Finnish geothermal heating project continues despite challenges

Espoo - Finland (Soruce: Flickr CC - By: Alexander Savin)
Alexander Richter 7 Sep 2017

Drilling continues at unique geothermal heating pilot project in Espoo, Otaniemi in Finland, but drilling cost might be challenging for additional projects going forward.

The unique geothermal heating project in Espoo, Otaniemi in Finland has been a rather interesting project from the start. Drilling to such deep depths for a heating project only is rather unique. ThinkGeoEnergy has reported on the project before.

The project has though run into some challenges and has become more expensive than planned.

“Drilling costs represent well over half of the entire plant’s investment and drilling costs are now significantly higher,” says Jari Suominen, President of St1 Deep Heat Oy in an article in local publiction Yle.

According to the original plan, the plant is planned to produce up to 10 percent of the district heating for Espoo. The project was to be a catalysator for further development in the wider area, where most of the heating today is still produced by combusting natural gas and coal. But with the current energy prices and the high cost of drilling technology, a duplication of the pilot plant might not be commercially viable.

It is always difficult to develop such an innovative new project and quite costly. But despite that the wells drilled so far with hammer technology made it to a depth of 4,500 met cost expectations, they did not drill to the target depth of 7,000 meters as planned. So it is impossible to estimate the final cost until the project is done.

The hiccup is due to the drilling technology using water hammer technology. Drilling was stopped in February at a depth of 4,500 meters. At that point, the developer St1 announced that it will explore other technology to continue to drill down to the targeted depth.

Since July this year, drilling has continued with more traditional rotary drilling technology. In practice, this means drilling is both slower and more expensive.

“This task may be more challenging than we expected, although we knew that there are many risks involved,” says Suominen.

Now drilling has reached a depth of 5,000 meters and is expected to continue to drill deeper. Despite the challenges, this does not necessarily have a radical impact on the plant’s production.

St1 continues to drill the first hole. By the end of the year, experiments should be conducted to determine the permeability and warming of the water in the hole in the bedrock. At the beginning of 2018, a second hole is to be drilled, whereby heated water is fed to the ground to warm the Espoo houses.

“There is no need to throw the towel here”, says CEO Suominen.

According to Suominen, more economical and quicker aquaculture is not yet completely forgotten.

“Yes, we are tracking the technological development of the industry and we are wondering if it should be involved in the development of drilling technology.”

Source: Yle Uutiset