Ground source heating guide - What is ground source heating?

Ground source heating guide - What is ground source heating?

What is ground source heating?

Ground source heating is stored solar energy from fields and lawns, mountains and lake beds. A ground source heat pump extracts the energy and provides heating, hot water and cooling for your house or property. The ground source heat pump can also heat the pool.

Ground source heating and marine heat use the same type of heat pump. Which type you should have is determined by where you live and which house you have.

Rock heat works in most places and is an especially good choice in northern Sweden.

Ground source heat is a renewable energy source that uses little electricity to operate but gives more than five times as much energy back, allowing you to reduce your costs. 

How does ground source heating work?

The rock heat is extracted from drilled energy holes, normally about 200 meters deep. The fluid circulating in the system is cold but high temperatures are created by the heat pump inside the house. 

The house must have waterborne heating.

More than 300,000 houses and properties in Sweden have geothermal heating. However, there are - dare we say - some prejudices. A common myth is that the heat can run out in the rock. But according to the Geological Survey of Sweden (SGU), recharge occurs in the summer and continuously from below and from the sides of the rock.

Another common perception is that installing ground source heating is complicated, but CTC's partners take full responsibility for energy calculations, installation and operation. An experienced installer also protects both the lawn and the house facade. 

Installing geothermal heating - how to do it

Cost of ground source heating

Geothermal heating usually costs between SEK 100 000 and 200 000.

This affects the price:

- Energy requirements
- How deep you need to drill
- The type of bedrock
- The depth of the surface soil

The cost depends mainly on the length of the energy hole. The higher the energy demand, the longer the energy hole. For large properties, several energy holes are often drilled.

In southern Sweden, there are areas with calcareous bedrock, which reduces the effect, for example on Gotland. Some municipalities do not allow geothermal heating.

Your local installer/dealer will take all factors into account and give you a unique energy calculation with a quote. Find retailers where you live

Advantages and disadvantages of ground source heating

Advantages of ground source heating:

  • Renewable energy.
  • Increases the value of the house by between 3 and 12 percent, according to Booli.
  • Reduces operating costs by up to 85% depending on the current heating system.
  • Requires virtually no maintenance and has a long lifespan.
  • Can be used to cool rooms or as a pool heater.
  • Easily controlled via the Uplink app and a display with Swedish text on the heat pump.
  • You do not need a large plot of land to install ground source heating, but the drilling rig needs some space to move around.
  • The installation entitles you to a root deduction. The labor cost is calculated according to a standard, 35 percent of the total cost including the pump. Then the root deduction is 30% of that amount.

Disadvantages or limitations of ground source heating:

  • The distance between boreholes should be at least 20 meters. The distance to a house wall should be at least 4 meters. The distance to a water well should be at least 30 meters.
  • Soil with a high lime content is less energy efficient.
  • In northern Sweden, deeper boreholes are needed because of the cold.
  • Permission from the municipality is required.

    Installing a ground source heat pump - how to do it

Ground source heating compared to other heating systems

Comparisons are always good. Here we compare ground source heating with other common heating systems:

Ground source heating or district heating
Ground source heating is usually cheaper than district heat per kilowatt hour, but the price of district heat varies between municipalities. Rock heating is renewable while district heating can be fully or partially renewable depending on the municipality. Both heating systems are virtually maintenance-free and also provide hot water.

Ground source heating or pellet or wood boiler
Ground source heating is virtually maintenance-free, unlike pellet and wood boilers, both of which require work. Wood and pellets are renewable energy sources but burning wood can emit harmful air pollutants.

Ground source heating or air/water heat pump 
Unlike ground source heat, air-to-water heat pumps consist of an outdoor and an indoor unit. Ground source heat is suitable for those who do not want visible outdoor parts. 

If you live in northern Sweden, ground source heating is a better choice than air/water heat because ground source heat is not affected by the outside temperature in the same way. If you live in southern Sweden, the alternatives are more equivalent.  

An air-to-water heat pump can meet most household needs and is cheaper to install than geothermal heat.

Ground source heating or electric heat
Ground source heating is significantly cheaper than electric heat, which is by far the most expensive energy source. Electrically heated houses are rare today, except for holiday homes.

Installing ground source heating in seven steps

  1. Contact a skilled dealer
    The ground source heat installation must always be dimensioned according to your unique needs. To get everything perfectly adapted, you should always start by contacting a CTC dealer. The dealer is your most important contact before, during and after installation.

    The dealer is responsible for dimensioning, installation, execution, commissioning, adjustment, handover and instructions, either himself or through a subcontractor.

  2. Home visit and energy calculation
    The dealer will make an on-site assessment of the plot, bedrock, size and insulation of the house. You will need to answer questions about your heating and water needs today and in a few years' time. Which neighbors already have ground source heating? Are you planning to expand? Do you want to cool a room as well? Does the need for hot water sometimes increase so you should take that into account in the calculation? Or is air/water heating or geothermal heating a better option than ground source heating?

    The result is an energy calculation using a special program from CTC. Based on this overall picture that is unique to you, the dealer will calculate which CTC pump(s) are good options.

    The energy calculator will also show the estimated drilling depth, the annual efficiency, the estimated annual consumption, your expected savings and how quickly the investment will pay off. The energy calculation is tailored to your house or property and your heating, hot water and cooling needs.

  3. Clear quote for ground source heating
    A good dealer will also provide you with a clear quote that includes everything you need to know. Read the quote carefully and ask questions about what is and isn't included. 

    What costs might be involved? Will the garden and house façade be protected and who will restore the garden? There may be minor traces in the lawn after drilling and mud around the energy hole.

  4. All papers ready
    Get permission from the municipality and inform the neighbors. The retailer, or the subcontractor carrying out the actual drilling, must report the energy hole to the Geological Survey of Sweden (SGU).

  5. Drilling
    Now the installer comes with blankets to protect the lawn and house facade. Drilling takes a couple of days and the whole installation is completed in a week. Normally, electricity and water do not need to be turned off for more than a few hours.

  6. Commissioning: Now you can check in the app
    The heat pump is installed and the system is commissioned. The heat pump has a clear display in Swedish, but you should also download the MyUplink app with all the data in it. Here you see how much hot water there is and can quickly adjust if the need increases. You can set vacation mode when you are not at home. You see the temperature both inside and outside and the temperature of the water in the collector hose. In the unlikely event that something does not work, you will receive a push notification and an email. Full control! 

    If you have a pool or room with cooling, those temperatures are also displayed in nice graphs. And if the ventilation is connected and has sensors for humidity and carbon dioxide, it is also displayed.

  7. Return visit with adjustment
    The dealer will book a meeting after a month to make adjustments and ensure that everything is running smoothly. 

    Installing geothermal heating - how to do it

Life expectancy and care

A properly sized borehole lasts a lifetime. The collector tube has an estimated lifetime of up to 100 years. The service life of the heat pump is up to 20 years depending on how hard it is run. If the property's energy needs change, you can drill deeper into an existing energy hole or drill an additional energy hole. Make a new energy calculation!

Normally, the ground source heating system is completely maintenance-free.

<br>Life expectancy and care

Of course, we want you to feel completely safe with your purchase and with CTC. When you buy a heat pump from CTC, it is included:

  • Three-year product warranty on the pump.
  • Twelve-year hot water warranty on the hot water exchanger.
  • Six years of free security insurance from the day of installation on the entire system (5 years for legal entities). You can choose to extend this insurance to 18 years for a fee.
  • The insurance complements the home insurance and removes the deductible. Home insurance must have a mechanical damage section.
  • The dealer must be certified in plumbing.

The dealer is responsible for design, installation, execution, commissioning, adjustment, handover and instructions. 

Published: 2023-01-03