ISWA White Book on EfW technologies : "Energy from Waste will take care of the waste that cannot be reduced, reused or recycled"

ISWA’s Working Group on Energy Recovery will soon publish its new White Book on Energy-from-Waste Technologies. The report, which has been three years in the making, is an in-depth analysis of what energy from waste (EfW) is, its contribution to a sound and safe waste management system, and the technologies used in the sector. In the White Book, the authors aim to offer assistance to those involved in developing waste management systems, especially decision makers in countries where EfW has not yet been established or is only in its early stages.

Johnny Stuen, chair of the working group, talks about the key findings of the report, the role of EfW in a circular economy and future technical developments.

Who is the target audience for the White Book and what are its main goals?

Decision makers in waste management are the main target audience, along with everyone who works in the field of waste management.

What are the main areas on which the publication focuses?

The mechanisms that must be in place so that you can choose the right waste management solution for you and especially the parameters that you must know before you choose a solution. It also gives a broad overview of the different technology solutions that are available in WtE/EfW.

The report moves away from the term waste to energy and instead uses energy from waste. Why is that?

It’s more of a linguistic difference, but EfW is generally considered more positive than WtE. There is no real difference between them.

What are the main advantages of EfW?

It will take care of the waste that cannot be reduced, reused or recycled into products and new raw materials, and turns those resources into energy. In addition, it is a very clean technology that can act as a final sink with very few emissions (much less than landfill or other solutions) and it’s much more strictly regulated than any other industrial process.

Why is EfW preferable to landfilling?

Because landfilling will always have a larger carbon footprint, it will also have a much larger physical footprint, and the resources are buried instead of converted into energy and recyclable materials as from the bottom ash.

Which countries are at the forefront of implementing EfW plants?

Sweden, Denmark, the UK, the Netherlands, Germany, Norway, Switzerland and China. There’s also very good development in Finland, Austria and Japan.

How can low- and middle-income countries that do not yet have many if any EfW facilities benefit from the installation of EfW plants and what steps are necessary to install a sustainable waste management system including EfW?

First, you need a good waste management system, where the ownership and responsibility for the waste is clearly defined in all phases. EfW is only a part of such a system, where collection is the most important thing together with a very clear final sink strategy. Investment is high, so a skilled workforce and suppliers are also necessary to maintain these plants for 30 to 50 years. It is also vital to be able to deliver electricity to the grid and to utilise the heat.

Related article: Waste-to-Energy in a Circular Economy: Friend or Foe?

EfW requires high funding capacities. What are the recommendations for the industry to be able to cover these costs and how long does it take for a plant to make a profit?

The income scheme is usually comprised of a gate fee and an energy income. The planning on how to finance the gate fee is important, and that must of course take into consideration the alternative cost – not just the operating cost, but also the long-term cost of things such as landfill or other solutions. The importance of very high availability and dependability must be given high priority, as waste will be arriving every day over the lifetime of such a facility.

Regarding profitability and sustainability: is it preferable to use a technology that requires pretreated or untreated waste?

The technology itself does not really care, but the cost of the waste management system will always increase with more treatment, regardless of whether or not the recycling rate goes up. From a resource and circular standpoint, pretreated waste is to be preferred.

Why are alternative technologies such as gasification, pyrolysis and plasma not yet regarded as viable options and how do you see the future for these technologies?

Many of these technologies do not have such a broad spectrum as the standard grate technologies. This means that they require more pretreatment and end treatment, such as sorting or grinding beforehand, and a special solution for the fractions that come out on the other side, such as a small incinerator for the residues and so on. All these extra steps have a cost and add uncertainty and downtime to the complete chain.