Solar Drying - Revision history

Ranisha: /* Solar Dryers */

2022-06-14T13:03:43Z

Solar Dryers

Ranisha: /* Open-Drying */

2022-06-14T13:03:17Z

Open-Drying

Ranisha: /* Choosing a Right Dryer */

2022-06-14T13:01:43Z

Choosing a Right Dryer

Show changes

Ranisha: /* Open-Drying */

2022-06-14T12:47:10Z

Open-Drying

Ranisha at 12:41, 14 June 2022

2022-06-14T12:41:50Z

Ranisha: /* Open-drying */

2022-06-14T12:41:33Z

Open-drying

Ranisha at 09:59, 14 June 2022

2022-06-14T09:59:54Z

Show changes

Rebecca Navarro: /* Coffee processing with solar dryers in Peru */

2019-06-17T09:57:21Z

Coffee processing with solar dryers in Peru

Rebecca Navarro: /* Solar Dryers */

2019-06-17T08:46:49Z

Solar Dryers

Rebecca Navarro: /* Solar Dryers */

2019-06-17T08:45:56Z

Solar Dryers

← Older revision		Revision as of 13:03, 14 June 2022
Line 30:		Line 30:
	The '''Hohenheim ‖-type solar tunnel''' dryer combines simple construction, use of renewable energy and easy handling. The model is equipped with a photovoltaic (PV) driving fan with a power requirement of 20-40 W. The thermal energy gained from solar radiation is up to 60 kWh/day (equivalent to 15 kg of firewood). As a cooperative development between the Institute for Agricultural Engineering in the Tropics and Subtropics of Hohenheim University and INNOTECH Engineering Ltd., solar tunnel dryers are in commercial operation in more than 60 countries all over the world.<ref>GIZ-HERA (2011): Modern Energy Services for Modern Agriculture - A Review of Smallholder Farming in Developing Countries.</ref>There is a guidance paper on how to install a solar tunnel dryer with explanations and pictures, available at: http://www.ats.uni-hohenheim.de/_deutsche_site/projekte/_pdf/Guidance.pdf.		The '''Hohenheim ‖-type solar tunnel''' dryer combines simple construction, use of renewable energy and easy handling. The model is equipped with a photovoltaic (PV) driving fan with a power requirement of 20-40 W. The thermal energy gained from solar radiation is up to 60 kWh/day (equivalent to 15 kg of firewood). As a cooperative development between the Institute for Agricultural Engineering in the Tropics and Subtropics of Hohenheim University and INNOTECH Engineering Ltd., solar tunnel dryers are in commercial operation in more than 60 countries all over the world.<ref>GIZ-HERA (2011): Modern Energy Services for Modern Agriculture - A Review of Smallholder Farming in Developing Countries.</ref>There is a guidance paper on how to install a solar tunnel dryer with explanations and pictures, available at: http://www.ats.uni-hohenheim.de/_deutsche_site/projekte/_pdf/Guidance.pdf.

−	A simple overview about '''different types of solar dryers''' can be found [https://gc21.giz.de/ibt/var/app/wp385P/2624/wp-content/uploads/2015/03/PAEGC_MOOC_COMPILED_READER.pdf#page=54 here].	+	A simple overview about '''different types of solar dryers''' can be found [https://gc21.giz.de/ibt/var/app/wp385P/2624/wp-content/uploads/2015/03/PAEGC_MOOC_COMPILED_READER.pdf#page=54 here]. Also see: [[Sustainable Energy for Drying]].

@@ Line 12: / Line 12: @@
 =Open-Drying =
-'''Open-air drying''' takes place when food is exposed to the sun and wind by placing it in trays, on racks, or on the ground. The advantage of drying products directly open-air is that almost no costs for fuel and appliances have to be spent by the farmer. However, the dried products are often of lower quality due to varying temperature levels and contamination of the products with dust, vermin’s and leafs. <ref name="Häuser">Häuser</ref>  Up to 70 per cent of agricultural products spoil during the traditional process of open-air drying, especially in tropical and subtropical regions<ref name="http://www.innotech-ing.de/Innotech/english/Processing.html">http://www.innotech-ing.de/Innotech/english/Processing.html</ref>.  Open-drying is also limited to certain times of the day when the sun is shining and is mostly suitable for locations where the humidity is below 60%.<ref>Ahmed et al., “Different Drying Methods.”</ref> Open drying is popular for drying grains like rice, wheat in many Asian and African countries. For more information about open drying see [http://www.knowledgebank.irri.org/step-by-step-production/postharvest/drying/traditional-drying-systems/sun-drying here].
+'''Open-air drying''' takes place when food is exposed to the sun and wind by placing it in trays, on racks, or on the ground. The advantage of drying products directly open-air is that almost no costs for fuel and appliances have to be spent by the farmer. However, the dried products are often of lower quality due to varying temperature levels and contamination of the products with dust, vermin’s and leafs.<ref>Häuser, M./ Ankila, O. (1997): Solar Drying in Morocco - Experience with Solar Drying in Marocco from the GTZ Special Energy Programme (SEP); Overview on technologies, drying techniques, and economics.</ref> Up to 70 per cent of agricultural products spoil during the traditional process of open-air drying, especially in tropical and subtropical regions<ref name="http://www.innotech-ing.de/Innotech/english/Processing.html">http://www.innotech-ing.de/Innotech/english/Processing.html</ref>.  Open-drying is also limited to certain times of the day when the sun is shining and is mostly suitable for locations where the humidity is below 60%.<ref>Ahmed et al., “Different Drying Methods.”</ref> Open drying is popular for drying grains like rice, wheat in many Asian and African countries. For more information about open drying see [http://www.knowledgebank.irri.org/step-by-step-production/postharvest/drying/traditional-drying-systems/sun-drying here].
 =Solar Dryers  =

@@ Line 12: / Line 12: @@
 =Open-Drying =
-'''Open-air or unimproved drying''' takes place when food is exposed to the sun and wind by placing it in trays, on racks, or on the ground. The advantage of drying products directly open-air is that almost no costs for fuel and appliances have to be spent by the farmer. However, the dried products are often of lower quality due to varying temperature levels and contamination of the products with dust, vermin’s and leafs. <ref name="Häuser">Häuser</ref>  Up to 70 per cent of agricultural products spoil during the traditional process of open-air drying, especially in tropical and subtropical regions<ref name="http://www.innotech-ing.de/Innotech/english/Processing.html">http://www.innotech-ing.de/Innotech/english/Processing.html</ref>.  Open-drying is also limited to certain times of the day when the sun is shining and is mostly suitable for locations where the humidity is below 60%.<ref>Ahmed et al., “Different Drying Methods.”</ref>
+'''Open-air drying''' takes place when food is exposed to the sun and wind by placing it in trays, on racks, or on the ground. The advantage of drying products directly open-air is that almost no costs for fuel and appliances have to be spent by the farmer. However, the dried products are often of lower quality due to varying temperature levels and contamination of the products with dust, vermin’s and leafs. <ref name="Häuser">Häuser</ref>  Up to 70 per cent of agricultural products spoil during the traditional process of open-air drying, especially in tropical and subtropical regions<ref name="http://www.innotech-ing.de/Innotech/english/Processing.html">http://www.innotech-ing.de/Innotech/english/Processing.html</ref>.  Open-drying is also limited to certain times of the day when the sun is shining and is mostly suitable for locations where the humidity is below 60%.<ref>Ahmed et al., “Different Drying Methods.”</ref>
 =Solar Dryers  =

@@ Line 11: / Line 11: @@
 Agricultural products can be dried open-air directly in the sun or with dryers powered by biomass or solar energy.  This article outlines the different drying methods:
-== Open-Drying ==
+=Open-Drying =
 '''Open-air or unimproved drying''' takes place when food is exposed to the sun and wind by placing it in trays, on racks, or on the ground. The advantage of drying products directly open-air is that almost no costs for fuel and appliances have to be spent by the farmer. However, the dried products are often of lower quality due to varying temperature levels and contamination of the products with dust, vermin’s and leafs. <ref name="Häuser">Häuser</ref>  Up to 70 per cent of agricultural products spoil during the traditional process of open-air drying, especially in tropical and subtropical regions<ref name="http://www.innotech-ing.de/Innotech/english/Processing.html">http://www.innotech-ing.de/Innotech/english/Processing.html</ref>.  Open-drying is also limited to certain times of the day when the sun is shining and is mostly suitable for locations where the humidity is below 60%.<ref>Ahmed et al., “Different Drying Methods.”</ref>

@@ Line 11: / Line 11: @@
 Agricultural products can be dried open-air directly in the sun or with dryers powered by biomass or solar energy.  This article outlines the different drying methods:
-=== Open-drying ===
+== Open-Drying ==
 '''Open-air or unimproved drying''' takes place when food is exposed to the sun and wind by placing it in trays, on racks, or on the ground. The advantage of drying products directly open-air is that almost no costs for fuel and appliances have to be spent by the farmer. However, the dried products are often of lower quality due to varying temperature levels and contamination of the products with dust, vermin’s and leafs. <ref name="Häuser">Häuser</ref>  Up to 70 per cent of agricultural products spoil during the traditional process of open-air drying, especially in tropical and subtropical regions<ref name="http://www.innotech-ing.de/Innotech/english/Processing.html">http://www.innotech-ing.de/Innotech/english/Processing.html</ref>.  Open-drying is also limited to certain times of the day when the sun is shining and is mostly suitable for locations where the humidity is below 60%.<ref>Ahmed et al., “Different Drying Methods.”</ref>

@@ Line 52: / Line 52: @@
 = Project examples =
 == Coffee processing with solar dryers in Peru<br/> ==
-<span lang="en-gb">Energising Development Peru promotes solar dryers among individual smallholder coffee farmers for the first drying period,during which the humidity of the beans is reduced to around 25 per cent. The solar dryer improves the drying process by filtering UV radiation, concentrating heat, reducing the relative humidity of the air and thus drying the beans with constant and natural ventilation. However, coffee can only be stored and exported at a lower level of humidity. A second drying phase is therefore required, that reduces the humidity of the beans to around 12 per cent; this phase takes place in a bigger solar dryer with a capacity for up to 2 tonnes of coffee, which is managed by farmers’ associations. Victoria Esteban Fuentes has a farm of two hectares in Santa Anita, Satipo, Peru. Before the adoption of the new solar dryer, approximately 70 per cent of Victoria’s coffee harvest met export standards. The solar dryer has increased this rate by eight per cent. Victoria’s income has therefore increased by PEN 2,400 (USD 885) or 30 per cent per annum. The investment in an efficient solar dryer certainly paid off for her. Please find further information at [http://www.produse.org/imglib/downloads/energy_sources/PRODUSE-Factsheet-Peru.pdf http://www.produse.org/imglib/downloads/energy_sources/PRODUSE-Factsheet-Peru.pdf]</span><br/>
+<span lang="en-gb">Energising Development Peru promotes solar dryers among individual smallholder coffee farmers for the first drying period, during which the humidity of the beans is reduced to around 25 per cent. The solar dryer improves the drying process by filtering UV radiation, concentrating heat, reducing the relative humidity of the air and thus drying the beans with constant and natural ventilation. However, coffee can only be stored and exported at a lower level of humidity. A second drying phase is therefore required, that reduces the humidity of the beans to around 12 per cent; this phase takes place in a bigger solar dryer with a capacity for up to 2 tonnes of coffee, which is managed by farmers’ associations. Victoria Esteban Fuentes has a farm of two hectares in Santa Anita, Satipo, Peru. Before the adoption of the new solar dryer, approximately 70 per cent of Victoria’s coffee harvest met export standards. The solar dryer has increased this rate by eight per cent. Victoria’s income has therefore increased by PEN 2,400 (USD 885) or 30 per cent per annum. The investment in an efficient solar dryer certainly paid off for her. Please find further information at [http://www.produse.org/imglib/downloads/energy_sources/PRODUSE-Factsheet-Peru.pdf http://www.produse.org/imglib/downloads/energy_sources/PRODUSE-Factsheet-Peru.pdf]</span><br/>
 [[File:GIZ Peru Quiroz Solar drying inside.jpg|thumb|left|350px|Drying within a solar dryer protects the yield against spoiling by rain or wind and animals (Source: J. C. Quiroz, GIZ EnDev Peru).]]
@@ Line 62: / Line 63: @@
 <br/>
 == <br/>Drying peaches with solar dryers in Bolivia<br/> ==

@@ Line 20: / Line 20: @@
 <br/>
@@ Line 32: / Line 33: @@
 A simple overview about '''different types of solar dryers''' can be found [https://gc21.giz.de/ibt/var/app/wp385P/2624/wp-content/uploads/2015/03/PAEGC_MOOC_COMPILED_READER.pdf#page=54 here].<br/>
-The '''Hohenheim‖-type solar tunnel''' dryer combines simple construction, use of renewable energy and easy handling. The model is equipped with a photovoltaic (PV) driving fan with a power requirement of 20-40 W. The thermal energy gained from solar radiation is up to 60 kWh/day (equivalent to 15 kg of firewood). As a cooperative development between the Institute for Agricultural Engineering in the Tropics and Subtropics of Hohenheim University and INNOTECH Engineering Ltd., solar tunnel dryers are in commercial operation in more than 60 countries all over the world.<ref>GIZ-HERA (2011): Modern Energy Services for Modern Agriculture - A Review of Smallholder Farming in Developing Countries.</ref>There is a guidance paper on how to install a solar tunnel dryer with explanations and pictures, available at: [http://www.ats.uni-hohenheim.de/_deutsche_site/projekte/_pdf/Guidance.pdf http://www.ats.uni-hohenheim.de/_deutsche_site/projekte/_pdf/Guidance.pdf].<br/>
+The '''Hohenheim ‖-type solar tunnel''' dryer combines simple construction, use of renewable energy and easy handling. The model is equipped with a photovoltaic (PV) driving fan with a power requirement of 20-40 W. The thermal energy gained from solar radiation is up to 60 kWh/day (equivalent to 15 kg of firewood). As a cooperative development between the Institute for Agricultural Engineering in the Tropics and Subtropics of Hohenheim University and INNOTECH Engineering Ltd., solar tunnel dryers are in commercial operation in more than 60 countries all over the world.<ref>GIZ-HERA (2011): Modern Energy Services for Modern Agriculture - A Review of Smallholder Farming in Developing Countries.</ref>There is a guidance paper on how to install a solar tunnel dryer with explanations and pictures, available at: [http://www.ats.uni-hohenheim.de/_deutsche_site/projekte/_pdf/Guidance.pdf http://www.ats.uni-hohenheim.de/_deutsche_site/projekte/_pdf/Guidance.pdf].<br/>
 <br/>

@@ Line 20: / Line 20: @@
 <br/>
 = Solar Dryers<br/> =
@@ Line 28: / Line 29: @@
 [[File:GIZ Pereyra Bolivia Solar drying.JPG|thumb|left|400px|Solar drying in Bolivia (Source: N. Pereya, GIZ EnDev Bolivia).]] There are different types of solar dryers, such as direct drying (solar box dryer), indirect drying (solar cabinet dryer), mixed mode drying (solar tunnel dryer) or hybrid drying (hybrid solar/biomass cabinet dryer). Small-scale solar box and cabinet dryers are based on natural air convection, while solar tunnel dryer is based on forced convection (air circulation fan necessary).<br/>
 A simple overview about '''different types of solar dryers''' can be found [https://gc21.giz.de/ibt/var/app/wp385P/2624/wp-content/uploads/2015/03/PAEGC_MOOC_COMPILED_READER.pdf#page=54 here].<br/>
@@ Line 41: / Line 40: @@
 *Axtell, Barrie/ Swetman, Tony (2002): [https://practicalaction.org/small-scale-drying-technologies Small-scale Drying Technologies], Published by Practical Action. This Technical Brief describes improved drying systems that suitable for use by small-scale producers.
 *Häuser, M./ Ankila, O. (1997): Solar Drying in Morocco - Experience with Solar Drying in Marocco from the GTZ Special Energy Programme (SEP); Overview on technologies, drying techniques, and economics.
-*Green, Matthew G./ Schwarz, Dishna (2001): [[:File:Green_Schwarz_(2001)_Solar_Drier_Plans_PGCP_Coconut_Drier_and_Kenya_Black_Box_Drier.pdf|Solar Drier Plans: PGCP Coconut Drier and Kenya Black Box Drier; GTZ-GATE. 2001]]
+*Green, Matthew G./ Schwarz, Dishna (2001): [[:File:Green Schwarz (2001) Solar Drier Plans PGCP Coconut Drier and Kenya Black Box Drier.pdf|Solar Drier Plans: PGCP Coconut Drier and Kenya Black Box Drier; GTZ-GATE. 2001]]
-*Green, Matthew G./ Schwarz, Dishna (2001): [[:File:Green_Schwarz_(2001)_Solar_Drying_Technology_for_Food_Preservation.pdf|Solar Drying Technology for Food Preservation; GTZ-GATE 2001]]. This publication presents possibilities of solar drying with a focus on technical needs, classification of driers and selection criteria´s. Moreover the publication provides information on moisture content of foods, drier components, the drying process, and the capabilities of solar driers.
+*Green, Matthew G./ Schwarz, Dishna (2001): [[:File:Green Schwarz (2001) Solar Drying Technology for Food Preservation.pdf|Solar Drying Technology for Food Preservation; GTZ-GATE 2001]]. This publication presents possibilities of solar drying with a focus on technical needs, classification of driers and selection criteria´s. Moreover the publication provides information on moisture content of foods, drier components, the drying process, and the capabilities of solar driers.
-*Green, Matthew G./ Schwarz, Dishna (2001): [[:File:Greeen_Schwarz_(2001)_Solar_Drying_Equipment_Notes_on_Three_Driers.pdf|Solar Drying Equipment GATE 2001]]; GTZ-GATE.
+*Green, Matthew G./ Schwarz, Dishna (2001): [[:File:Greeen Schwarz (2001) Solar Drying Equipment Notes on Three Driers.pdf|Solar Drying Equipment GATE 2001]]; GTZ-GATE.
 *Swetman, Tony (2012): [https://practicalaction.org/solar-drying-séchage-solaire Séchage Solaire], published by Practical Action. La chaleur du soleil, associée au vent, est utilisée pour sécher les cultures vivrières, dans le but de leur conservation, depuis des milliers d'années.
 *Noble, Neil (2002): [https://practicalaction.org/a-simple-solar-dryer A Simple Solar Dryer], published by Practical Action. This dryer is a mud brick construction built close to the ground using low-cost materials for all its parts.
@@ Line 49: / Line 48: @@
 <br/>
 = Project examples =