.

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Pre-insulated pipes

Flexalen 600 flexible pre-insulated pipes offer a single solution for district heating, cooling networks and domestic water supply and are ideal for geothermal water distribution.

Flexalen600 heating cooling
Flexalen600 pre insulated pipe for heating cooling networks