District heating is extremely resilient. Its usage dates back to over 100 years ago. Today it is a vital element in the development of sustainable cities.

Essentially, district heating systems make use of heat produced in central locations and distribute it through pipelines to a large number of end users. In this way heat, that  has no or very low value in one place, e.g. industrial surplus heat, can be transformed to high value, in places where there is a high
demand for heat, such as small towns or large urban communities.

Advantages of district energy compared to individual solutions

Individual heating solutions only allow  one specific type of fuel, e.g. coal, oil or natural gas. For the end user, this means that their heating bill is fully financially exposed to price increases of a specific fuel. With district heating, it is possible to take advantage of market forces driving price changes on different types of fuels. District heating also makes it possible to achieve other societal preferences and political goals, e.g. independence from fuel imports and CO2 targets. In short, it is much simpler to change fuel from, e.g. natural gas originating from one central place, than it is to change boilers in thousands of individual houses. Today, even electricity is used to produce heat, when prices reach virtually zero due to excess capacity from e.g. wind
turbines.

Flexibility is one of the key advantages

Production of district heating or cooling at central units gives access to several fuel types. This makes district heating production very flexible. In turn, this increases both the security of supply and production efficiency. Should one unit break down, there are alternatives available, where at any given time the district energy company can choose the cheapest fuel. Establishing a district heating network also permits the usage of low-quality heat in society. This could be surplus heat from industry and waste incineration, and heat from combined heat and power (CHP) production.

100 years old technology  – and still as vibrant as the first day

The world needs to increase focus onexploiting all available sustainable energy resources in the most optimal way. This means that advantage must be taken of surplus heat from any source, replacement of fossil fuels with renewable energy, such as solar and biomass, as well as ensuring systems integration between electricity and heat. The future will also increase the possibility to store heat from summer to winter in the form of large-scale seasonal storage.

District heating provides an answer to these challenges and should therefore be considered as the backbone of tomorrow’s urban communities and smart cities. The establishment of district heating can start on a small scale and over time gradually cover the entire urban community. Copenhagen is a good example. Here it all started with one small local system in 1903 and now 98 per cent of the city is supplied by district heating.