The release of the latest National Pollutant Inventory (NPI) data shows a fall in fine particulate emissions from coal-fired power stations for the fifth year in a row, while other emissions are in line with last year which was the lowest level for four years.
PM2.5 emissions fell 3.7 per cent and have fallen 21 per cent over the past five years and by nearly 46 per cent over the past decade. PM10 emissions are in line with last year (up 0.3 per cent),but are down around 22 per cent and 27 per cent over the past five and 10 years respectively.
In other results, NOx emissions are marginally lower (-0.2 per cent), the fourth consecutive year that reductions have been reported while SO2 emissions were slightly higher (0.9 per cent) after three years of falling emissions. Both are well down over the past few years (see table below).
The most notable change was in mercury emissions which were 10.9 per cent higher, after four years of falling levels. Over the past five years mercury emissions are still down by 7.6 per cent and by nearly 17 per cent over the past 10 years (see table below and trend graphs).
An Australian Energy Council spokesperson said the trends over the past few years are very encouraging and we should expect to see the overall levels fall further over the next few years.
“A range of factors can result in noticeable shifts in emissions, particularly year-on-year, such as demand and availability of plant. Plant performance will also depend on how often they are dispatched by the market operator.
“Given these factors while there can be year-on-year variations as a result of variability in individual plant performances, the critical data remains the overall sector trend and that continues to be positive. The Eraring Power station in NSW, for example, had an increase in fugitive particulate emissions predominantly as a result of operating plant and equipment involved in increased recycling of coal ash.”
The amount of electricity generated across Australia by coal-fired plants was 2.1 per cent lower in the same period.
“For many of the reported emissions electricity generation is also not the main contributor.
“The latest annual NSW Air Quality Statement showed that state had its cleanest air quality ever recorded last year and that the dominant factors in air pollution are natural causes.
While large industrial emissions, including power plants, are often cited as the key source of air pollution, this latest NSW report shows the principal factor in the good air quality last year was variations in natural sources as a result of weather patterns.
“Take particulate emissions. Natural sources are Australia’s predominant contributor but are not reported in the NPI data. An earlier NSW EPA Air Quality Study for the NSW Greater Metropolitan Region found sources, such as windblown dust and bushfires, accounted for 60 per cent of PM2.5 emissions, while 40 per cent came from man-made sources, and of those 31 per cent come from wood heaters, 26 per cent from industry, 19 per cent from road transport and only 17 per cent from power stations.”
“The important thing the NPI data shows is that across Australia’s coal-fired generation fleet the trendline for emissions continues to be good and this can be expected to improve as the energy transition results in a change in the grid’s generation mix.
“And operators continue to focus on meeting their licence limits and minimising emissions where they can.”
Overall reductions in past five and 10 years
5 years | 10 years | |
PM2.5 | -21.0% | -45.7% |
PM10 | -22.1% | -27.2% |
SO2 | -13.8% | -21.1% |
NOx | -17.6% | -22.7% |
Mercury | -7.6% | -16.9% |
Source: AEC analysis of NPI data
The five year graphs can be found here.
