Construction manual and 3D-model : SolarFood Indirect solar dryer, generation 2
(2026)- Abstract
- This is a construction manual for the latest SolarFood indirect solar dryer at the time of publication. It is intended as a practical guide for carpenters, and assumes a basic level of carpentry experience.
A Blender 3D model is also included alongside the manual.
Further information
The standard capacity of the dryer is around 5-10 kg depending on the crop, but can be scaled up or down as needed by adjusting the dryer dimensions. The dryer itself is an indirect solar dryer, developed and field-tested together with farmers in Bhutan and Nepal over multiple development cycles.
While this manual describes the construction process when using wood as the main body material, the same design can be used... (More) - This is a construction manual for the latest SolarFood indirect solar dryer at the time of publication. It is intended as a practical guide for carpenters, and assumes a basic level of carpentry experience.
A Blender 3D model is also included alongside the manual.
Further information
The standard capacity of the dryer is around 5-10 kg depending on the crop, but can be scaled up or down as needed by adjusting the dryer dimensions. The dryer itself is an indirect solar dryer, developed and field-tested together with farmers in Bhutan and Nepal over multiple development cycles.
While this manual describes the construction process when using wood as the main body material, the same design can be used for steel-based solar dryers as well. Builders are encouraged to apply their own judgement, and explore different ways of adapting or improving the design as needed to suit local conditions and material availability.
Please note that this manual is provided as-is for informational purposes. SolarFood is not liable for any injury, damage or loss resulting from construction, transportation or use of dryers built using this manual. Dryer performance will also vary depending on factors such as materials used, workmanship, climate conditions and drying load.
This manual is distributed under a CC-BY license. Anyone is free to distribute, remix, adapt, and build upon this manual, as long as attribution is given to SolarFood.
Background
The SolarFood project is an international developmental research collaboration led by Lund University and Ruralis. The aim of the project is to reduce post-harvest losses in Bhutan and Nepal through the development of efficient, affordable and locally adapted solar dryers. The project has been running since 2021, funded by the Swedish Research Council (VR-2020-04071) during 2021-2025, and the Research Council of Norway (project number 352437) during 2026-2028.
As mentioned, the solar dryer design described in this manual is the result of multiple iterative development cycles carried out in close collaboration with local farmers, carpenters and research partners, including Kathmandu University (KU) in Nepal and Jigme Namgyel Engineering College (JNEC) in Bhutan. Both steel and wooden versions exist. The wooden version is cheaper and easier to construct, and is suitable in non-rainy weather, while the steel version is more suitable for wet climates.
Unlike many other dryers on the market, the indirect solar dryers developed within SolarFood utilise a cheap heat exchanger to recycle heat from the hot, moist air before it leaves the dryer. This significantly increases efficiency of the dryers with only a minor cost increase. The fans are the only components requiring external power, and they draw only a few W in total, which keeps the running costs low.
In case of questions, suggestions for improvement or other input, we would be happy to hear from you. Please contact Professor Martin Andersson at martin.andersson@energy.lth.se. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/e35abdd5-80bc-463d-838a-484f627dbac3
- author
- Andreasson, Noah LU
- contributor
- Andersson, Martin
LU
- organization
- publishing date
- 2026
- type
- Book/Report
- publication status
- published
- subject
- publisher
- Lund University
- DOI
- 10.5281/zenodo.20401617
- language
- English
- LU publication?
- yes
- id
- e35abdd5-80bc-463d-838a-484f627dbac3
- date added to LUP
- 2026-05-26 22:39:13
- date last changed
- 2026-09-16 13:14:33
@techreport{e35abdd5-80bc-463d-838a-484f627dbac3,
abstract = {{This is a construction manual for the latest SolarFood indirect solar dryer at the time of publication. It is intended as a practical guide for carpenters, and assumes a basic level of carpentry experience.<br/><br/>A Blender 3D model is also included alongside the manual.<br/><br/><br/>Further information<br/><br/>The standard capacity of the dryer is around 5-10 kg depending on the crop, but can be scaled up or down as needed by adjusting the dryer dimensions. The dryer itself is an indirect solar dryer, developed and field-tested together with farmers in Bhutan and Nepal over multiple development cycles. <br/><br/>While this manual describes the construction process when using wood as the main body material, the same design can be used for steel-based solar dryers as well. Builders are encouraged to apply their own judgement, and explore different ways of adapting or improving the design as needed to suit local conditions and material availability.<br/><br/>Please note that this manual is provided as-is for informational purposes. SolarFood is not liable for any injury, damage or loss resulting from construction, transportation or use of dryers built using this manual. Dryer performance will also vary depending on factors such as materials used, workmanship, climate conditions and drying load.<br/><br/>This manual is distributed under a CC-BY license. Anyone is free to distribute, remix, adapt, and build upon this manual, as long as attribution is given to SolarFood.<br/><br/><br/>Background<br/><br/>The SolarFood project is an international developmental research collaboration led by Lund University and Ruralis. The aim of the project is to reduce post-harvest losses in Bhutan and Nepal through the development of efficient, affordable and locally adapted solar dryers. The project has been running since 2021, funded by the Swedish Research Council (VR-2020-04071) during 2021-2025, and the Research Council of Norway (project number 352437) during 2026-2028.<br/><br/>As mentioned, the solar dryer design described in this manual is the result of multiple iterative development cycles carried out in close collaboration with local farmers, carpenters and research partners, including Kathmandu University (KU) in Nepal and Jigme Namgyel Engineering College (JNEC) in Bhutan. Both steel and wooden versions exist. The wooden version is cheaper and easier to construct, and is suitable in non-rainy weather, while the steel version is more suitable for wet climates.<br/><br/>Unlike many other dryers on the market, the indirect solar dryers developed within SolarFood utilise a cheap heat exchanger to recycle heat from the hot, moist air before it leaves the dryer. This significantly increases efficiency of the dryers with only a minor cost increase. The fans are the only components requiring external power, and they draw only a few W in total, which keeps the running costs low.<br/> <br/><br/>In case of questions, suggestions for improvement or other input, we would be happy to hear from you. Please contact Professor Martin Andersson at martin.andersson@energy.lth.se.}},
author = {{Andreasson, Noah}},
institution = {{Lund University}},
language = {{eng}},
title = {{Construction manual and 3D-model : SolarFood Indirect solar dryer, generation 2}},
url = {{http://dx.doi.org/10.5281/zenodo.20401617}},
doi = {{10.5281/zenodo.20401617}},
year = {{2026}},
}