Green Therma designs, drills, completes and installs the deep earth heating solution, Heat4Ever, as a fully integrated project that can connect to the utility company’s district heating grid or to a private enterprise heating system.

It can connect to:

District heating


Manufacturing facilities



Leisure centres

Geological Requirements

The horizontal closed loop system has less geological requirements, as there is no direct fluid interaction with the geological formation. The two main geological requirements for a successful well are having the right temperature in the formation and the right geological setting that can be drilled successfully.

In Denmark, GEUS (Denmark and Greenland Geological Survey) and Aarhus University have mapped the temperature distribution at depth in detail based on all available well data. The distribution is widely known and reasonably consistent. Green Therma will utilize this data when selecting the right drilling sites, so we can ensure that the drilling is executed in a safe and cost-effective manner, and that the right temperature for the system is reached.

Many areas in Denmark are geologically suitable for Heat4Ever systems, with known geology and temperature distribution of the different target geological formations.

For other countries Green Therma will engage with the local authorities and geological surveys to obtain relevant subsurface information to optimize the location of wells.

Utility Companies

In Denmark, district heating covers more than 66% of households with the goal to reach 75% by 2030.

The overall share of renewable fuel for district heating in Denmark is over 50% and consists mostly of burning biomass and waste. The over reliance on biomass energy has led to some sustainability concerns including CO2 emissions, impact and change of land use, and negative effects on biodiversity. Utility companies have also become increasingly focused on reducing dependency on natural gas by diversifying energy sources.

Green Therma Heat4Ever solution is superior to existing fuel sources for heat generation when it comes to costs, durability, stability, environmental emissions and it addresses the zero-carbon challenge effectively.

Local District Heating Solution

A “zero emission” solution, where 10 to 12 wells are drilled in a star formation to a depth of 3.5 km each with a 4-5 km horizontal section can provide enough heating to 25,000 people.

Such a 10 well solution can provide 20 to 25 MW of energy to a district heating system replacing any other types of fuel. This energy is completely green with zero CO2 emissions.

Around 12 to 15 thousand households can be supplied with reliable heat all year round.

Commercial Enterprises

Larger commercial enterprises such as horticulture, manufacturing facilities, breweries, or recreational centers have heat requirements for their facilities or for their production. The heating that is needed is often at a lower temperature than for district heating. This can be met by drilling shallower and less expensive wells. In some cases, even a single well may meet the entire heating requirement.

Full Suite Solution


Green Therma is a technology and service company that delivers world class executed deep earth heating projects to utility companies and private enterprises providing low risk, reliable and sustainable energy.

Green Therma plans, drills and completes horizontal deep earth heating wells with our patented Dual Vacuum pipe technology.
We drill deep horizontal closed loop geothermal wells at a 2-4 km depth with a 2-8 km horizontal section to generate 2 to 4 MW of energy. It can be a single well or a group of wells depending on the energy needed. Each well will be completed with the Dual Vacuum pipe technology (DualVac) and connected it to the local district heating network.

In cooperation with our strategic alliance partner, Nabors, the world’s largest onshore drilling rig contractor and our extensive project management experience from the offshore energy industry, Green Therma delivers a fully integrated Heat4Ever project to utility companies and private enterprises.

2-8 km horizontal section

Single or group of wells

Completed with DualVac

2 to 4 MW energy from each well

Significant Drilling Cost Savings

By reducing the requirement for providing hot water from 2 to 1 well there is a significant drilling cost saving.

The well with its steel tubing is not exposed to oxygen or outside fluids and will therefore not corrode providing a very durable solution.

With the Dual Vacuum pipe technology (DualVac) very limited maintenance is required of the whole system as there is no interaction with the formation water, which can cause various problems in relation to the whole system. Furthermore, all facilities are located on the surface for easy service and replacement.

Get in Touch!

Get in touch!

Feel free to ask us about our solution, technology or any other questions you may have

Want to meet us?

We are presenting our solution at industry events and conferences. Feel free to reach out, if you would like to meet up.