In recent years, Waste-to-Energy (WtE) initiatives have emerged as both waste management solutions and drivers of technological innovation. In response to the climate crisis, WtE research efforts are concentrating on solutions for a greener, more energy-efficient future.

The following article highlights how Waste-to-Energy aligns with global sustainability goals, showcasing projects that explore the transformation of waste from odorous nuisance into an opportunity for sustainable living.

Waste-to-Energy & the Circular Economy

As the world’s population continues to grow, waste generation is projected to follow suit – by 2050, the total production of waste is expected to reach 3.40 billion tons a year, according to World Bank estimates.

To tackle this emergency, civil society is increasingly focusing on how waste is avoided, treated, and disposed of. WtE technologies play a key role in this effort, as they produce resources, or return them to the system in a circular way.

In the waste hierarchy, what cannot be reduced can be reused, and what cannot be reused can be recycled. Waste that cannot be recycled can be treated in WtE plants that convert it into energy or material for new products. Indeed, the bottom ash resulting from the WtE incineration process is a potential goldmine of materials such as copper, silicon, calcium, iron, aluminium, steel, sodium, magnesium, potassium, zinc, barium, lead, and— last but not least—silver and gold.

Once extracted from the bottom ash, these materials are reintegrated into the circular economy with practical and vital applications. They are essential to the green and digital transitions, as metals are key components in electronics, from laptops to smartphones, batteries, solar panels, and wind turbines.

In contrast, the extraction of raw metals is highly energy-intensive, emits significant greenhouse gases, and can negatively impact natural habitats, causing soil, air, and water pollution. In addition, raw materials are often extracted outside of Europe, so importing them into another continent further exacerbates their environmental impact.

How research is changing Waste-to-Energy

In spite of its positive impact, the shift in human behavior toward more sustainable waste management can only go so far if not accompanied by scientific innovation. WtE research plays a crucial role in this effort by striving to maximise WtE plants’ energy and heat production while minimising polluting emissions,

Waste heat recovery technologies, for example, provide an additional boost to the green transition by amplifying the overall energy efficiency of WtE plants. Heat recovery projects capture the heat generated by the incineration of waste and, instead of allowing it to dissipate, repurpose it and channel it into district heating and industrial processes.

Tapping into this promising field of research, ESWET recently set up a new task force to explore the full potential of heat recovery and its multiple applications.

Notable examples of heat innovation include coupling heat recovery from flue gas treatment systems with carbon capture technologies. An initiative by Waste-to-Energy company AVR, for example, harnesses CO₂ emissions from waste incineration. Once captured from the WtE process, the CO₂ emissions are repurposed and put to good use in horticultural greenhouses, reducing reliance on natural gas.

Other WtE projects, instead, combine waste incineration with carbon capture technologies – this system not only mitigate greenhouse gas emissions, but also enhances WtE facilities’ environmental performance. In 2025, for example, a new project combining decarbonisation with the circular economy will contribute to the design of an innovative carbon capture plant in Mustasaari, Finland. The WtE plant will be equipped with a system capturing all the carbon dioxide from the flue gases produced during waste incineration. In a subsequent step, the carbon dioxide from the Mustasaari facility will be liquefied and employed in the production of synthetic e-fuels from green hydrogen and carbon dioxide.

Another innovative process transforms air pollution residues from WtE plants into materials for the construction sector. The system accelerates the reaction that naturally occurs between waste and carbon dioxide. Reducing the reaction time to minutes instead of months or years results in the creation of calcium carbonate (manufactured limestone) that can be used for building purposes.

A different declination of WtE research concentrates instead on the potential of waste incineration to eliminate Per- and Polyfluoroalkyl Substances (PFAS), which pose a threat to both human health and the environment. A pilot study by researchers in Europe and the United States shows promising signs that incineration can eliminate the majority of PFAS materials produced by the WtE process.

Waste-to-Energy facilities turn into attractions for local communities

In recent years, two outstanding WtE projects in Europe have helped to increase public awareness of waste incineration facilities. With their unexpected architectural features, the Copenhill and Spittelau incinerators showcase the versatility of WtE plants to a wider public, highlighting how WtE can be a resource for local communities.

Since 2017, CopenHill (also known as Amager Bakke) has changed Copenhagen’s skyline. This unlikely mountain in the middle of the Danish capital is a WtE plant as well as a popular attraction for visitors near and far. What makes it so? A dry skiing slope, rooftop bar, trekking and walking ground, and the world’s climbing wall.

When still in its infancy, the Copenhill project details were made available to the local community and integrated into the municipality’s plan. This open communication with civil society allowed residents, WtE experts, and NGOs to add their own input to the venture, instead of standing by passively as they saw it take shape. Today, the same dialogue continues with the local community: residents living a few hundred metres away from Copenhill are kept up to date about any of the plant’s activities that may impact their daily lives and conflict with their interests.

Elsewhere in Vienna, Spittleau – the brainchild of Austrian artist Friedensreich Hundertwasser – looks nothing like your typical WtE plant. With its creative, multi-coloured design, the imposing structure has become an architectural gem in the heart of the Austrian capital. The facility boasts a “double life”: while Spittelau burns waste and turns into energy, guided tours take place inside the facility.

Conceived for both children and adults, the Spittelau tours provide insights about the unlikely marriage between waste and architecture, peppered with engaging details about the often mysterious WtE process.

But not all WtE plants need to be works of art or display exceptional features to elicit people’s interest. Tour groups are also on offer at Dublin’s WtE facility, also known as the Poolberg incinerator. The visits raise public awareness about the plant’s activities and attract different groups of people, from school students to local organisations and government officials, among others.

Waste-to-Energy and job creation

If well-designed, WtE projects can support local economic growth, and provide quality employment opportunities by involving residents in construction, operation, and management.

A 2022 UN Economic and Social Council report explores WtE technologies’ contribution to the circular economy as well as their potential to create social and economic value for local communities.

Dublin’s WtE facility, for example, became operational in 2017, the result of a public-private partnership involving the local municipality and private companies. The plant employs over 100 people who are responsible for its daily operations.  An additional 300 job opportunities arose during the plant’s construction phase, drawing workers from the local community.

Elsewhere in Azerbaijan, 900 people were hired during the construction of a new WtE facility in Baku, and 90 currently work inside the plant.

When new WtE plants are built, they also offer trainings for residents and the opportunity to find an employment in the facility.

Attracting investment in sustainable technologies

The climate change emergency, rising world population and energy demand are bringing unprecedented opportunities for growth in the sustainable waste management.

Governments and regulatory bodies are offering financing instruments, eager to improve WtE plants’ performance, environmental safety, health standards, and decrease dependence on fossil fuels.

The global WtE market is expected to expand considerably, from 44.3 billion in 2023 to over 70 billion US dollars by 2030, according to a new report by consulting company Global Market Insights. The same study predicts a 6.9% growth rate in the WtE’s thermal technology sector by 2030.

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