List of appropriate technology applications

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Appropriate technologies find many applications in building and construction, agriculture, water and sanitation, energy generation and uses, transportation, health care, food preparation and storage, information and communication technologies, as well as finance.

Contents

Building and construction

In order to increase the efficiency of a great number of city services (efficient water provisioning, efficient electricity provisioning, easy traffic flow, water drainage, decreased spread of disease with epidemics, etc.), the city itself must first be built correctly. In the developing world, many cities are expanding rapidly and new ones are being built. Looking into the cities design in advance is a must for every developing nation.

The local context must be considered as, for example, mudbrick may not be durable in a high rainfall area (although a large roof overhang and cement stabilisation can be used to correct for this), and, if the materials are not readily available, the method may be inappropriate. Other forms of natural building may be considered appropriate technology, though in many cases the emphasis is on sustainability and self-sufficiency rather than affordability or suitability. As such, many buildings are also built to function as autonomous buildings (e.g., earthships). One example of an organisation that applies appropriate earthbuilding techniques would be Builders Without Borders.

The building structure must also be considered. Cost-effectiveness is an important issue in projects based around appropriate technology, and one of the most efficient designs herein is the public housing approach. This approach lets everyone have their own Condominium|sleeping/recreation space, yet incorporate communal spaces such as mess halls, latrines, and public showers.

In addition, to decrease costs of operation (heating, cooling, etc.) techniques as Earth sheltering and Trombe walls are often incorporated.

Organizations as Architecture for Humanity also follows principles consistent with appropriate technology, aiming to serve the needs of poor and disaster-affected people.

Chunche, naturally ventilated sheds for drying raisins in Xinjiang Chunche.jpg
Chunche , naturally ventilated sheds for drying raisins in Xinjiang

Agriculture

Appropriate technology has been applied extensively to improve agricultural production in developing countries. In the United States, the National Center for Appropriate Technology operates ATTRA (attra.ncat.org), a national sustainable agriculture assistance program.

The focus of discussion and research regarding technology adoption is the small scale farm, because it accounts for the majority of the planet's agricultural output. [1] The ethical question that emerges in the research is how much to focus on increasing the productivity of a nation's agricultural output and how much to address food insecurity in the population, including among farmers themselves. This issue of framing is significant because if countries are producing enough food for their populations, yet people are still not getting adequate amounts of food or proper nutrition, it is a problem of availability and distribution rather than production. It is possible for countries to have the agricultural capabilities to be completely self-supportive, but still have many food-insecure citizens.  India is an example of this situation. The opposite can also be true; as of 2012, neither Hong Kong nor Singapore had the internal capability to sustainably feed their respective populations, yet they had much better rates of food-security than India. [1] A problem can arise when research focuses solely on advancements in production, ignoring the problem of food-insecurity in these communities.

Food insecurity is more than just a matter of increasing farm production: it is also about farm household income, location, amount of debt, and level of education. [1] Rural and impoverished communities are disproportionately and adversely affected by inequitable distribution of food and resources. [1] Increasing food production and output will not make distributing food easier or more equitable.  Confronting these more difficult issues is the future of the sector's discussions and actions. [1]

Water and sanitation

Water

Hand-operated, reciprocating, positive displacement, water pump in Kosice-Tahanovce, Slovakia (walking beam pump). Pump-tah.jpg
Hand-operated, reciprocating, positive displacement, water pump in Košice-Tahanovce, Slovakia (walking beam pump).

As of 2006, waterborne diseases are estimated to cause 1.8 million deaths each year while about 1.1 billion people lack proper drinking water. [2]

Water generally needs treatment before use, depending on the source and the intended use (with high standards required for drinking water). The quality of water from household connections and community water points in low-income countries is not reliably safe for direct human consumption. Water extracted directly from surface waters and open hand-dug shallow wells nearly always requires treatment.

Appropriate technology options in water treatment include both community-scale and household-scale point-of-use (POU) designs.

The most reliable way to kill microbial pathogenic agents is to heat water to a rolling boil. [3] Other techniques, such as varying forms of filtration, chemical disinfection, and exposure to ultraviolet radiation (including solar UV) have been demonstrated in an array of randomized control trials to significantly reduce levels of waterborne disease among users in low-income countries.

Over the past decade, an increasing number of field-based studies have been undertaken to determine the success of POU measures in reducing waterborne disease. The ability of POU options to reduce disease is a function of both their ability to remove microbial pathogens if properly applied and such social factors as ease of use and cultural appropriateness. Technologies may generate more (or less) health benefit than their lab-based microbial removal performance would suggest.

The current priority of the proponents of POU treatment is to reach large numbers of low-income households on a sustainable basis. Few POU measures have reached significant scale thus far, but efforts to promote and commercially distribute these products to the world's poor have only been under way for a few years.

On the other hand, small-scale water treatment is reaching increasing fractions of the population in low-income countries, particularly in South and Southeast Asia, in the form of water treatment kiosks (also known as water refill stations or packaged water producers). While quality control and quality assurance in such locations may be variable, sophisticated technology (such as multi-stage particle filtration, UV irradiation, ozonation, and membrane filtration) is applied with increasing frequency. Such microenterprises are able to vend water at extremely low prices, with increasing government regulation. Initial assessments of vended water quality are encouraging.

Whether applied at the household or community level, some examples of specific treatment processes include:

Some appropriate technology water supply measures include:

Sanitation

Poor sanitation is a major issue for a large proportion of the human population, with about 2.5 billion people lacking even the most basic forms of sanitation and more than a billion people worldwide practising open defecation in 2015 according to the Joint Monitoring Programme for Water Supply and Sanitation of the United Nations. [5] [6]

The ideas of appropriate technology influenced the provision of sanitation systems for many years. However, since about the early 2000s there has been a departure from a focus on simplistic 'one-size-fits-all' sanitation systems. [7] [8] As conditions vary, sanitation systems also need to vary to meet the needs of the users and other stakeholders. [8]

Technologies for sanitation provision, such as toilets, are important but only one piece of the puzzle. Sanitation needs to be regarded as a system that includes technical and non-technical aspects, such as behavior change and management as well as political aspects – the enabling environment. [9] The overall aim should be to achieve a sustainable sanitation system. One option of achieving that aim can be the ecological sanitation approach which focuses on safe reuse of excreta.

It is impossible to name all possible sanitation technologies that may fall under the category of "appropriate technologies" but some common systems which might be considered to be "appropriate" include:

Energy generation and uses

The term soft energy technology was coined by Amory Lovins to describe "appropriate" renewable energy. [12] "Appropriate" energy technologies are especially suitable for isolated and/or small scale energy needs. Electricity can be provided from:

Some intermediate technologies include:

Finally, urine can also be used as a basis to generate hydrogen (which is an energy carrier). Using urine, hydrogen production is 332% more energy efficient than using water. [16]

Electricity distribution could be improved so to make use of a more structured electricity line arrangement and universal AC power plugs and sockets (e.g., the CEE 7/7 plug). In addition, a universal system of electricity provisioning (e.g., universal voltage, frequency, ampère; e.g., 230 V with 50 Hz), as well as perhaps a better mains power system (e.g., through the use of special systems as perfected single-wire earth returns; e.g., Tunisia's MALT-system, which features low costs and easy placement) [17] [18]

Electricity storage (which is required for autonomous energy systems) can be provided through appropriate technology solutions as deep-cycle and car-batteries (intermediate technology), long duration flywheels, electrochemical capacitors, compressed air energy storage (CAES), liquid nitrogen and pumped hydro. [19] Many solutions for the developing world are sold as a single package, containing a (micro) electricity generation power plant and energy storage. Such packages are called remote-area power supply

LED Lamp with GU10 twist lock fitting, intended to replace halogen reflector lamps. Ampoules.jpg
LED Lamp with GU10 twist lock fitting, intended to replace halogen reflector lamps.

Transportation

A man uses a bicycle to cargo goods in Ouagadougou, Burkina Faso (2007) Person mit fahrrad feb07.jpg
A man uses a bicycle to cargo goods in Ouagadougou, Burkina Faso (2007)

Human powered-vehicles include the bicycle (and the bamboo bicycle), which provides general-purpose transportation at lower costs compared to motorized vehicles, and many advantages over walking, and the whirlwind wheelchair, which provides mobility for disabled people who cannot afford the expensive wheelchairs used in developed countries. Animal powered vehicles/transport may also be another appropriate technology. Certain zero-emissions vehicles may be considered appropriate transportation technology, including light rail, compressed air cars, liquid nitrogen and hydrogen-powered vehicles. Also, vehicles with internal combustion engines may be converted to hydrogen or oxyhydrogen combustion.

Bicycles can also be applied to commercial transport of goods to and from remote areas. An example of this is Karaba, a free-trade coffee co-op in Rwanda, which uses 400 modified bicycles to carry hundreds of pounds of coffee beans for processing. [22] Other projects for developing countries include the redesign of cycle rickshaws to convert them to electric power. [23] [24] However recent reports suggest that these rickshaws are not plying on the roads. [25]

Health care

According to the Global Health Council, rather than the use of professionally schooled doctors, the training of villagers to remedy most maladies in towns in the developing world is most appropriate. [26] Trained villagers are able to eliminate 80% of the health problems. Small (low-cost) hospitals – based on the model of the Jamkhed hospital – can remedy another 15%, while only 5% will need to go to a larger (more expensive) hospital.

Note that many Appropriate Technologies benefit public health, in particular by providing sanitation and safe drinking water. Refrigeration may also provide a health benefit. (These are discussed in the following paragraphs.) This was too found at the Comprehensive Rural Health Project [30] and the Women Health Volunteers projects in countries as Iran, Iraq and Nepal. [31]

Food preparation and storage

Some proven intensive, low-effort food-production systems include urban gardening (indoors and outdoors).[ citation needed ] Indoor cultivation may be set up using hydroponics with Grow lights, while outdoor cultivation may be done using permaculture, forest gardening, no-till farming, Do Nothing Farming, etc. In order to better control the irrigation outdoors, special irrigation systems may be created as well (although this increases costs, and may again open the door to cultivating non-indigenous plants; something which is best avoided).[ citation needed ] One such system for the developing world is discussed here. [32]

Crop production tools are best kept simple (reduces operating difficulty, cost, replacement difficulties and pollution, when compared to motorized equipment). Tools can include scythes, [33] animal-pulled plows [34] (although no-till farming should be preferred), [35] dibbers, wheeled augers [36] [37] (for planting large trees), kirpis, hoes, etc.

Greenhouses are also sometimes included (see Earthship Biotincture).[ citation needed ] Sometimes they are also fitted with irrigation systems, and/or heat sink-systems which can respectively irrigate the plants or help to store energy from the sun and redistribute it at night (when the greenhouse starts to cool down).

According to proponents, Appropriate Technologies can greatly reduce the labor required to prepare food, compared to traditional methods, while being much simpler and cheaper than the processing used in Western countries. This reflects E.F. Schumacher's concept of "intermediate technology," i.e., technology which is significantly more effective and expensive than traditional methods, but still an order of magnitude (10 times) cheaper than developed world technology. Key examples are:

In Ghana, Zouzugu villagers use solar cookers for preparing their meals Solar-Panel-Cooker-in-front-of-hut.jpg
In Ghana, Zouzugu villagers use solar cookers for preparing their meals

Information and communication technologies

Netbooks such as the Asus Eee PC accommodate low-cost information sharing and communication ASUS Eee White Alt.jpg
Netbooks such as the Asus Eee PC accommodate low-cost information sharing and communication

Finance

Through financial systems envisioned especially for the very poor/developed world, many companies have been able to get started with only limited capital. Often banks lend the money to people wishing to start a business (such as with microfinance). In other systems, people for a Rotating Savings and Credit Association or ROSCA to purchase costly material together (such as Tontines and Susu accounts). Organisations, communities, cities or individuals can provide loans to other communities/cities (such as with the approach followed by Kiva, World Vision Microloans, MicroPlace and LETS). Finally, in certain communities (usually isolated communities such as small islands or oases) everything of value is shared. This is called gift economy.

The adopters and implementers of a technology often have less bargaining and social power than those who design and provide the technology. In stakeholder negotiations and relationships, the uneven distribution of power often stems from the lack of access to capital. In the case of small-holder farming communities, for example, farmers struggle to access initial capital, and so outside investors have significantly more bargaining power. [45] This dynamic gives power to outside investors over farmers, technology adopters, and local community members. A local community's best interest might not always be considered by outside investing forces.

Related Research Articles

<span class="mw-page-title-main">Energy storage</span> Captured energy for later usage

Energy storage is the capture of energy produced at one time for use at a later time to reduce imbalances between energy demand and energy production. A device that stores energy is generally called an accumulator or battery. Energy comes in multiple forms including radiation, chemical, gravitational potential, electrical potential, electricity, elevated temperature, latent heat and kinetic. Energy storage involves converting energy from forms that are difficult to store to more conveniently or economically storable forms.

<span class="mw-page-title-main">Solar energy</span> Radiant light and heat from the Sun, harnessed with technology

Solar energy is the radiant energy from the Sun's light and heat, which can be harnessed using a range of technologies such as solar electricity, solar thermal energy and solar architecture. It is an essential source of renewable energy, and its technologies are broadly characterized as either passive solar or active solar depending on how they capture and distribute solar energy or convert it into solar power. Active solar techniques include the use of photovoltaic systems, concentrated solar power, and solar water heating to harness the energy. Passive solar techniques include designing a building for better daylighting, selecting materials with favorable thermal mass or light-dispersing properties, and organize spaces that naturally circulate air.

<span class="mw-page-title-main">Solar thermal energy</span> Technology using sunlight for heat

Solar thermal energy (STE) is a form of energy and a technology for harnessing solar energy to generate thermal energy for use in industry, and in the residential and commercial sectors. Solar thermal collectors are classified by the United States Energy Information Administration as low-, medium-, or high-temperature collectors. Low-temperature collectors are generally unglazed and used to heat swimming pools or to heat ventilation air. Medium-temperature collectors are also usually flat plates but are used for heating water or air for residential and commercial use.

<span class="mw-page-title-main">Solar water heating</span> Use of sunlight for water heating with a solar thermal collector

Solar water heating (SWH) is heating water by sunlight, using a solar thermal collector. A variety of configurations are available at varying cost to provide solutions in different climates and latitudes. SWHs are widely used for residential and some industrial applications.

Electrification is the process of powering by electricity and, in many contexts, the introduction of such power by changing over from an earlier power source. In the context of history of technology and economic development, electrification refers to the build-out of the electricity generation and electric power distribution systems. In the context of sustainable energy, electrification refers to the build-out of super grids with energy storage to accommodate the energy transition to renewable energy and the switch of end-uses to electricity.

<span class="mw-page-title-main">Environmental technology</span> Technical and technological processes for protection of the environment

Environmental technology (envirotech) is the use of engineering and technological approaches to understand and address issues that affect the environment with the aim of fostering environmental improvement. It involves the application of science and technology in the process of addressing environmental challenges through environmental conservation and the mitigation of human impact to the environment.

<span class="mw-page-title-main">Grid energy storage</span> Large scale electricity supply management

Grid energy storage is a collection of methods used for energy storage on a large scale within an electrical power grid. Electrical energy is stored during times when electricity is plentiful and inexpensive or when demand is low, and later returned to the grid when demand is high, and electricity prices tend to be higher.

<span class="mw-page-title-main">Rural electrification</span> Bringing electrical power to rural areas

Rural electrification is the process of bringing electrical power to rural and remote areas. Rural communities are suffering from colossal market failures as the national grids fall short of their demand for electricity. As of 2019, 770 million people live without access to electricity – 10.2% of the global population. Electrification typically begins in cities and towns and gradually extends to rural areas, however, this process often runs into obstacles in developing nations. Expanding the national grid is expensive and countries consistently lack the capital to grow their current infrastructure. Additionally, amortizing capital costs to reduce the unit cost of each hook-up is harder to do in lightly populated areas. If countries are able to overcome these obstacles and reach nationwide electrification, rural communities will be able to reap considerable amounts of economic and social development.

<span class="mw-page-title-main">Off-the-grid</span> Not being connected to public utilities

Off-the-grid or off-grid is a characteristic of buildings and a lifestyle designed in an independent manner without reliance on one or more public utilities. The term "off-the-grid" traditionally refers to not being connected to the electrical grid, but can also include other utilities like water, gas, and sewer systems, and can scale from residential homes to small communities. Off-the-grid living allows for buildings and people to be self-sufficient, which is advantageous in isolated locations where normal utilities cannot reach and is attractive to those who want to reduce environmental impact and cost of living. Generally, an off-grid building must be able to supply energy and potable water for itself, as well as manage food, waste and wastewater.

<span class="mw-page-title-main">Microgeneration</span> Small-scale heating and electric power creation

Microgeneration is the small-scale production of heat or electric power from a "low carbon source," as an alternative or supplement to traditional centralized grid-connected power.

Solar air conditioning, or "solar-powered air conditioning", refers to any air conditioning (cooling) system that uses solar power.

<span class="mw-page-title-main">Hybrid power</span> Combinations between different technologies to generate electric power

Hybrid power are combinations between different technologies to produce power.

<span class="mw-page-title-main">Renewable energy in Africa</span>

The developing nations of Africa are popular locations for the application of renewable energy technology. Currently, many nations already have small-scale solar, wind, and geothermal devices in operation providing energy to urban and rural populations. These types of energy production are especially useful in remote locations because of the excessive cost of transporting electricity from large-scale power plants. The applications of renewable energy technology has the potential to alleviate many of the problems that face Africans every day, especially if done in a sustainable manner that prioritizes human rights.

<span class="mw-page-title-main">Organic Rankine cycle</span> Variation on the Rankine thermodynamic cycle

In thermal engineering, the organic Rankine cycle (ORC) is a type of thermodynamic cycle. It is a variation of the Rankine cycle named for its use of an organic, high-molecular-mass fluid whose vaporization temperature is lower than that of water. The fluid allows heat recovery from lower-temperature sources such as biomass combustion, industrial waste heat, geothermal heat, solar ponds etc. The low-temperature heat is converted into useful work, that can itself be converted into electricity.

<span class="mw-page-title-main">Photovoltaic thermal hybrid solar collector</span>

Photovoltaic thermal collectors, typically abbreviated as PVT collectors and also known as hybrid solar collectors, photovoltaic thermal solar collectors, PV/T collectors or solar cogeneration systems, are power generation technologies that convert solar radiation into usable thermal and electrical energy. PVT collectors combine photovoltaic solar cells, which convert sunlight into electricity, with a solar thermal collector, which transfers the otherwise unused waste heat from the PV module to a heat transfer fluid. By combining electricity and heat generation within the same component, these technologies can reach a higher overall efficiency than solar photovoltaic (PV) or solar thermal (T) alone.

Zero-carbon housing is housing that does not emit greenhouse gasses (GHGs) into the atmosphere, either directly, or indirectly due to consumption electricity produced using fossil fuels. Most commonly zero-carbon housing is taken to mean zero emissions of carbon dioxide, which is the main climate pollutant from homes, although fugitive methane may also be emitted from natural gas pipes and appliances.

The Appropriate Technology Collaborative is an American non-profit dedicated to designing everyday technologies for the global poor.

<span class="mw-page-title-main">Solar-powered Stirling engine</span> Technology used in concentrated solar power stations

A solar powered Stirling engine is a heat engine powered by a temperature gradient generated by the sun. Even though Stirling engines can run with a small temperature gradient, it is more efficient to use concentrated solar power.

<span class="mw-page-title-main">Fecal sludge management</span> Collection, transport, and treatment of fecal sludge from onsite sanitation systems

Fecal sludge management (FSM) is the storage, collection, transport, treatment and safe end use or disposal of fecal sludge. Together, the collection, transport, treatment and end use of fecal sludge constitute the "value chain" or "service chain" of fecal sludge management. Fecal sludge is defined very broadly as what accumulates in onsite sanitation systems and specifically is not transported through a sewer. It is composed of human excreta, but also anything else that may go into an onsite containment technology, such as flushwater, cleansing materials, menstrual hygiene products, grey water, and solid waste. Fecal sludge that is removed from septic tanks is called septage.

There are many practical applications for solar panels or photovoltaics. From the fields of the agricultural industry as a power source for irrigation to its usage in remote health care facilities to refrigerate medical supplies. Other applications include power generation at various scales and attempts to integrate them into homes and public infrastructure. PV modules are used in photovoltaic systems and include a large variety of electrical devices.

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