Why Waste Landfill Energy?
Last spring, one of India’s largest rubbish dumps – the Ghazipur landfill in the outskirts of New Delhi – erupted into flames during a record heatwave. The 65-meter-tall rubbish mountain spewed smoke across densely populated neighborhoods. A nearby resident lamented: “Our cities are crumbling under the weight of their own waste.”[1]
A few months later, the sole rubbish dump in Kampala, the capital of Uganda, collapsed after weeks of heavy rain, burying adjacent houses and dozens of sleeping residents.[2] The garbage dump landslide at the site serving a city of 4 million people was a “disaster bound to happen,” according to the mayor.
Besides such widely reported disasters, long-smoldering fires, toxic seepage, and other environmental issues at landfills are all too common. News of local protests at poorly managed sites can be found not just in developing countries but elsewhere from Alabama to London.[3]
Such trash problems are likely to mount, if unchecked. The United Nations Environmental Programme (UNEP) estimates that between 2020 and 2050 municipal solid waste generation per year will nearly double from 2.1 billion tonnes to 3.8 billion tonnes.[4]
Currently some 40% of all this waste is “uncontrolled,” either dumped into the environment or openly burned. Such open waste is set to double if current practices continue.[5] The problem is particularly acute in fast-growing economies which have not or cannot afford to invest in waste facilities, even as their populations grow.
Mismanaged waste visibly threatens local health and safety, but equally problematic is how decomposing waste generates methane, an invisible and odorless gas 80 times more potent than carbon dioxide in terms of its ability to warm the planet.[6] Scientists estimate that methane emissions contribute to a third of global heating and that a fifth of these emissions are from decomposing waste, primarily in unmanaged open-air landfills.[7]
Last year, satellite data revealed methane emissions from landfills to be much larger than thought. Many of these sites are causing “super-emitter events.” For example, a satellite flying over the Ghazipur site in March of 2024, prior to the fire, recorded methane emissions from the open landfill equivalent to the climate impact of the annual emissions of 350,000 US cars.[8]
To stop such runaway impacts of trash, a UNEP report on household municipal waste highlights the priority to “halt waste growth and to shift towards zero waste and circular economy models.”[9] As the world works towards more reduction, reuse and recycling, however, one important transition technology is already effectively transforming rubbish into a resource: waste-to-energy (WtE) plants.
Modern WtE plants incinerate waste at extremely high temperatures, treat emissions and leave minimal amounts of toxic byproducts, all while reducing the volume of waste and generating heat and electricity. Some 1,700 of such plants are found worldwide, most of them in high-income economies. Japan, with its dense cities and limited space for landfills rapidly expanded WtE technology since the 1990s[10] and currently maintains 700 of them.[11]
Though such plants globally generate only about 1% of renewable energy, in countries like Germany and Japan the rates are much higher, at somewhere around 5% of total electricity production.[12] Sweden, a country renowned for very high levels of recycling and stringent environmental regulations, burns most of its household waste to generate district heating to 1.5 million households and 780,000 with electricity, in a population of some 10 million.[13]
Thermal WtE is attracting attention in growing economies that face mounting waste disposal problems but also energy shortages.[14]
Yokogawa, a technology leader for industrial processes, hopes to improve efficiencies for WtE plants around the world. The company has a track record of providing various control, monitoring and maintenance system solutions for waste and biomass power plants which generate a total of 3 GW of power across the world to ensure their efficiency and profitability.
In 2022, Yokogawa purchased Dublix Technology ApS, acquiring the Danish company’s combustion control and boiler performance technology that helps to improve the combustion process. This is particularly important as household waste has varying characteristics in its physical dimension, chemical composition, calorific value and moisture content, contributing to fluctuating amounts of steam to turn the turbine, resulting in unstable power generation. The low calorific value and high moisture content of waste particular to developing countries is a critical technical challenge for adoption of thermal WtE.
Yokogawa and Dublix technology promise to overcome that bottleneck. More efficient combustion will also mean less emissions of nitrogen oxides (NOX) and other harmful gases, while improving availability, efficiencies and profitability of the plants. In 2023, the company successfully conducted a performance test at a WtE plant in Krakow, Poland where it demonstrated a 2.5% (equivalent to 5,500 tons annually if the plant operates at full capacity) increase in waste incineration, while keeping emissions within government-set limits and ensuring optimal operation of the steam turbine.
The company hopes to bring these solutions to rapidly growing economies like India.
Currently the Modi administration is implementing the Clean India Mission with plans to hygienically treat all waste in the approximately 3,000 landfills around the country by 2030. The government has set aside over $500 million to clean up at these landfills, including Ghazipur, by installing new waste facilities and disposal methods based on circular economy principles.[15]
To this end, WtE and biomass energy plants can reduce waste volumes hygienically and with less climate impact, while easing India’s chronic and worsening electricity shortages.[16] The Indian government estimates that WtE plants can provide potentially 5 GW of energy, almost 30 times more than the capacity installed today, across the country.[17]
In addition to expanding its WtE technology, Yokogawa recently bought a minor stake in Singaporean Ideation 3X, a waste management company with a track record of sorting and recycling of waste as well as generating high-quality alternative fuels from plastics in India. The two companies hope to synergize and provide solutions for India’s “integrated solid waste management” – a comprehensive, sustainable, and strategic approach to managing all aspects of solid wastes to maximise resource use.[18]
Providing cutting-edge solutions for industrial process, including the disposal and use of waste and biomass, to make the planet smarter and more circular is Yokogawa’s vision for the future. And it appears the company is wasting no time to get there.
