District cooling is a byproduct of Helsinki Energy’s combined heat and power production. Heat energy from electricity production is used to produce district heat in winter and district cooling in summer. In winter, district cooling is produced with sea water. Utilising absorption technology, district cooling replaces the conventional, energy-intensive compressor technology. The estimated life time of the absorption equipment is 30-50 years; that of a compressor system is 15-20 years.
When a building is connected to district cooling network, it doesn’t need separate electrical compressors. That means a remarkable reduction to the use of electricity and also to the noise levels. The need of cooling is increasing even in cold Finland, because of the warmer summers and especially because of numerous computers that creates heat to offices and computer halls.
Helsinki is one of the world leaders in combined heat and power (CHP). More than 90% of Helsinki is heated with district heat. Savings in fuel compared to separate production are over 30% and carbon dioxide emissions are 35% lower. Air quality in Helsinki has improved remarkably thanks to CHP: since the 1990s, dust emissions have been reduced by 84%, the sulphur dioxide emission by 74%, and the nitrogen oxide emission by 60%. The technique has been copied in many cities worldwide. Thanks to its policies, Helsinki earned the UN Environment Award in 1990.
The Greens are the second biggest party in Helsinki, and they have a very strong influence in everything that the city does. Although the district cooling system has not been a Green’s idea, they have made a strong influence on energy policies in the city. Greens demanded that Helsinki Energy have to diminish its CO2 emission by 20% by the year 2020, which is now the official goal and the next challenge for Helsinki.
The text was provided by Ville Ylikahri, a green member of Helsinki City Council and a Secretary General of the Finnish Green foundation ViSiO.