Reduced / Sequestered
(To Implement Solution)
In a sustainable world, waste would be reduced from the outset and composted, recycled, or reused. The current reality, however, is that cities and land-scarce countries face a dilemma about what to do with their trash. Waste-to-energy is a transitional strategy for a world that wastes too much and needs to reduce its emissions.
Incineration, gasification, and pyrolysis are means of releasing the energy contained in trash. Some of the heavy metals and toxic compounds latent within it are emitted into the air, some are scrubbed out, and some remain in residual ash. With these outcomes, why bother at all? Waste-to-energy plants create energy that might otherwise be sourced from coal- or gas-fired power plants. Their impact on greenhouse gases is positive when compared to landfills that produce methane emissions as organic wastes decompose.
At Project Drawdown, we consider waste-to-energy a regrets solution. It has a positive impact on emissions, but social and environmental costs are harmful and high. It can help move us away from fossil fuels in the near-term, but is not part of a clean energy future. Even when incineration facilities are state-of-the-art (and many are not), they are not truly clean and toxin-free.
The negative externalities of waste-to-energy are diverse, but it has also some benefits: 2–3 gigatons of greenhouse gases emissions can be avoided by 2050, due to reduced methane emissions from keeping waste out of landfills and replacement of electricity generation from conventional fossil fuel technologies. Considering the disadvantages, this is a transition solution—one that will decline as preferable waste-management solutions, including zero waste, composting, and recycling, become more widely adopted globally. Island nations, with limited available space, may continue to use waste-to-energy as an alternative to landfilling—employing more advanced technologies, such as plasma gasification, to limit the negative impacts. Nevertheless, generation of electricity from waste to energy plants could grow from the current estimated 140 terawatt-hours to 210–490 terawatt-hours, depending on 2050 total electricity generation needs.