Portable Forced-Air Evaporative
Cooling Chambers

Off-grid pre-cooling of fruits and vegetables

These portable chambers provide rapid pre-cooling and medium-term storage of fruits and vegetables for farmers, retailers, aggregation centers, and other users in hot, dry climates.

Portable cooling chambers are currently available for purchase in Kenya and Nigeria. Open-source designs, performance results, and research from the development and testing of the chambers are available below.

Interested in purchasing a chamber?

Kenya: Benson Maina — benson@coolveg.org
Nigeria: Nnaemeka Ikegwuonu — info@coldhubs.com

Commercialization in other countries: Eric Verploegen — eric@coolveg.org

Key Features

Provides the most value in hot and dry climates
Ideal for fruits and vegetables that store well in high-humidity environments
Storage capacity of approximately 15–30 standard produce crates
Can cool 500 kg of produce by 10°C in 6 hours using only 200 W
~2.4× more energy-efficient while operating than a comparable refrigerated cold room
Less than half the cost of a comparable refrigerated cold room
Can be powered by off-grid solar energy systems
Can be carried by approximately six people or transported on a small truck

Developed and tested with support from

Portable forced-air evaporative cooling chamber designs

CoolVeg's portable cooling chamber designs are open source and adaptable for local construction and different storage capacities.

Design documentation includes:

Materials and components for construction
Engineering and dimensional drawings
3D CAD renderings
Designs for multiple chamber sizes

Download portable chamber designs

Extending Vegetable Shelf-Life

In testing in Zaria, Kaduna, Nigeria, the shelf life of most vegetables was extended by 4 or more days, with produce lasting up to three times longer in the portable cooling chamber than when stored outside the chamber in the shade.

Red onions performed exceptionally well, with the shelf-life increasing from 14 days outside the chamber to more than 100 days in the chamber.

Research report

CoolVeg developed and tested the portable and mobile forced-air evaporative cooling chambers in collaboration with ColdHubs in Nigeria and Artisana in India, with support from the Efficiency for Access Research and Development Fund.

The project research report covers:

Chamber design
Thermal and shelf-life performance testing
User research
Economic analysis
Potential for commercial deployment

Download the summary report (3 pages)

Download the full report (96 pages)

Components of the Airflow System

Forced airflow draws cooled, humidified air through the produce crates to rapidly remove field heat. The cut-away diagram below shows the major components of the airflow pathway in a portable cooling chamber.

Work With Us

Portable cooling chambers are currently available for purchase in Kenya and Nigeria. CoolVeg is also interested in working with organizations that want to manufacture, commercialize, or deploy the technology in other countries.