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Forced-Air Evaporative Cooling Chambers

Off-grid pre-cooling of fruits and vegetables

Forced-air evaporative cooling is well suited to provide rapid pre-cooling and improved storage of fruits and vegetables.

    

Chambers with this design typically cost less than half the cost of a refrigerated cold room.​

Features of a forced-air evaporative cooling chamber
  • Provides the greatest value in hot and dry climates

  • Ideal for fruits and vegetables that store well in high humidity environments

  • Forced airflow is ideal for rapid pre-cooling

  • Lower energy consumption and half the cost of refrigerated cold rooms

  • Can be powered by off-grid solar energy systems

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Extending vegetable shelf-life 

​The images to the left are from an experiment with a forced-air evaporative cooling chamber in Kibwezi, Kenya. 

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The shelf life of spinach is extended from 2 days to over 5 days when stored in the chamber, compared to storage in a basket placed in the shade outside of the chamber. â€‹

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The CoolVeg team has designed, tested, and deployed several types of forced-air evaporative cooling chambers

  • Shipping container based cooling chamber: 

​       Large storage capacity

  • Portable cooling chamber:

​       Least expensive and easiest to make. 

  • Mobile cooling chamber:

​       For use in transportation applications.​

Shipping container based forced-air evaporative cooling chamber

Storage capacity of 168 crates

Led by CoolVeg founder Eric Verploegen, a team at MIT designed a forced-air evaporative cooling chamber that can be built in a used shipping container. Detailed documentation of this open-source design can be found below.

Pilot chambers were built and tested in partnership with Hunnarshala Foundation in Bhuj, India and Solar Freeze in Kibwezi, Kenya.

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Portable forced-air evaporative cooling chamber

Storage capacity of 15 to 30 crates

CoolVeg developed the modular forced-air cooling chamber concept with support from Efficiency for Access' R&D Fund. This design is easy to construct, can be tailored to meet users' capacity requirements, and can be carried by 6 people or transported on a small truck. Testing of these chambers is underway in India and Nigeria.

Mobile forced-air evaporative cooling chamber

Storage capacity of 32 to 64 crates

CoolVeg developed the mobile forced-air cooling chamber in partnership with Cold Hubs in Kaduna, Nigeria, and support from Efficiency for Access' R&D Fund. This chamber is designed to allow fruits and vegetables to be picked up at farm gates and pre-cooled while in transit on rural roads to markets. 

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Video: Cooling Chamber in Kenya

Components of the Airflow System

The diagram below is a head-on cross-sectional schematic of a shipping container based forced-air evaporative cooling chamber. The key components of the chamber's airflow system are labeled.

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Work With Us

CoolVeg is available to partner with organizations interested in commercializing this technology, which is particularly well-suited for rapid pre-cooling when energy access is a constraint.

CoolVeg Foundation Inc. is a 501(c)(3) nonprofit organization. Tax ID # 93-4155665

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