As regards environmental issues, the key objects of reporting are the effects of operations on the climate and air quality. Emissions vary considerably from year to year. Helsingin Energia’s figures for 2006 were distinctly higher than the preceding year’s emission quantities which were lower than usual. In the annual fluctuation of carbon dioxide emissions in respect of electricity, the water situation of Norway is the decisive factor. At the beginning of 2006 there was little water in storage reservoirs, and some Swedish nuclear power plants were closed for repairs, due to which thermal power plants with higher emission rates were needed also in summer to cover power consumption.

High production efficiency

Energy efficiency is the main goal of Helsingin Energia’s environmental strategy. It is implemented in combined heat and power production, district cooling, and information on sensible use of energy.

Highly efficient combined heat and power production (CHP) accounted for 78% of generation of electricity in Helsinki. Helsingin Energia obtained 49% of its electricity from natural gas, 29% from coal, 16% came from shares in nuclear power, and 6% from renewable energy sources.

District heating satisfies almost half of real estates’ heating needs in Finland, and up to 93% in Helsinki. In 2006, CHP accounted for over 91% of district heating in Helsinki.

More significant than mere shares of raw material is the efficiency of net energy generation. The specific emission of carbon dioxide in 2006 was 320 g/kWh, while the figure for reference year 1990 is 400 g/kWh. Starting from the 1950s, Helsingin Energia has been engaged in eco-efficient cogeneration of electricity and heat. At the beginning of the millennium, a third element, production of district cooling, was added to this. Compared to decentralised solutions, district cooling not only saves space and energy, but also reduces emissions and city noise.

The efficiency of natural gas and coal power stations continues to be kept as high as possible. CHP also represents clean coal technology. At its highest level, it enables carbon capture and storage (CCS). This subject has come up throughout the world and was also looked into at Helsingin Energia.

Technology ensures environmental friendliness

Although emissions from power and heating plants in Helsinki have increased, efficient purification of flue gases has kept their impact on air quality insignificant compared to other sources. Jammed traffic and foreign terrain fires were evident in contaminant contents, and smoke could be felt in the spring and late summer throughout southern Finland. At measurement stations of the Helsinki Metropolitan Area Council (YTV), the contents of nitrogen oxides and particles were higher than in preceding years.

Along with fossil fuels, the role of renewable energy sources was discussed also at Helsingin Energia. In power supply, the aim is to increase the shares of hydropower, wind power and nuclear power. The need for district heating and the growth of new districts are so extensive that renew­able energy sources cannot offer any significant addition to Helsinki’s existing co-generation structure in the short term.

A new source of energy which the Katri Vala heating and cooling plant utilises in production of district heating and district cooling is the heat of purified wastewater. It is important to increase Finland’s already high proportion of biomass utilisation, but from the climatic point of view the location of its utilisation is not essential. For logistic reasons, biomass or waste energy should be utilised close to its place of origin. Helsingin Energia has a development program for renewable energy sources, which we update yearly.

Clean museum hydropower

Since May 2000, the re-repaired museum hydroelectric power plant in Vanhakaupunki district has generated ’environmental penny electricity’ for customers who have chosen it. At the turn of the years 2005–2006, problems were discovered at the museum hydroelectric power plant and the water turbine had to be repaired again. In spring, the power plant was commissioned and opened for museum visitors.