Green Therma has selected Helmerich & Payne as drilling contractor for its Heat4Ever geothermal demonstration project in Aalborg, advancing plans to drill what is expected to become Denmark’s deepest and longest geothermal well.
The closed-loop project will demonstrate a single-well architecture intended to produce renewable heat without relying on a conventional naturally productive geothermal reservoir. Drilling is targeted to begin in January 2027.
H&P Selected for 7km Well Architecture
The project calls for a well reaching approximately 4km vertically, followed by around 3km of horizontal drilling.
H&P will deploy its Rig T203 together with drilling personnel and operational expertise.
“Selecting the drilling rig partner for Aalborg turns that ambition into reality. We’re delighted to have H&P alongside us as we prepare to drill…” said Jørgen Peter Rasmussen, CEO and Founder of Green Therma.
Closed Loop Avoids Reservoir Dependence
Heat4Ever differs from conventional geothermal doublets.
Water circulates inside the closed well rather than being produced from and reinjected into a natural geothermal aquifer. Underground rock transfers heat into the circulating fluid, which can then supply district-heating infrastructure.
This architecture could widen geothermal’s usable geography because a project would depend less on locating a productive hot-water reservoir.
DKK84m Support Helps Fund Demonstration
The Aalborg development has been structured with Aalborg Forsyning as heat offtaker.
It has also received DKK84 million in funding support from Denmark’s Energy Technology Development and Demonstration Program, strengthening the project’s pathway from technology development into full-scale field testing.
Green Therma previously partnered with SLB on development of the Heat4Ever concept, while later industry collaborations have focused on drilling and well-completion requirements.
Drilling Contract Moves Technology Toward Reality
The selection of H&P is important because it moves the project beyond engineering design into physical execution planning.
Closed-loop geothermal has attracted significant industry interest because it could reduce exploration and reservoir-performance risks that affect conventional developments.
The Aalborg project will test whether that concept can operate at commercial-scale depths while delivering usable heat into an existing district-heating system.
If the demonstration succeeds, Heat4Ever could provide another route for expanding deep geothermal heating in locations without naturally productive geothermal reservoirs, making the project an important technology test for Europe’s renewable-heat sector.
