This will help sensitize the next generation of decision makers to the opportunities inherent in the circular economy

That’s how Guy Hutton, senior advisor at UNICEF and previously senior economist at the World Bank, describes a recently published book filled with insights on different ways to harness valuable resources from waste. In it, WLE scientists profile 24 innovative business models for using waste to fulfill the world’s need for fertilizer, water and energy.

Safely and wisely managing waste is one of several challenges offered up by rapid urbanization. Scientists recently estimated that the use of untreated urban wastewater for irrigation is 50% more widespread than previously thought.

Unfortunately, treating all wastewater is out of reach for many developing countries, and therefore scientists have been studying various business models that leverage private capital to address waste management challenges by turning waste into wealth.

All these business models are based on existing cases, including a WLE-supported public-private partnership in the city of Tema, Ghana, that turns fecal sludge and organic waste into safe compost pellets. The compost can replenish starved soils in and around the city, closing nutrient loops between urban and rural areas, while providing an incentive for waste collection. Other similar  partnerships are currently taking off in Ghana, India and Sri Lanka.

Scientists are also advising governments on how to tackle waste challenges, helping for example to revise the National Sanitation Policy in Sri Lanka to include options for safe waste recovery and reuse.

Waste can also be harnessed for energy, relieving pressure on forest and land resources. In and around Kenyan refugee camps, researchers trained women on how to produce briquettes from waste scraps. Provided with an alternative energy source, women are free from the hazards of seeking fuel far from their homes.

Using waste to sustainably intensify agricultural production can help make urban food supply more resilient. Other options for city planners include diverse food sources, including using short supply chains, and finding ways for businesses to contribute to city region food systems through new enterprises and public-private partnerships in production, processing, logistics, recycling and more.

Only when tapping into the principles of circular economy and applying them at scale will a thriving ecosystem be able to provide for current and future urban dwellers.

WLE’s partners in this work include IWMI, RUAF Foundation and ICRAF.​