We manage society’s waste and recycle energy from it.
We reduce greenhouse gas emissions and environmental toxins in the environment by using waste –which for various reasons cannot or should not be recycled – to produce electricity and heat. In this way, waste incineration becomes an effective complement to material recycling. We also strive to increase the amount of waste that is sorted for material recycling and therefore investing in new sorting facilities.
Until a few decades ago, most waste in Sweden was dumped in landfill, but in 2002 a comprehensive landfill ban was introduced – and for good reason. The EU has also decided that the days of landfill are numbered, but this will take some time. In most EU countries, waste still ends up in landfill to the tune of 100 million tonnes a year.
There are three important reasons why landfill is the worst possible way to dispose of waste. Firstly, dumping organic waste in landfill creates methane – a greenhouse gas that is 28 times more powerful than carbon dioxide. Secondly, waste often contains heavy metals and other environmental toxins that can poison groundwater and lakes. Thirdly, in the vast majority of cases, sending waste to landfill means that the waste’s potential as recycled raw materials or energy is not utilized.
If landfill is the worst possible destination for waste, perhaps it makes sense to not create waste in the first place. In between these two ends of the scale, there are several different ways to manage waste, including energy recovery. The so-called “waste ladder” shows a hierarchy of different approaches.
Stockholm Exergi’s waste sorting guide:
We produce heat and electricity at our waste-fired CHP plants, and ensure that heavy metals and other hazardous substances do not end up in the environment or in new products.
When we incinerate waste, toxic and environmentally hazardous organic substances are destroyed. We purify materials that do not burn – such as heavy metals – in several stages in which we capture virtually all remaining material. So, we can say that our facilities function rather like society’s kidneys by removing dangerous substances.
This function will become increasingly important over the long term. As society becomes better at sorting and recycling materials, our waste-based fuels will increasingly consist of materials that cannot or should not be reused.
The use of Carbon Capture and Storage (CCS) and Carbon Capture and Utilization (CCU) in the final phases of residual waste treatment in conjunction with energy recovery is one potential approach. This would capture carbon dioxide that could be either stored permanently, (with CCS), or processed into a new raw material, (with CCU). Final treatment of residual waste with incineration and energy recovery, supplemented by CCU, where carbon dioxide is processed into a new secondary raw material, would take the circular economy to a new level.
Sweden is one of the best countries in the world at waste management. This is because we are good at sorting and recycling materials and energy. This is something that many Swedes contribute to and should be proud of.
But we need to be better – especially in terms of sorting and recycling fossil plastics. Random samples taken in 2020 showed that household and industrial waste from the Stockholm region contained 18 per cent plastic by weight. Sixty per cent of household CO2 emissions generated by waste are caused by plastic packaging, (and paper packaging with plastic content), that should have been sorted and sent for material recycling instead.
If all the plastic in Stockholm’s household and industrial waste was sorted, CO2 emissions from waste management with energy recovery would be reduced by 325,000 tonnes – equivalent to six months’ car emissions in Stockholm.
The most important measure to reduce emissions from plastics is to reduce the use of fossil plastics in general, and to increase sorting in households and businesses. Sorting waste mechanically also offers considerable potential.
Therefore, together with waste management company SÖRAB, we have built a large-scale post-sorting plant at Bristaverket, with a capacity of 140,000 tonnes of household waste a year. We will sort plastic, metal and organic waste at the plant so that they can be recycled or digested to produce biogas. The facility has received support from the Swedish Environmental Protection Agency.
Today, we take it for granted that consumer products flow across national borders. What eventually becomes waste in Sweden may have been produced in another country, based on components from a third and raw materials from a fourth. These value chains are often even more complex. In the same way that globalisation has highlighted the advantages of specialisation within borders, we need to collaborate across national borders to manage value chains in their entirety. Waste incineration is an important part of the global circular economy and Sweden is ideally placed to make a significant contribution.
Many of our neighbouring countries lack the waste management capabilities available to us here in Sweden, for example district heating networks or systems for sorting and recycling household waste. It will take time for these countries to establish these systems and until then, millions of tonnes of rubbish will end up in large landfills.
For every tonne of waste that we treat from other countries instead of being dumped in landfill, global emissions are reduced by between 290 and 570 kilograms of carbon dioxide. The reduction is due to the avoidance of emissions from landfills, our replacing fossil fuels in Swedish district heating, and the production of electricity that competes with fossil electricity in northern Europe. Furthermore, waste incineration reduces the use of virgin raw materials.
In some countries, the alternative is not landfill but power generation. Even then, however, our solutions offer considerable advantages because we use a much larger proportion of the energy content in waste, enabling us to supply district heating and electricity from the same amount of waste.
Naturally, just as in Sweden, waste in other countries should be sorted and recycled in the first instance. The waste we import to be used as waste-based fuel consists primarily of material that cannot be recycled rather than household waste.
Stockholm Exergi mainly uses waste from municipalities in the Stockholm region because the local waste system is dependent on us. But when we have sufficient capacity, we also offer our waste management services to other European countries.
We have two waste management plants, one in Brista and the other in Högdalen.