Innargi

A step towards energy independence: Geothermal district heating in Hillerød.   We’re happy to share that we have signed an agreement with Hillerød Forsyning to explore the potential of geothermal district heating in Hillerød. This collaboration supports their goal to phase out natural gas, reduce biomass consumption, and expand green, cost-effective heating to more citizens.   As Denmark transitions away from natural gas, this project reinforces energy security and industrial resilience. One of geothermal’s greatest strengths is its reliability—day and night, in any weather—providing a stable, independent energy source. By integrating geothermal into district heating, we are paving the way for a long-term, resilient solution that isn’t affected by market fluctuations or external conditions. As Tue Tortzen, Chairman of the Board in Hillerød, says: “Utilising geothermal energy for district heating is an obviously good idea and an ambition that the board has worked hard to make a reality. The collaboration with Innargi enables us to secure CO2-free heat that neither Trump nor Putin can shut down.”   We are excited to get to work! 💪   Find link to the full press release in comments below.

Topping-Out Ceremony: A True Celebration with All Contributors in Aarhus! Bread, sausages, and chocolate flowed abundantly last Thursday as we gathered to celebrate the completion of the structure for our new heating facility in Skejby, Aarhus. It was the perfect occasion to celebrate with our partners and the hardworking team who have made this possible over the past few months. According to an old Danish tradition, the owner must smash a beer bottle at the topping-out ceremony and say: "May the building last as many years as the glass shatters." At Innargi, we don't rely on superstitions. We trust our skilled engineers, building constructors, and team to build a heating facility that will last at least 30 years. These are the people we can count on. And now, the structure is complete. 'Well, the outer walls and rood, that is. Next step is to cover the building with green facade panels to make it fit into the park it is located in. All equipment will be installed and connected during the coming months and at the end of this summer we expect to switch on the system to supply Kredsløb district heating network. We are incredibly proud and excited to turn on the tap to produce local, stable, and more sustainable heating to citizens of Aarhus! 💧

We’ve got a date! 📆   We welcome the European Commission’s announcement to step up their efforts with a commitment to publish an EU Heating and Cooling strategy in Q1 2026. This was announced as part of the Clean Industrial Deal and the Affordable Energy Action Plan yesterday.   Geothermal energy is a local, renewable, reliable, affordable and community-friendly energy source, making it a key enabler in decarbonising our district heating grid across Europe. By doing so, we can achieve more predictable prices, a secure heat supply and enhance value-creation within Europe.   To accelerate the deployment of large-scale projects, such as the one we are currently undertaking in Aarhus, it is crucial that the European Commission fully delivers on the announced measures by:   🔸 Ensuring investor certainty by proposing climate and renewable targets for 2040. 🔸 Presenting a geothermal energy action plan, as called for by EU Member States and the European Parliament. 🔸 Including geothermal and district heating in the proposals to accelerate permitting for renewables.   We are excited to continue driving the transition to a greener, more affordable, and secure energy future and to see the European Commission's commitment come to life! 

Not all subsurface formations are geothermal gold 🥇 ... but fortunately, we are quite lucky with the subsurface conditions in many countries in Europe. Before starting a project, one of the first steps we take at Innargi is analysing the subsurface to see if the conditions are suitable for geothermal energy. Not all underground formations can support district heating production, so what makes a good geothermal reservoir? 🔸Water-filled and warm: The underground formation must be porous and deep, so that it can contain water that’s warm enough to produce heat . 🔸Right properties for extraction: The reservoir must be thick and permeable enough to allow water to be pumped in large quantities. Our colleague, Emil Stürup-Toft, is a geoscientist and always has an eye out for the optimal trade-off when searching for good geothermal reservoirs: “Analysing the subsurface is about finding the right balance. Geothermal reservoirs need the right combination of temperature and flow to transfer energy efficiently to district heating systems. As we go deeper, the temperature rises, making the water hotter and thereby better for heat production. However, depth also increases pressure, which typically compacts the rock and reduces water flow, making extraction harder.” If Emil is not able to find perfect local subsurface conditions, we are lucky to have other tools that we can use. That’s where heat pumps may come in handy: if the geothermal water isn’t hot enough for the district heating system, the heat pump raises the temperature to the necessary level, ensuring a steady and reliable supply for district heating, even if the reservoir itself can’t provide the required temperature. The subsurface potential is present in many countries in Europe and by utilizing the heat beneath our feet, we are able to produce local, stable and greener heating for millions of households.

Geothermal isn’t just what we do. It’s who we are 👫 We believe that geothermal heating is the key to a cleaner, greener future. But making it a reality takes more than just advanced technology. It requires expertise, dedication, and a deep understanding of what lies beneath our feet. Expertise isn’t just about technical knowledge, it’s about the people who bring it to life. Behind every step, a team of dedicated professionals turns knowledge into action. Whether engineers, geologists, drillers or business developers, each of them bring a unique perspective that drive innovation and progress at every stage. We are proud and grateful to have such talented people by our side every day. Geothermal energy is a reality. At Innargi, we have the team to make it happen. You can see some of the clever colleagues behind our work below Wojciech Prochaska Helen Cromie Jesper Royberg Natalia Krygier Emil Stürup-Toft Farid Taghiyev Edita Günel Martin Kaster Fiona Debelts Christian Vang Madsen Laura Nelson Marusic

Read more about us here: https://lnkd.in/d4HQh3x6

Travelling millions of years back in time and looking at the history of Aarhus 🌍 When we drilled our geothermal wells in Aarhus, we extracted long samples of rock from the reservoir, 2200 m below the city. In total, we cut 52 m of rock core from the Gassum Formation with the purpose to study the geology and the geothermal reservoir properties up close. It is the fine details in the geological layers of the core that give us important clues to what the environment looked like around 200 million years ago in the area around Aarhus. At that time, the area of Aarhus was covered by the sea. Sea level was rising and falling slowly through time meaning that sometimes Aarhus was lying deep under water and only fine mud was settling down on the sea bottom. Other times, Aarhus was closer to the coastline, and thick layers of sand were deposited. This activity caused permeable reservoirs, which is what enables geothermal water to flow under the city of Aarhus today. The geological layers in the core are not a continuous record of events. The changing sea level and the shifting of the coastline back and forth was a dynamic system where the material that was deposited one day could be removed the next. We are looking at small pieces of a very old puzzle with a lot of missing sections. However, sometimes even daily events are preserved, such as repeated layers of sand and fine mud, which is an image of how the tide streamed in and out. Our Subsurface Team uses the core data to build the architecture of the sandstone layers 2 km underground and model how hot water from the Gassum reservoir will flow through the underground to the first geothermal district heating plant in Aarhus, currently under construction. It also indicates reservoir characteristic we may expect to find in future locations in the city. Thanks to sedimentological expert Henrik Olsen, and to the helpful staff at PanTerra Geoconsultants BV core lab and GEUS core storage.

30 years of heat in Aarhus🔥   By the end of 2025, we’re set to deliver the first heat to residents in Aarhus, the second-largest city in Denmark. This marks the beginning of a 30-year commitment to provide reliable district heating for their homes. Over time, a new generation will grow up in these homes, learning that a significant portion of their heat is sustainably sourced from geothermal energy, a natural and circular source of energy deep beneath their feet.   Transitioning to more sustainable heating is a significant milestone for a community to achieve. It seems like one of the most obvious ways forward if we want to ensure we leave the planet in the best possible condition for those who come after us. Kredsløb in Aarhus is fully committed to this vision.   Now that’s a story to tell the next generation!   Below are five benefits that locals in Aarhus can look forward to as our geothermal plants begin supplying heat.

2024 was all about drilling - 2025 will be about delivering heat In January our drillhead reached the depth of 2.5 km at the harbours in Aarhus. We pumped the first hot water to surface, which had been lying in the ground for more than 200 million years. 3 wells were successfully drilled at two different geothermal sites in Aarhus as part of our appraisal phase in the first half of the year. This fall we have been exploring a route of 82 km in North Sealand, mapping the subsurface to find good places to drill for hot water in the future. As we continue to build on these successes next year, we will embrace a new task of 2025: harvesting and delivering our first heat to the district heating network in Aarhus. Before we press ahead, let’s take a moment to honour the incredible work achieved this year. We could not have done all the above without our smart, talented and hard-working Innargi colleagues and external partners. A very well-deserved Christmas holiday to everyone! Enjoy this inspiring roundup of our journey, captured from above. 🦅

🌍 An Early Christmas Gift for Geothermal Energy!   At Innargi, we’re thrilled by today’s Council conclusions on geothermal energy, unanimously adopted by EU energy ministers. This significant milestone underscores geothermal potential to secure stable, affordable energy while decarbonising heating and cooling across Europe.   As our Chief External Relations Officer, Asbjørn Haugstrup, aptly put it: “Geothermal has an enormous untapped potential in Europe and geothermal district heating can make a substantial contribution to achieving EU key strategic objectives: Reaching climate targets, eliminating fossil-fuel dependencies and achieving reliable and affordable energy prices by accelerating the roll-out of homegrown renewables.”   With geothermal projects already being introduced to cities, we’re committed to providing geothermal on an industrial scale. The call for an EU Geothermal Action Plan in combination with a strategy to decarbonise heating and measures like faster permitting, access to subsurface data, and risk mitigation tools is a step in the right direction to continue the rollout of this natural resource from under our feet.   Let’s keep the momentum going! Together, we can decarbonise heating, making a lasting impact across Denmark, Germany, Poland, Hungary, and beyond.   We are excited to unwrap this gift and get to work in 2025 🎁 Read the full article in the comments ⤵️