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Managing Waste: Are developing nations leapfrogging with new toilet solutions?

130830 ecosan.eng.alt
130830 ecosan.eng.alt

When it comes to the management of human waste, we tend to break the world into two segments: the developed world, with flush toilets, and the developing world, with little infrastructure or access to sanitation services. Solutions for the developing world are a high priority because the risks of under-performing sanitation systems – disease and death – are extremely high. But the solutions emerging today for the developing world could have important implications for resource use and waste management throughout the developed world as well. We recently had a chance to talk with representatives from two organizations bringing sanitation systems to developing economies, SOIL (Sustainable Organic Integrated Livelihoods) and Loowatt, about their waterless systems that convert wastes into valuable resources—the SOIL EcoSan Toilet and Loowatt, respectively.

Since 2006, SOIL has been developing business opportunities related to providing sanitation services, using their EcoSan toilet models.  Customers rent the toilet unit and pay a collector to remove accumulated wastes for composting at a centralized facility. The composted material is then sold for profit, and used to improve agriculture as well as reforestation. The solution improves health, agriculture, and the environment, while building local economic opportunities. (Learn more here.)

Toilet_White Background
Toilet_White Background

Loowatt similarly offers a self-contained toilet system, but the collected wastes are converted on-site into a biogas that can be used for fuel, and compost that can be used as fertilizer. Loowatt systems have been piloted in communities in Madagascar that lacked centralized collection and management of wastes, but they have been specifically designed to deliver a standard of odorless and hands-off sanitation that meets expectations of residents of Western countries. (For more information, visit Loowatt).

The concept of "leapfrogging" in sustainable development typically refers to developing nations skipping steps in technological development, jumping ahead to advanced technologies. For example, countries adopting cell phones without ever having built infrastructure for landlines. At first glance, it might seem that these toilet solutions are low-tech. But are they the more advanced option? They don't rely on billion dollar, energy-intensive wastewater facilities or similarly expensive infrastructure for transporting water to and from homes for flushing. The systems convert what can be burdensome—and hazardous—waste into resources with monetary value. And they don't require water.

The Bullitt Center in Seattle is a six-story building that uses composting toilets to meet design requirements of the Living Building Challengefor water self-sufficiency. Designers installed 10 aerobic composters in the basement where the waste accumulates and begins to break down. Material that isn't converted into carbon dioxide and water vapor is picked up monthly and taken off-site to a commercial compost facility where it is further broken down for use as fertilizer.

As pressure on water supplies intensifies and energy and fertilizer costs climb, will developed nations seek toilet solutions like those being implemented in the developing world? What infrastructure will support a shift toward waterless solutions and who will build it?


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Resource Fix: Irrigation Pumps from Kickstart International

KickStart is a non-profit social enterprise with a mission to take millions of people out of poverty quickly, cost-effectively, and sustainably, using a private-sector business model focused specifically on irrigation for small-scale farmers in Africa.

Eighty percent of the poor in Sub-Saharan Africa are rural farmers who live on small, low-productivity farms, grow insufficient food to properly feed their families, and earn just enough money to survive, but not enough to escape poverty. KickStart identifies profitable business opportunities open to these farmers, and then designs, manufactures, markets and sells simple tools to create profitable family farm enterprises that rely on irrigated rather than rain-fed agriculture.

Credit Esther Havens

Kickstart’s portable irrigation pumps enable farmers to pull water from shallow wells or surface sources using manual power, without the use of fuel. The pumps increase the acreage that can be planted year-round, while more efficiently using far less water than channel or flood irrigation methods. Irrigation enables farmers to grow multiple cycles of high-value crops throughout the year, generate higher yields, and harvest and sell crops in the long, dry, “hungry season” when prices are highest and spoilage related to market saturation is less likely. (Typically 50 percent of rain-fed crops are spoiled before they are eaten or sold.)

KickStart’s solutions address a number of interconnected problems simultaneously. They increase agricultural productivity, alleviate poverty (generating income to pay for many basic needs, including children’s education), reduce food wasted due to spoilage, and increase food security for rural African communities. Moreover, KickStart is using an innovative strategy (Mobile Layaway) that leverages mobile money technology to help farmers save for irrigation pumps using a convenient, low cost, and secure micro-payment service, and has plans to use farmer training to increase the efficacy of its programs.

KickStart is also focused on using fewer resources in the pumps themselves. The newest pump, the MoneyMakerMax (MMM) is 22 percent lighter, about 10 percent more water efficient, and more rust-resistant than its predecessor, and is designed so that twice as many pumps can fit into a shipping container, reducing resource use and costs associated with transportation.



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There are 23,000 potential sites for Rentricity's hydrokinetic energy recovery systems in the U.S. alone

400 Billion gallons of water run through pipes each day. The moving water has to be slowed down with pressure reduction valves, creating friction and wasting energy

Given the availability of precise measurements for flow rates and pressure, in-pipe hydro is  more predictable than wind or solar energy

Currently, 20 % of water flowing through pipes is lost to leakage. Rentricity's solution offers better leak detection for improved water quality and conservation

RENTRICITY’S renewable energy technology, which captures wasted energy in water pipelines and generates electricity, has potential to offset much of the energy used to circulate water and wastewater in municipal and industrial systems throughout the world.
Innovation Summary

400 billion gallons of water run through pipes each day, half of which is used in energy generation primarily for cooling, a quarter of which is used in agriculture, another 50 billion gallons for personal use, and 50 billion gallons for industrial use. Most of this water is gravity-fed. The moving water gains speed and pressure and has to be slowed down with pressure reduction valves, creating friction and wasting energy.

Rentricity currently deploys two in-pipe hydro energy recovery systems, Flow-to-Wire and Sustainable Energy and Monitoring Systems (SEMS) to convert excess pressure in water pipes into clean electricity. These systems generally include a micro-turbine, generator, sensors, processors, electronic controls, and communications equipment. The electricity produced can either be sold to the electric grid or used behind the meter to offset water systems’ energy requirements, which account for 4 percent of electricity consumption in the U.S. (7 percent globally).

Given the availability of precise measurements for flow rates and pressure within water systems, in-pipe hydro provides a more predictable power supply than other renewables, like wind or solar energy. This consistent in-system electricity generation could provide power for distributed water treatment to increase water quality. It could also power sensors for better leak detection. About 20 percent of water flowing through pipes is lost to leakage, so having a way to detect leaks in more remote sections of water systems could make a significant difference in water conservation.

There are 23,000 potential sites for Rentricity’s hydrokinetic energy recovery systems in the U.S. alone, including industrial and wastewater treatment systems, mandated small dam releases, and water transfer stations, and a significant amount of water infrastructure is currently being built or repaired across the globe. Rentricity envisions a world where all water and wastewater pipes undergo an “energy recovery audit” to identify potential opportunities.


The central idea behind Rentricity’s technologies is to capture energy that’s being wasted and convert it into usable electricity. That, in and of itself, is a dMASS strategy. But Rentricity has greater potential to address multiple problems within a complex system.

First, Rentricity’s systems currently bypass water pressure reduction valves (PRVs). Eventually, the company may develop a “pressure reduction turbine” to both generate electricity and perform the function of a PRV, thereby replacing the need for two separate pieces of equipment. Already, the technologies rely primarily on pre-existing infrastructure. Second, Retricity’s technology provides an energy source closer to the end point of water systems, which could enable more effective, distributed water treatment, as well as power distributed sensors to detect leaks. Finally, Rentricity’s technology comes at an important time. America’s water infrastructure is in disrepair, with hundreds of billions of dollars going towards replacing and upgrading pipes and valves that were put in place up to one hundred years ago. Worldwide, new infrastructure is being built at a rapid pace. Placing an energy harvesting system within these new water systems now will provide a significant source of power and will build resiliency into the systems.


Rentricity was founded in 2003 and has received funding from state energy agencies in Connecticut, New York, and Rhode Island to test and develop its technologies. The company has installed systems in two water treatment plants in the Pittsburgh region and one in Keene, New Hampshire, and another four systems will come on line in 2013.