District heating and cooling
District heating is the most common heating form in Finland. We are forerunners of district heat production and as proportion to the population, Finland is the largest producer of district heating in the Nordics. Heat is produced locally close to the customers.
District heat production is aiming for a carbon neutral future
District heat is produced in combined heat and power production or solely as heat. In one district heat network, there are many power plants. This will help to adjust the production to the seasonally variable demand. Reserve capacity guarantees heat production also during maintenance outages and disruptions.
Depending on the power plants and regions, fuels used are wood or other biomass, coal, natural gas, peat, waste or oil. When choosing the fuel, it is important to consider the security of supply, overall financial and environmental impacts. Storability is important in the selection of fuels for production plants that are only used from time to time. The share of fossil fuels has been cut by less than half in the last ten years in the pursuit of carbon neutral heat production. Zero emission production already accounts for more than 60% of district heat production. In many municipalities only domestic fuels are used.
New production methods, different heat pumps and so called hybrid solutions where at least a part of the district heat is produced in other ways than combustion, are becoming more common. For example, industrial excess heat and heat from waste waters can be utilized in district heating. Also combined heating and cooling solutions create new business potential. New interesting trends are solar heat, so called two-way district heating and the utilisation of lower temperatures solutions. The possibilities of geothermal heat obtained deep from the Earth’s crust and seasonal storage of heat are followed with interest.
In district heating systems a large scale usage of renewable energy will be possible as heat generation moves towards renewable fuels.
Cost-effective and environmentally friendly district cooling
District cooling means the distribution of cooled water in pipes, produced in a centralised way, to several buildings where it is utilised for the cooling of ventilation. Centralised production enables greater unit sizes, which means that energy can be produced in a cost-effective way.
Compared with building-specific cooling, district cooling is also a more environmentally friendly choice. It is also a more competitively priced, carefree and reliable source of cooling energy.
Buildings using district cooling gain a number of benefits: the air- and structure-borne noises and vibration caused by cooling equipment are eliminated, the space for cooling equipment becomes free for other use, condensing units spoiling the façade of the building are no longer required, and the repair and maintenance of cooling equipment are no longer necessary.
District cooling is rapidly gaining popularity
District heating companies already provide district cooling in several towns in Finland. The operating principle can be compared with district heating with the exception that in district cooling the extra heat from the customer is transmitted to the energy supplier’s district cooling water.
The cooling need is caused not only by the sun, but also by the heat sources within the buildings, such as machinery, computers and other electrical appliances. Buildings may also have a cooling need simultaneously with heating needs in the cold seasons. District cooling energy can also be delivered for the cooling of industrial processes or manufacturing and storage facilities in the food industry.