Monitoring the air quality in Helsinki
The impacts of Helsingin Energia’s power plants on air quality have been monitored systematically for decades. Monitoring is carried out by the Helsinki Metropolitan Area Council (YTV) and the Environment Centre of the City of Helsinki. Helsingin Energia also monitors the impacts of its operations itself with regular measurements.
Improved air quality
Long-term emissions monitoring indicates that the air quality in Helsinki has clearly improved in the past decade. Bulk deposition of the coal-fired Hanasaari and Salmisaari power plant areas has fallen to about half (3−5 g/m2/month) of the 1980s values (7−9 g/m2/month). In the Salmisaari power plant area the bulk deposition is at the same level and in the Hanasaari plant area almost at the same level as at a distance of 0.5−1 km from the power plant areas.
The desulphurisation plants and electrostatic precipitators of the power plants and reduced use and improved storage and handling of coal have played a key role in the improvement of air quality.
What do bulk deposition, sulphate deposition and combustible substances mean?
Bulk deposition consists of flue gas particles from power plants, suspended particles in ambient air (e.g. pollen and dust caused by traffic), handling and storage of coal, and the impact of atmospheric humidity and rain. Rain has a significant impact on bulk deposition because, for example, rainfall of five millimetres within a short period of time removes about half of the suspended particles. The origin of bulk deposition cannot be established with the monitoring method in use.
Sulphate deposition is derived from sulphur dioxide produced from various fuels, from sulphur trioxide bound to fly ash, and from short or long-range transport of pollution. The impact of power plant flue gases on sulphate deposition can be assessed on the basis of correlations between power plant emissions and environmental sulphate depositions.
The sources of combustible substances include uncombusted particle emissions from flue gases, coal stores, and dusts from outside the power plant area, the share of which cannot be separated with deposition monitoring. By comparing the depositions of combustible substances and the particle emissions of power plants, the contribution of various sources in the deposition of combustible substances can be estimated on the basis of correlation.
Climate calculator
TKK Dipoli, WWF Finland and Motiva Oy have jointly developed an online service, which can be used by offices and events to determine the carbon dioxide emissions produced by their operations and to obtain information on their reduction. With the calculator, it is possible to estimate the carbon dioxide emissions arising from electricity and heat consumption, passenger transport, goods transport and paper consumption. The service also provides tips on emission-reduction measures and procedures.