Helsingin Energia - Annual Report 2008

Environmental impacts

Emissions at their lowest for decades

Helsingin Energia's emissions continued to decrease in 2008. Coal consumption decreased by a third from 2007, the use of natural gas increased by approx. 9%, and the use of oil fell below 2% of total energy.

Carbon dioxide emissions decreased by 16% and were smallest for decades. The specific emissions of carbon dioxide of the energy sold declined by about 17% and totalled approx. 240 g CO²/kWh.

In the 2000s, the specific emission of carbon dioxide from energy sold by Helsingin Energia has varied between 240 and 330 g CO²/kWh. In the international reference year 1990, carbon dioxide specific emissions were about 400 g CO²/kWh.

Acidifying emissions of sulphur dioxide and nitrogen oxides decreased in 2008 by weight compared to 2007, sulphur dioxide by about 50% and nitrogen oxides by about 11%.

The permitted emission limits, determined on the basis of specific emissions, first entered into force at the start of 2008 as monthly limits. Some difficulties with the emission limits were experienced, mainly at separate peak-load and reserve heating plants.

Microparticle emissions totalled approx. 160 tonnes in 2008. In the 2000s, emissions have varied between 160 and 720 tonnes per year. Microparticle emissions collapsed at the beginning of the 1990s.

In addition to climate protection, the local air quality must also be taken into account in new energy solutions. The common project of the Finnish Meteorological Institute, the University of Helsinki, the Ministry of Transport and Communications, and Helsingin Energia on investigating the quantity, quality and origin of microparticles in the city air started in the operating year 2008. The Kumpula measurement station has produced real-time information since last autumn. The results also show that the flue gases from power plants and heating plants are kept under sufficient control.

In the last few years, thanks to district heating, thermal load on seawater has not been detected in the mandatory monitoring of sea areas. In 2008, the thermal load on seawater totalled about 300 GWh. In the 2000s, thermal load has varied between 300 and 2,200 GWh.

The annual average of sulphur dioxide content at the Vallila measurement station was historically low, only 2.3 μg/m3. This fell clearly below the limit of 20 μg/m3 set for the protection of the ecosystem. At their present level, fluctuations in sulphur emissions have very small impact on the quality of air in Helsinki. Prior to wider introduction of district heating in the 1950s and 1960s, ten times higher sulphur dioxide contents were common in the centre of Helsinki.

By-products of combustion

Combustion by-products include bottom ash and fly ash generated in a combustion process as well as solid desulphurisation product from a desulphurisation process. These can be employed for improving the quality of cement and asphalt and in earth-moving. Utilisation of combustion by-products was in 2008 complicated by the quality of the ash. In the operating year 2008, combustion by-products were pre-registered according to the EU Chemicals Regulation (REACH).

Exceptions

The availability of the desulphurisation plants in 2008 was good. At Salmisaari it increased from the preceding year to 96%, while Hanasaari maintained the good 97% level.

In the Hanasaari territory, massive alteration operations were performed during 2008: demolition of the Hanasaari A power plant, soil restoration, and construction of a new heating plant.

In the Salmisaari underground coal store, a smouldering fire broke out in September 2008. In connection with the store's ventilation, smell of smoke and hydrogen sulphide spread in the Ruoholahti district.

Exposure to electric and magnetic fields close to high-voltage overhead lines came up in connection with a change of location of a play park in the Kulosaari district. According to studies, magnetic fields caused by overhead lines are very weak, which was also established in this area. According to the authorities, radiation safety reasons gave no cause for changing plans concerning the play park.

Radio frequency radiation from remote-reading meters also came up. The impact of such radiation is a fraction compared to fields generated by mobile phones, moreover, the meters are not located close to people.