Appropriate Technology Design Team

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The Appropriate Technology Design Team (ATDT) is a group of MEs, EES and other product development professionals who provide engineering design and research assistance for projects in developing communities throughout the world. The team works with in-country partners to design for local conditions so that solutions are appropriate and sustainable in the community. The implemented solution empowers communities by providing tools that facilitate local economic development and provide basic needs, local education, and entrepreneurial opportunities.

Fog Harvester

The Appropriate Technology Design Team (ATDT) is working with Themba Develoment Project to collect and distribute clean water through the design and implementation of a fog harvester or alternative method. Themba works at the community level to empower the residents to take charge of their own development to address hunger and food security, water/agriculture, skills development, and education. The ATDT fog harvesting device will improve the accessibility of drinking water in the community and may provide a supplementary source of economic opportunity.


Design, fabricate, test and deploy a fog harvester and affiliated distribution system to the community with local adoption of manufacture, operation, and maintenance.

Design Details

  • Leverage design of existing devices with specific changes to meet local geography
  • Affordable, durable, reliable and simple design
  • Minimal operation and maintenance needs

The Need

A community of roughly 900 people located an hour outside of Queenstown, South Africa has a shortage of clean water for drinking, agriculture and sanitation. The location is very dry, and there is not a sustainable amount of water available or methods to provide it. Currently, residents walk to community tap stations on an as-needed basis for water that runs from a small underground spring. The water quality is uncertain and the quantity available is unreliable throughout the year. The local government used to truck in water, but no longer has the resources to support these villages. The community needs water to sustain life by fighting hunger, dehydration through lack of available water supply, and to maintain a clean and healthy community. Foggy weather conditions common to the area during most of the year can be used to help mitigate this problem through fog harvesting systems, benefiting the community with necessary water resources.

Our Partner The Themba Development Project

Rock Crusher

The Appropriate Technology Design Team (ATDT) is working with A Single Drop to develop and fabricate a device capable of crushing rocks down to a size appropriate for bio sand filters. A Single Drop has helped form local water organizations that implement bio sand filters to communities in need of clean water. The Rock Crusher would enable the local water organizations to expand into communities without access to sand appropriate for bio water filters.


The project aims to create, test and potentially implement a working prototype which will be delivered to A Single Drop with the manufacturing specifications for local production.

Design Details

  • Output to be used to filter water in households of 6 -10 people.
  • Each filter to use approx. 26 liters of 0.19mm to 0.38mm sand.
  • Desired Crusher output: 2 liters/hour.
  • Jagged particles filter better than smooth-round particles.
  • Target cost: $500.
  • 5 to 10 Rock Crusher deployed in the 1st year with more each year.
  • Fabrication and maintenance to be done local to village.

Our Partner: A Single Drop

A Single Drop (ASD) is a non-profit organization working to unite communities by creating and/or strengthening people's water organizations to cultivate peace. Through technological trainings, community development programs and interactive presentations and performances, ASDs goal is to empower communities to proactively and collectively address their own local freshwater issues efficiently and sustainably.

Composting Toilet

The Appropriate Technology Design Team (ATDT) is working with Outreach International to develop a low-cost, easy-to-manufacture urine-diverting dehydration toilet that can be used in various rural locations where modern plumbing is not readily available. In addition, a dehydration toilet provides a free source of fertilizer (a commodity which is often fluctuating in price). The team will also work with Outreach International on training materials for the local community.


The project aims to research composting technologies to discover the most appropriate design for the local community. The team will build a working prototype to test and ultimately deploy to one of the rural villages.

The Need

Outreach International selected the community because the toilets in the community are crumbling and overflowing, resulting in the contamination of a nearby well. Outreach field staff have even observed raw sewage in the street.

Design Details

  • Appropriate Design → Not something that is cutting edge or expensive
  • Proven dehydration technology
  • Ability to be quickly constructed and repaired in-country
  • Target cost: $100

Our Partner: Outreach International

Outreach International is a humanitarian organization that currently works in 14 impoverished countries around the world, assisting hundreds of thousands of children, women and men to overcome the effects of poverty each year.
OI concentrates on long-term investments that bring about sustainable solutions and long-lasting change for the better.

NGO Partner: A Single Drop based in the Philippines and about to expand to Africa.

Cashew Waste

Cashews are one of the favorites of the world’s nuts, but very few people know much about the rest of the story… the tree is closely related to the mango and a cousin of the poison ivy, it produces a fruit which is technically not really a “fruit” but an engorged stem, the “nut” (really a seed) develops outside the fruit, up to 20% of the shell weight is a valuable industrial chemical. The project supporters seek to extract more value for Africa from the cashew crop. Presently raw nuts are shipped abroad for roasting and packaging. These operations could be performed locally, benefitting the communities where the nuts are grown.


A specific goal is to find more uses for by-products – like the fruit and nut shell – so that small farmers can obtain additional income, improving their quality of life.

The Need

The landscape is littered with huge piles of messy shells, while scarce wood resources are consumed to produce energy.

Design Challenges

The oil in the shells (CNSL) is valuable for use in polymers, coatings, and auto brake components it is also noxious (it causes a skin rash much like that from poison ivy) and difficult to extract. Our challenge is to adapt existing technologies to these new circumstances and in a way that is most appropriate for Africa. With or without the oil, the shells have a high energy content, making them suitable for providing process heat for industry or fuel for improved household cooking stoves… except that the simple technologies needed to turn them into charcoal or briquettes don’t exist there yet. When burned in a typical way the oil produces an unacceptable amount of very unpleasant/acrid smoke.

Our Partners

This project is supported by several organizations including the following:

  • Costco
  • African Cashew Initiative
  • The Bill and Melinda Gates Foundationy

Plastic Recycling

The Appropriate Technology Design Team will work with the community in San Juayua/Juan de Dios, El Salvador to utilize discarded waste products, primarily plastic bottles, for non-structural construction materials.


The project aims to design, create, test and deploy a manual recycling system to the community with instructions for local manufacture, operation, and maintenance.

The Need

The community has a shortage of building materials that are effective in insulating the families from common weather conditions. The landscape is littered with plastic soda and water bottles. The community will benefit from both the reduction in the solid waste pollution and by introducing a new source of construction materials to insulate dwellings from rain, wind and heat.



Our Partner: ADESCO

ADESCO is an association formed and regulated by each Municipal government in El Salvador. Each ADESCO works and manages the development of the community in coordination with the local Mayor and his or her office. The specific activities of the San Juan de Dios ADESCO are listed below:

  • Oversee all community and NGO development with a focus on health, water and sanitation projects.
  • Operate, maintain and bill for the community domestic water system that serves approximately 2,000 residents. There are two full-time technicians employed by ADESCO that work on the water system.
  • Interface with EWB and Peace Corps on projects. Recent activities include the construction of 10 new latrines for the most needy families and the design and installation of a new electric pump and the associated infrastructure.
  • Coordinate all activities with the Mayor’s office, including entering into MOU’s, the purchase of materials and the transportation of goods.

To find out more about ATDT projects or to volunteer, e-mail your contact info and
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