Axel Heinemann: 1 revision

2014-11-08T16:51:39Z

1 revision

Franz Schreier at 18:08, 6 November 2014

2014-11-06T18:08:35Z

New page

{{Powering Agriculture Technology Database
|PAT quality check=Yes
|PAT Name=Coolers
|PAT Picture=Cooler.jpg
|PAT Type RE=Renewable Energy
|PAT Description=An evaporative cooler (also swamp cooler, desert cooler and wet air cooler) is a device that cools air through the evaporation of water. Evaporative cooling differs from typical air conditioning systems which use vapor-compression or absorption refrigeration cycles. Evaporative cooling works by employing water's large enthalpy of vaporization. The temperature of dry air can be dropped significantly through the phase transition of liquid water to water vapor (evaporation), which can cool air using much less energy than refrigeration. In extremely dry climates, evaporative cooling of air has the added benefit of conditioning the air with more moisture for the comfort of building occupants.
(Source: http://en.wikipedia.org/wiki/Evaporative_cooler

Much of the post-harvest loss of fruits and vegetables in developing countries is due to the lack of proper storage facilities. While refrigerated cool stores are the best method of preserving fruits and vegetables they are expensive to buy and run. Consequently, in
developing countries there is an interest in simple low-cost alternatives, many of which depend on evaporative cooling which is simple and does not require any external power supply.

The basic principle relies on cooling by evaporation. When water vaporates it draws energy from its surroundings which produces a considerable cooling effect. Evaporative cooling occurs when air, that is not too humid, passes over a wet surface; the faster the rate of
evaporation the greater the cooling. The efficiency of an evaporative cooler depends on the humidity of the surrounding air. Very dry air can absorb a lot of moisture so greater cooling occurs. In the extreme case of air that is totally saturated with water, no evaporation can take
place and no cooling occurs.

Generally, an evaporative cooler is made of a porous material that is fed with water. Hot dry air is drawn over the material. The water evaporates into the air raising its humidity and at the same time reducing the temperature of the air. There are many different styles of evaporative
coolers. The design will depend on the materials available and the users requirements. Some examples of evaporative cooling designs are described below. (Source: https://practicalaction.org/evaporative-cooling-1)
|PAT Technology Application Other=Evaporation of water
|PAT Actions Cooling=Cooling
|PAT Dev Region Worldwide=Worldwide
|PAT Dev Region South Asia=
|PAT Dev Country South Asia=
|PAT Dev Region Africa=
|PAT Dev Country Africa=
|PAT Dev Region East Asia=
|PAT Dev Country East Asia=
|PAT Dev Region Europe=
|PAT Dev Country Europe=
|PAT Dev Region Latin America=
|PAT Dev Country Latin America=
|PAT Dev Region Middle East=
|PAT Dev Country Middle East=
|PAT Dev Region North America=
|PAT Dev Country North America=
|PAT Dep Region Worldwide=Worldwide
|PAT Dep Region South Asia=
|PAT Dep Country South Asia=
|PAT Dep Region Africa=
|PAT Dep Country Africa=
|PAT Dep Region East Asia=
|PAT Dep Country East Asia=
|PAT Dep Region Europe=
|PAT Dep Country Europe=
|PAT Dep Region Latin America=
|PAT Dep Country Latin America=
|PAT Dep Region Middle East=
|PAT Dep Country Middle East=
|PAT Dep Region North America=
|PAT Dep Country North America=
|PAT Dep Pot Region Worldwide=Worldwide
|PAT Dep Pot Region South Asia=
|PAT Dep Pot Country South Asia=
|PAT Dep Pot Region Africa=
|PAT Dep Pot Country Africa=
|PAT Dep Pot Region East Asia=
|PAT Dep Pot Country East Asia=
|PAT Dep Pot Region Europe=
|PAT Dep Pot Country Europe=
|PAT Dep Pot Region Latin America=
|PAT Dep Pot Country Latin America=
|PAT Dep Pot Region Middle East=
|PAT Dep Pot Country Middle East=
|PAT Dep Pot Region North America=
|PAT Dep Pot Country North America=
|PAT Economics=Low cost coolig with physical limits;
|PAT Technology Development Level=Widespread use but the evaporative cooling did not tap its potential yet;
|PAT Maintenance=Low: Technology to be maintained through its life cycle requires less common tools and/or training is required for maintenance;
|PAT Infrastructure=Low: Technology can be developed with less common tools, low development level supporting technologies and moderately trained personnel;
|PAT Required Resources Manufacture=Metals, plastics;
|PAT Required Resources Operation=Water, cooling pads (cardboard, plastics, aluminum or natural fibre materials);
|PAT Deployment Level=Worldwide use;
|PAT Deployment Capability=The technology can be widely deployed limited only by education;
|PAT Requirements for Deployment=Know-how and technology transfer as well as trainings;
|PAT Relevance Autonomy=Independent: Fully autonomous and self-supporting, when water is availble;
|PAT Environment Impacts=Zero: no direct or indirect emissions;
|PAT Bio-Cybernetic=Yes;
|PAT Links=http://en.wikipedia.org/wiki/Evaporative_cooler

https://practicalaction.org/clay-evaporative-cooler-performance-research

https://practicalaction.org/evaporative-cooling-1

https://practicalaction.org/refrigeration-in-developing-countries-1
|PAT Category=Cooling
|PAT Pumping=
|PAT Lighting=
|PAT Heating=
|PAT Cooling=Free Cooling
|PAT Wind=
|PAT Biomass=
|PAT Biofuel=
|PAT Biogas=
|PAT Humans=
|PAT Animals=
|PAT Biochar=
|PAT Composte=
|PAT Insects=
|PAT Plants=
|PAT Others=
}}

Coolers (PA Technology) - Revision history

Axel Heinemann: 1 revision

Franz Schreier at 18:08, 6 November 2014