Anders Wilhelmson
Ashoka Fellow since 2009   |   Sweden

Anders Wilhelmson

Anders Wilhelmson is changing the way in which people in poor and crowded urban communities with inadequate sanitation facilities deal with human waste and offering a more dignified daily life.…
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This description of Anders Wilhelmson's work was prepared when Anders Wilhelmson was elected to the Ashoka Fellowship in 2009.


Anders Wilhelmson is changing the way in which people in poor and crowded urban communities with inadequate sanitation facilities deal with human waste and offering a more dignified daily life. Working closely with such communities, he is providing new opportunities through single-use, biodegradable toilet bags to turn human waste into wealth and solve one of the most intractable problems in such areas.

The New Idea

Anders has created a single use, biodegradable bag that can be used as a sanitary toilet in areas where no other sanitation is available. His innovation is intended to provide more dignified options for people who lacked toilets, and tackle global health challenges posted by poor sanitation. His innovation sanitizes waste and creates a closed loop sustainable waste management cycle, turning the waste into a lucrative resource of viable fertilizer, while also producing employment opportunities and putting communities in charge of their own services. His work goes beyond an incremental improvement to turn waste into wealth, meeting an intractable sanitation problem in a manner rooted in the context of the problem. The temporary solution improvised by community residents used waste plastic bags as ad hoc “flying toilets”—Anders’ innovation creates portable alternatives to infrastructure based facilities. He is building a for-profit company that also creates incentives for waste collection—a lucrative job option for micro-entrepreneurs to collect the bags and sell them as fertilizer. Through the collection program he is creating outlets for communities to construct informal municipal services. Anders is setting up a fluid, flexible alternative infrastructure that can be employed in emergency situations as well as permanent communities of the world’s largest slums, building sanitation solutions around the realities on the ground.

The Problem

Roughly 2.6 billion people across the world do not have access to dignified sanitation. Currently, over 1 billion people live in urban slums—a figure that has increased from 715 million in 1990, and is expected to double by 2020. Infrastructure is not keeping pace with the expanding informal settlements, which rarely have water and electricity as well as sanitation. Lack of sanitation infrastructure leads to water contamination, a primary risk for typhoid, diarrhea, and other intestinal diseases that ravage 1.8 million people with bacterial infection and are significant contributors to child mortality. Bringing in sanitation infrastructure is difficult in many areas—financial limitations are compounded by scarce water, lack of roads, limited waste management expertise, corruption, and a reluctance to “formalize” informal settlements.

Faced with no other options, citizens of some informal settlements improvised a solution that offers privacy and expediency, but at a terrible cost—the “flying toilet.” A vast surplus of polyethylene plastic shopping bags are used to contain waste, and are then thrown into alleys, roads, or simply out the door, as far away as possible. The bags land on roofs, in walkways, clog drainage systems, and the contents leak into houses during the rainy season. Settlements are plagued with plastic detritus. The UNDP reported that two in three people in the Kenyan slum of Kibera—the largest informal settlement in the world and the launch point of Anders’ work—used the flying toilet as their primary sanitation. The waste of whole communities goes flying through the air as a standard practice.

Other sanitation options, aside from being few and far between, have their own set of limitations. Flush toilets are rare and use increasingly precious water. Pay toilets—built more and more in informal settlements—are expensive, occasionally dangerous, and rarely open after dark. Often, they are located far from homes, creating a perilous situation for many women walking long distances alone to reach them. Eco-san toilets that separate and compost waste do not produce hygienically safe soil until two to three years have passed. These solutions are valid, but many are economically unsustainable and slow to gain traction as the dangerous root practices remain.

Finally, much of agricultural production in the developing world—particularly in Africa—either does not have a tradition of fertilizer use, or is dependent upon expensive mineral fertilizers imported from the western world. Crops diminish due to malnourished soil, and production shortages bring a whole host of other problems. More than half of those who lack toilets live in areas with large potential for agricultural cultivation, and many cities and city dwellers are engaged in some sort of small scale agriculture—a garden patch or otherwise. Sixty percent of all food in Nairobi is cultivated within city borders. It has been stated that Sub-Saharan Africa has the human waste to fertilize every field in the region, but not the know-how to convert it and bring it to fruition.

The Strategy

Anders is tackling the sanitation challenge by taking an existing, temporary waste disposal method created by people with no other options—the flying toilet--and making it a sustainable alternative in communities where permanent structures such as water pipes, water closets, and sewage treatment plants, are nonexistent or ineffective. Flying toilets are a reality in areas where there are no sustainable options. Many sanitation programs combat the practice through infrastructure projects such as pay toilets, water lines, or composting latrines, but progress is slow, construction is expensive, and many of the projects necessitate the slow shifting of intractable cultural perceptions about toilets and waste. Anders has built his work around what people actually do every day, and transformed it into a safe practice with a financial incentive. He is transforming the negative habit of the flying toilet into a resource that can help address problems beyond poor sanitation, but also lack of employment and low-yield agriculture.

After careful thought, Anders engineered a markedly simple, biodegradable bag—the Peepoo bag—that replaces the scrounged plastic shopping bags in large-scale use for waste disposal. Ander’s bag, patented in Sweden in 2008 after undergoing rigorous scientific testing, sanitizes its contents to remove the public health threat and provides a means for dignified collection, and a mechanism to transform the waste into fertilizer.

Made of fully biodegradable bioplastic, the Peepoo bag breaks into carbon dioxide, water, and biomass. The plastic, in part constructed of wax and lime, is produced using nearly half renewable materials and is moving towards 100 percent renewable. The bag has an internal membrane layer that is lined with urea, a nonhazardous chemical that is one of the most common fertilizers in the world. The use of urea in the bag was an untested and unevaluated innovation until 2003, at the onset of the project. In designing the bag, Anders was inspired by the historical example of Louis Pasteur and his work with the pasteurization. Milk was once called “the white poison,” and in order to render it safe, Pasteur discovered that it must be pasteurized by heat as quickly as possible, and then contained and enclosed. Anders’ bags perform a kind of pasteurization of waste, following those principles. The urea initiates an enzymatic breakdown when in contact with waste and limited heat, creating hygienic contents as it breaks down. Waste pathogens, initially contained in the two-layer plastic, are rendered harmless in two to four weeks. The bags can be disposed of without risk of contamination, as verified through tests by the Swedish University of Agricultural Sciences. The design of the bags also means that they do not smell.

UNDP requirements for effective sanitation interventions include: isolation of waste from individuals, preventing contact between waste and flies and animals, and the “inactivation” of pathogens such as bacteria, worms, and parasites. Anders’ work, built on years of research and field tests, has built a bag that meets the criteria and has proven effectiveness for usage.

The bag is simple and biodegradable. Once dug into the ground, it decomposes within three to eight months, creating a complete, natural fertilizer including nitrogen, phosphorus, and potassium. The result is comparable to a commercial chemical fertilizer and mimics successful practices adding nitrogen to fields to increase yields. The bags create a sustainable cycle of land-to-land at a lower cost than existing fertilizer, allowing fields to be enriched for half the price.

Beyond the technical innovation, Anders is creating new systems of community-based infrastructure to tackle waste collection after his bags are put to use. He has established a system of community waste management that can be applied anywhere the bags are used, and created a “closed loop” sustainable system. Local micro-entrepreneurs run businesses to sell the bags and collect them once used. Anders researched peoples’ willingness and ability to pay, and offers a subsidized price of US$.02 per bag (reduced through subsidies from US$.05.) Microfinance organizations help subsidize the nine gram bag, and local entrepreneurs sell them door-to-door. The point after usage also provides another entrepreneurial opportunity to collect the used—and scentless—bags and sell them as fertilizer. In this way, communities are put in charge of addressing their own sanitation woes, and economic incentives as well as dignity and quality of life keep motivation high. Regular fertilizer is also primarily sold in bulk, making it difficult for smaller-scale farmers to buy limited amounts.

Designed as a for-profit company, Peepoo was commenced through pilots funded by international citizen sector organizations, and is engaging existing distribution channels established by COs on the ground to expand their reach. Beginning with pilots in Kibera, Kenya, Anders is expanding work into Bangladesh and has 240,000 bags a day projected net capacity for his production units. The project is receiving wide attention from organizations focused on sanitation provision in emergency situations as well as more permanent settlements—UN-Habitat hopes to provide bags for more than two million Pakistani refugees currently living in Nepal.

The Person

Since he was six, Anders knew that he wanted to be an architect, and wanted to build things from the ground up. From the start, his buildings “did not look like everyone else’s,” and he became a somewhat controversial figure in the field, gaining a reputation as a free thinker. He began to realize that architecture can be inherently political. He was fascinated by the uses of space, and the rights that revolve around it--who has access and who does not—and how societies address the challenges of “contested spaces,” such as slums. He began to craft a theory on “contested space,” that landed him a prestigious char at the Royal Academy of Fine Arts, a rare achievement for a “young, long-haired thirty-something.” He began to break down the barriers of academia, opening up his experimental architecture courses to writers and artists, and building a new travel initiative that brought students on forty trips to various cities across the world, meeting people where they live from Cairo to Las Vegas. His focus on “contested spaces” altered the priorities of the Royal Academy, and sparked an altogether new initiative on informal urban development, and conferences on Informal Cities in partnership with citizen sector organizations.

In 1988 he founded a company, Wilhelmson Arkiteter AB, which offered product design to urban planning and guided large Swedish companies. He was surprised to find a unique client request—over 1000 people from a working class neighborhood combined savings to hire him as an architect to help them craft a thirty-year growth plan in their gentrifying location. Covering everything from new street names to longer-term growth strategy, he worked closely with the community to meet their needs, and emerged with a toolkit for community-owned community management, ready to expand it nationally. He was placed in charge of the complete relocation of the community of Kiruna, one of Sweden’s northernmost towns above the Arctic Circle, built around a mine threatening physical and economic collapse. Anders’ engineered the relocation and rebuilding of the town in a new area, designing lay out, transition, and infrastructure.

While on a trip to Mumbai with his architecture students, Anders visited street dwellers, remarkable examples of people living out his “contested space” theories. The women told him, “We don’t need architects—we know how to build.” He realized that the women did not need helping in this regard—they could buy water, negotiate leases, create shelter, but their enterprise could only reach so far. They did not have sanitation and could not create it from scrap. Sanitation was their one issue that remained most dominant, the challenge unmet. Anders made a bet to his students that he would figure out that major urban problem. The students promptly forgot the bet. With his partner Camilla, Anders began to craft the new idea that would become the Peepoo bag.

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