Since the 1973 oil crisis Denmark has concentrated on producing electricity from the combustion of coal, the aim being to ensure a multifaceted system and the greatest degree of supply security. Coal is also attractive because it is a cheap source of energy. Most Danish power stations currently use coal, although they to a certain extent supplement this with natural gas.
The EC has laid down precise and wideranging rules on pollution from power stations and other large combustion plants (50 MW and over) through Directive 88/609 supplemented by Directive 94/66. The essence of the regulations is that new plants (after 1 July 1987) shall comply with emission requirements for SO2, NOx and dust that in practice are only attainable by abatement measures. In addition, old plants shall together comply with certain national quotas that are being reduced stepwise as the years go by. For Denmark the starting point in 1980 was 323,000 tonnes SO2 and 124,000 tonnes NOx. The corresponding figures for 1998 are 141,000 tonnes SO2 and 81,000 tonnes NOx.
Denmark started a quota system for SO2 from power stations in 1984, this being the type of pollution then in focus because of the acidification of Swedish lakes. The idea of the system was that SO2 pollution was to be reduced considerably over the 20 year period to the year 2005, but that the power stations were to be allowed to decide where they would implement abatement measures first in order to optimize the effort financially.
It was not necessary to draw up a special programme concerning dust. In this respect abatement measures had already been initiated in the 1970s, and the technology was well known and cheap.
In 1989 NOx was included under a quota scheme according to the same principles as for SO2. However, the Danish system deviates from the EC quota system in that it includes all power stations, both old and new.
The EC emission requirements to new combustion plants have been implemented under Danish law through a Statutory Order. However, the Danish requirements are more stringent than the EC requirements with respect to emissions of both NOx (200-225 mg/m3 versus 350-1,300 mg/m3) and dust (5-50 mg/m3 versus 50-100 mg/m3).
Slag and fly ash (dust) from the incineration of coal and waste is to a considerable extent recycled to building and construction work. Their use is closely regulated with regard to the place of use and the thickness of the layer. It is also a requirement that the lead content of the material shall be less than 3,000 mg/kg, the cadmium content less than 10 mg/kg and the mercury content less than 0.5 mg/kg.
Progress on the power station front has been as follows:
SO2 pollution from power stations has fallen from 216,000 tonnes in 1980 to 130,000 tonnes in 1992. According to the time schedule - which has so far been followed - this should fall to 45,000 tonnes by the year 2005.
NOx pollution has fallen from 122,000 tonnes in 1986 to 82,000 tonnes in 1992, and according to the plans should reach 42,000 tonnes by the year 2005.
Some remarks about total emissions of SO2, NOx and CO2 would seem to be appropriate here.
The total Danish emissions of SO2 amount to approx. 200,000 tonnes per year (1992 figure), of which 70,000 tonnes is derived from sources other than power stations. The starting figure in 1972 was 500,000 tonnes. Denmark has had no difficulty in fulfilling its obligations under the first SO2 Protocol of the 1979 Geneva Convention, i.e. to reduce emissions by 30% between 1980 and 1993.
Denmark has signed the second SO2 Protocol wherein requirements to Contracting States are based on the levels tolerable to nature. Denmark is obliged to reduce emissions by 80% in relation to the 1980 level by the year 2000. This will necessitate marked intervention in respect of all groups of polluters in addition to the reduction schedule already planned. Denmark has chosen to try to attain that goal by means of a SO2 levy of DKK 10 per kg SO2 emitted that has been introduced with effect from 1996 (for further details, see Section 12.3.5). The levy is expected to increase flue gas abatement and the use of natural gas so much that total emissions from all sources are certain to fall to less than 100,000 tonnes SO2 per year by the year 2000.
Total Danish emissions of NOx amount to 274,000 tonnes per year (1992 figure), of which 185,000 tonnes is derived from sources other than power stations. Relative to the peak in 1986, there has been a reduction of 40,000 tonnes, nearly all of which is attributable to abatement measures at power stations. Under a Geneva Convention NOx Protocol, Denmark is committed to reducing emissions by 30% between 1986 and 1998. This obligation will undoubtedly be fulfilled, in part due to abatement measures at power stations, and in part as a result of the introduction of catalytic converters on cars (obligatory on new cars from 1 October 1990).
Total Danish CO2 emissions currently amount to approx. 60 million tonnes per year, the figure having been roughly constant for the last 20 years. The EC has the declared policy that emissions in the year 2000 should be held down at the 1990 level, which is also the goal set by the 1992 Climate Convention. Denmark has ratified the Climate Change Convention, and in addition is aiming at a 20% reduction in CO2 emissions by the year 2005.