How do I know if geothermal heating is a viable option for our housing company?

Geothermal heat is often an energy- and cost-efficient solution for heating and cooling even larger residential buildings. However, geothermal heating isn’t suitable for all housing companies, and the very first requirement is a hydronic heating system, i.e. radiators or underfloor heating that circulates water. The most common barriers to geothermal heating are the housing company being located over an aquifer, underground structures under the plot, opposition from the housing company’s shareholders, or a plot that is too small to accommodate a sufficient number of geothermal wells. These most common barriers are also the most important issues to be addressed when a housing company initially starts considering a transition to geothermal heating.

Find out if your property is suitable for geothermal heating

The first thing you should do is check with the city to see if your housing company is in an aquifer zone that prevents wells from being drilled or if there may be underground structures under your property that would prevent geothermal heating. You can easily submit your preliminary inquiry regarding the feasibility of installing geothermal heating on your property in Helsinki using the city’s online form. Helsinki has also allowed the use of public land for geothermal heating if your plot is insufficient.  If you’re considering the possibility of using public land for a geothermal project in your building, ask about it in the preliminary inquiry.

There is a common misconception that geothermal wells may not be drilled on a leased plot. However, the City of Helsinki is generally very positive about geothermal projects on the plots it leases. If your housing company is located on a plot leased from Helsinki, you must ask the city for permission for the geothermal project during the implementation phase in accordance with these guidelines.

Involve shareholders in discussions at the outset

Remember that the attitude of the shareholders towards geothermal heating will determine whether or not the project moves forward. So, you should find out how shareholders and residents feel about the idea and consider how to proceed accordingly. It’s a good idea to start discussions early when considering a geothermal heating project, as active communication in housing companies has been shown to help implement these projects.

It’s important for all shareholders to understand that a geothermal renovation will pay for itself, unlike a plumbing renovation or painting the roof, for example. Shareholders and residents are often concerned about the impact of a geothermal project on their yards and gardens. However, a geothermal heating system has little impact on using the yard, other than during the drilling of geothermal wells and the installation of pipes. A geothermal project can be a great opportunity to improve yard areas.

It’s also worth correcting some common misconceptions about geothermal heat: Housing companies still often believe that geothermal heating is somehow a new technology, even though here in Finland, we have more than 30 years of experience using it, and Sweden has been using it much longer. In Helsinki, hundreds of housing companies have switched to geothermal heating. The technology is also quite simple and actually quite old: the operating principle of a geothermal heat pump is the same as that of a conventional refrigerator. Others may also be concerned about the lifecycle of a geothermal heating system or fear that the heat will run out or the wells will freeze. However, when a system is designed well and sized correctly, this cannot happen. In addition to providing heat for the heating system, geothermal heat is also sufficient for heating tap water.

Hire an expert to work out the details

If geothermal heating seems feasible for your housing company, it’s a good idea to hire a specialised company at this stage to take a closer look at implementing it. For example, there must be adequate space for geothermal heating equipment. The expert will also determine whether there is room for geothermal wells on or near the site and whether the bedrock and soil are suitable for drilling the energy wells. Typically, energy wells for apartment blocks are around 250–350 m deep and several wells are needed depending on the building’s heat consumption and other heat sources, such as heat recovery from exhaust air. You can find experts in our list of service providers, for example.

An energy expert who is independent of any equipment suppliers can also help with requesting tenders and selecting a contractor. They can also advise on whether a geothermal project should be accompanied by other measures, such as additional insulation in the attic or smart thermal management to reduce energy consumption. Once the location and number of geothermal wells are known, a more thorough feasibility study should be carried out for the City of Helsinki. Please read the detailed instructions on geothermal heating in Helsinki on the city’s website.

There are several options for financing the project

To carry out a geothermal heating project in a housing company, the company will naturally also need financing. There are several financing options for this kind of project, but the most typical is for the housing company to take out a loan. Banks also offer green loans, and some companies offer geothermal energy through leasing financing, for example. Geothermal projects can also be financed with the savings gained with geothermal heat, so in many cases they can be carried out in a cost-neutral way, as the loan repayment is covered by the resulting savings.

Geothermal heating is not the only option for energy renovations

If it ultimately turns out that geothermal heating is not appropriate for your housing company, there are fortunately many other measures that can reduce your housing company’s housing costs and save energy, such as:

• Air-to-water heat pump (AWHP)
• Exhaust air heat pump (EAHP)
• Heat recovery ventilation (HRV)
• Solar panels
• Improving the thermal insulation of the building envelope
• Intelligent controls for building technology and checking the settings
• Balancing and flushing the heating system
• Replacing old ventilation fans
• Water-saving plumbing fixtures and nozzles
• Pressure-reducing valve for the domestic water line
• Informing residents about energy-efficient habits

So, geothermal heat is certainly not the only option, and you can carry out an energy renovation without it. Before starting a geothermal heating project, it’s also always worthwhile to reduce energy consumption through other measures. This will avoid making the geothermal system unnecessarily large and expensive.

Take advantage of free and impartial advice

For more advice, please contact the City of Helsinki’s free and impartial energy advice service for housing companies. You can also explore energy renovations carried out by other housing companies on our website.