District heating is the most wanted heating method in Finland and its popularity has further increased in recent years. District heating is selected as the heating method in almost 70% of new buildings. The share of heat pumps increased significantly in new buildings in 2010–2014, but their share has settled to less than 20% since 2014.
The environmental benefits of district heating are indisputable. Back in the early days, the proliferation of district heating had a significant impact on the improvement of air quality in cities when property specific coal and wood heating were abandoned. Nowadays, district heating networks enable the effective reduction of carbon dioxide emissions, and district heating emissions have been reduced by a fourth in total since the beginning of this decade. At the moment, approximately half of all district heating in Finland is produced without generating emissions. Already three quarters of district heating of the member companies of Local Power is emission-free.
The reduction in district heating emissions has been contributed to not only by the replacement of fossil fuels to renewable fuels but also by the connection of heat pumps, waste heat and heat reservoirs to heating plants and district heating networks. The heat pumps of power plants, which utilise heat from combustion gas, as well as the waste heat recovery from large data and shopping centres can reduce emissions with considerably higher efficiency than property-specific solutions.
Top class delivery reliability
In the scope of a reliable heat supply in cities and urban areas, district heating is a superior and equal solution to all customers. In 2017, the delivery reliability of district heating was 99.98% when taking into account all disruptions. When we also take into account the significance of the local energy companies on the local economy and their local owners as profitable companies and enablers of affordable energy to their customers (somewhat dependent on the company strategy), the significance of a local district heating system is undeniable.
Against this background, it is somewhat alarming that district heating is sometimes seen as an either/or alternative, for example, to heat pumps or the other “new” heat production methods. Among others, the former Minister of the Interior Mykkänen recently wrote that it is very common for entire blocks of flats to disconnect from the district heating network and start utilising geothermal heat and, in this manner, save on heating costs. This has also been considered among the residents of my own block of flats in Helsinki, but the investment in several geothermal wells is neither cheap nor risk-free technically or financially. I personally prefer to see my local district heating company invest in heat pumps and deliver low-emission district heat to me. The energy company has higher competence in this matter than our housing company – even though we are a smart group of people.
Key role of district heating in the future
District heating plays a key role when improving energy-efficiency. For example, air source heat pumps correctly installed to work alongside district heating in blocks of flats may bring significant reductions in heating costs. This, however, requires expertise and close collaboration with the district heating company. On the other hand, heat pumps are not necessarily needed at all in the world of affordable and emission-free electricity because the same amount of electricity can also be used to directly heat the district heating water with the help of electrical resistors.
It is, however, evident that there will not be any excessive availability of emission-free electricity any time soon which would allow the heating of all of Finland without fuel. Our country is not electricity self-sufficient; it is dependent on imported electricity. In such a scenario, it is vital to ensure that fuel is renewable, domestic and readily available. In the future, an interesting and efficient heat source may also very well be constituted by small modular reactors that are increasingly in the focus of research.
Therefore, district heating is not an alternative solution to the other emission-free heating methods; it actually works well together with them and by utilising them. For this reason, the district heating network will continue to be the heating infrastructure platform of responsible cities and urban areas, wherein heat energy is produced and introduced from different sources and wherein different heat flows are recycled and utilised in different ways. The lead role in this is played by the local district heating companies, many of which already apply locally adapted solutions, among other things, in utilising waste heat and waste flows. At the same time, the district heating companies continue to carry the responsibility for the delivery reliability and optimum performance of the whole system, which is easy and safe for the customer.
Almost half of the Local Power members carry out district heating business. District heating has a key role in the decarbonisation of heating and, therefore, our organisation will continue to follow and impact the discussion on the heating market even more actively.