In Finland and Sweden, the energy company Adven has produced dozens of environmentally sustainable solutions based on geothermal energy, or geoenergy, for companies. According to Juhan Aguraiuja, the Head of Baltic Business, studies are being diligently conducted to determine whether the new environmentally sustainable energy type is also suitable for use in shopping and logistics centres, spas and new urban districts in Estonia.
Geothermal energy is generated when solar energy is stored in the ground or as heat radiating from the Earth’s core to the surface. For example, while geothermal heat pumps in Estonia currently use geothermal energy close to the surface, there may be significant potential in obtaining heat energy from hundreds of metres below the surface, which is increasingly used in Finland and Sweden.
Geothermal energy requires large areas for boreholes and a low-temperature heating system in the building. It is therefore potentially most suitable as a local heating or cooling solution for shopping and logistics centres, spas, commercial and residential districts, for instance. Underground boreholes, or energy wells, work like a battery: the heat stored in them in summer can be used for heating in winter.
The energy company Adven has built dozens of solutions using geothermal energy for various commercial buildings and city districts in Finland and Sweden. The company’s largest solution based on the new energy source has been built in the Lippulaiva district developed by Citycon in Espoo, where CO2-free geothermal energy is used for heating and cooling buildings. More than 170 geoenergy wells have been installed at a depth of more than 300 metres beneath the Lippulaiva urban centre.
In addition to environmentally sustainable heating, the new energy solution also provides cooling in summer. “Thanks to geoenergy, bedrock also provides cooling and there is no need for separate electric water cooling machines or roof condensers. We are delighted that Adven can be a trailblazer in geoenergy solutions for large-scale real estate projects and contribute to the fight against climate change,” says Timo Koljonen, Vice President in the field of real estate energy solutions at Adven.
Geothermal energy can also be used in hybrid energy solutions
Energy obtained from the ground can often be combined with, for example, solar energy and waste heat recovery. Adven is using a hybrid energy solution at the S-Group’s logistics centre in Sipoo, which is the largest building in Finland. Almost a third of all food and consumer goods in Finland pass through the centre, and the rooms have a wide range of temperatures between +5, -9 and -40 °C. To ensure that the storage conditions for food and other products meet all the requirements, the centre, which is almost 200,000 square metres in size, requires a lot of heating and cooling.
Adven planned a hybrid energy solution for the logistics centre, combining bioenergy and geothermal energy, cooling and waste heat recovery. A system was designed where geothermal heat from geothermal wells and condensation energy from cooling equipment cover as much of the need for low-temperature thermal energy as possible. Additional pellet fuel capacity, in turn, provides sufficient energy as the need for heating increases in winter and oil can be used as a back-up fuel in a heating network with a higher temperature. “We combined Adven’s knowledge in the field of cooling and heating with the client’s geothermal wells and, by integrating separate systems, we created a very interesting hybrid solution,” explains Henrik Vasama, Account Manager at Adven.
Geothermal energy also provides heating and cooling for the Skanssi shopping centre located in Turku, Finland, where Adven operates the energy solution. “Heating is an area with a significant climate impact. Switching to geoenergy has reduced our annual CO2 emissions and has also resulted in financial savings,” notes Maarit Hurme, Director of the Skanssi shopping centre, adding that it is important for real estate investors to be able to forecast the expenses of several years, and this is ensured by the price stability of geothermal energy.
Potential of geothermal energy in Estonia should be revealed by 2024 at the latest
In neighbouring Finland, heat can be extracted from rocks at a depth of 200-300 metres, whilst in Estonia you have to drill to a depth of 500-600 metres to reach rocks with reasonable heat storage capacity. The Geological Survey of Estonia is carrying out a thorough study to explore the potential of using geothermal energy in Estonia. The multi-year study will be conducted until the end of 2024 and will involve the construction of the first geothermal energy pilot plants.
“There is potential in Estonia, but we are carrying out tests and analyses concerning the depths and temperatures at which it is possible and effective to capture the energy stored in our ground,” says Juhan Aguraiuja, Business Manager of Adven Baltics. “Then, it will become clear whether we can use reasonably costed geothermal energy in Estonia. At Adven, we are following the developments in research and we certainly wish to offer our customers in Estonia and elsewhere in the Baltics new climate-friendly solutions, using our broad expertise.” According to him, we should have a rather clear picture of the local potential of geothermal energy by next year at the latest.