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COWI TO DESIGN 100 MW ICELAND GEOTHERMAL PLANT

Cowi to Spearhead 100MW Geothermal Power Plant Expansion in Iceland: A Leap Toward Renewable Innovation

By: Robert Buluma

In a major stride toward sustainable energy development, Cowi, a leading engineering firm, has secured the design contract for the expansion of the Hellisheidi Geothermal Power Plant in Iceland. This ambitious project, driven by ON Power, will see the plant's capacity increase by 100MW, further solidifying Iceland's commitment to harnessing its geothermal potential. 

The Hellisheidi plant, located just 18km from Reykjavik, serves as a cornerstone for Iceland's energy landscape, providing both electricity and hot water for domestic heating. With the ongoing expansion, the plant’s heating output will rise from 200MW to 300MW, ensuring more homes and businesses in Reykjavik benefit from geothermal energy.

A Legacy of Excellence

Cowi's involvement in the Hellisheidi project dates back to its early phases, when the firm, formerly known as Mannvit in Iceland, was instrumental in the plant's initial design and construction. Having been selected for this new phase from a pool of three bidders, Cowi will be responsible for overseeing the engineering design, preparing tender documents, and providing support through to the project's commissioning in 2026.

This new expansion is poised to enhance Hellisheidi’s existing output of 303MW of electricity and 200MW of thermal energy. The plant is not only Iceland's largest geothermal combined heat and power (CHP) facility but also ranks as the fourth-largest geothermal power plant in the world.

The Science Behind Flash Steam CHP

The Hellisheidi plant operates using flash steam technology, a complex but highly efficient process for generating both electricity and heat. Geothermal fluid is extracted from production wells and piped to a central separation station. Here, steam is separated from water under high pressure and sent to turbines, where it generates electricity. The water, in turn, is flashed at lower pressures to produce additional steam, which powers more turbines. The remaining water is used in heat exchangers to produce the hot water that is piped to Reykjavik for district heating.

Once the water has been used, it is pumped back into the earth via re-injection wells, making the entire process as sustainable as possible.

Expanding Iceland's Geothermal Horizons

The expansion project is not just a technical upgrade—it represents Iceland’s commitment to maximizing its geothermal potential. Hellisheidi is located in the Hengill geothermal area, an active volcanic ridge that spans 112 square kilometers. The geothermal activity in this region is linked to three volcanic systems, making it one of the largest geothermal areas in Iceland.

Base Load Capital, Icelandic affiliated company just recently minted Big in Geothermal and Its awesome that Geothermal is not just the Future but an eternity

As the world continues to search for sustainable and clean energy solutions, projects like Hellisheidi are vital examples of how countries can leverage their natural resources to reduce carbon footprints.  Cowi'scontinued involvement in this project underscores its expertise in geothermal energy, a field that is rapidly gaining attention worldwide.

With the Hellisheidi plant expansion, Iceland is taking a bold step forward in renewable energy. As Cowi leads the engineering design, the project sets a benchmark for future geothermal developments, not only in Iceland but globally. The world will be watching as this pioneering project unfolds, proving that geothermal energy is key to a greener future.

Get a glimpse of the facts on this unique power plant.

By 2026, the expanded Hellisheidi plant will stand as a testament to Iceland’s leadership in geothermal energy and the engineering prowess of Cowi.

Researched and Written by Alphaxioms

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This recently published Tender in Geothermal is intriguingly captivating


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