William Kamkwamba, a teenager in a Malawi village, built a 12- meter tall windmill using old bicycle parts to provide lighting and power his family fields. See his blog  . This is a typical example of appropriate technology. E.F. Schumacher, author of Small is Beautiful - Economics as if people mattered, founded a group called Practical Action which promotes low-cost, small scale technology that makes a big difference. The group’s website Design for the other 90%  gives descriptive information on how appropriate technology is practiced throughout the world. Afrigadget  is another website dealing in African ingenuity.
 Technological Problems, Sustainable Solutions
Appropriate technology is a grassroots solution to economic needs. Solutions which are appropriate for urban areas may not be so for rural areas where conventional developmental methods, materials and technology may not be appropriate. This calls for a totally new approach in which solutions are found locally.
Appropriate Technology is used to solve technological problems by providing sustainable solutions which are beneficial to the local community. Appropriate technology paves the way for sustainable living and, therefore, works from the bottom up to meet grassroots economic needs, not from the top down. It uses renewable sources of energy and recycles materials wherever possible as it is sensitive to the need to reduce environmental pollution.
 Using Local Skills
Appropriate technology begins with the theory that local people understand local problems better and are thus more equipped to utilize resources to meet their needs. Local people can also prioritize solutions to save precious funding and labor.
Sustainable solutions to technological problems are more effective with the use of local skills and existing knowledge and experience which can be shared by the whole community. This also helps cut down overall costs.
Appropriate technology has the freedom to adopt different real time creative solutions to technological problems. The person who produces a service or a product also becomes the consumer. As a result of this consumer-producers are more likely to care more about their work, making service and goods more reliable and of higher quality.
 Environment Friendly Technology
In appropriate technology the use of renewable energy sources is also encouraged. This significantly benefits the local and global environments as use of renewable sources reduces the emission of carbon dioxide. Carbon dioxide emissions, which occur when oil and coal are burnt, increase the greenhouse effect. This reduction of the emission of sulfur dioxide and nitrous oxides, by not using coal as the primary source of energy, is also beneficial to both local and global environments.
Coal and oil also are not required to be transported over long distances. Food, energy, water, and waste disposal are also handled locally by ecological systems. These are systems that conserve resources by recycling organic nutrients back into the soil and re-using manufactured goods in innovative ways. Thus, appropriate technology makes it possible to satisfy basic human needs while minimizing our impact on the environment.
At Auroville, Pondicherry, India, numerous solar and biogas systems have been integrated into community life. The Centre for Scientific Research (CSR)  was set up there in 1984 to fund and promote research in alternative technology
 Economic Viability for Benefit of Community
Long-term economic viability of appropriate technology is essential for the benefit of the community and to provide suitable employment opportunities. It should be able to provide a number of distinct advantages, such as an improvement in health and safety, education and training, regular employment and income for families. The use of high technology to solve a problem often involves the use of expensive components, which usually need to be imported. This normally requires specialist training, additional costs and time. The need for a supply of spare parts, often expensive, also decreases the likelihood of a sustainable solution to the problem, by increasing the cost of the overall project.
Considering the financial constraints that most developing countries face, the flexibility of appropriate technologies can be used, especially in providing services to the poor.
 Appropriate Technology in Developing Countries
In the past decade, international efforts to increase the coverage of water supply and sanitation for urban residents in developing countries have actively involved community participation. Personnel were trained locally to construct, manage, operate, and maintain service systems and get the public educated about a healthy urban environment. This is an example of culturally and institutionally appropriate technology
Different types of low-cost technologies were developed during the same period which would innovatively use the services of local people and institutions.
 Water Supply and Sanitation
A very wide range of potable water and hygienic sanitation services have been made available. They include full-scale and centralized piped-water and sewage systems with mostly individual house connections, hand pumps and dry or waterborne on-site sewers. The cost of these varies according to the nature of the service.
Contaminated ground water may become a constraint to low-cost water supply options. However, low-cost technologies -- such as hand pumps -- can also be used, even in urban settings. According to a World Bank assessment, "in the areas where groundwater is readily available at moderate depth, constructing a number of wells fitted with hand pumps is by far the cheapest means of providing a good water supply."
 Solid Waste Collection and Disposal
In developing countries, labor is less expensive than in the industrialized countries. Hence, low-cost provision of municipal solid waste services usually involves the use of labor-intensive technology. In developing countries full-scale collection trucks may be replaced with mechanized compact vehicles, and street sweepers, small trucks and hand-pulled or animal-drawn carts.
Costs can sometimes be greatly reduced by private participation through contracting, franchising, competitive bidding, and equipment leasing. In Bangkok (Thailand), contracted municipal solid waste management service appears to have lowered costs. In Seoul (Korea), Jakarta (Indonesia), and Bogota (Colombia), private collections command a substantial cost advantage in labor, wages, and benefits In Kuala Lumpur (Malaysia); private firms make more trips per vehicle per day and collect more waste on each trip, and hence are nearly 50% more productive than the public service. Evidence from Latin American cities also points to lower costs and higher productivity for the private sector.