Our Research Mobile evaporative cooling rooms for vegetable preservation


Can we commercialize a cold storage chamber using evaporative cooling that is lower cost than the currently available technologies? Can we reduce post-harvest losses of fruits and vegetables for farmers in rural off-grid communities?

Research Strategy

  • Conduct prototype testing and computer modeling to continue to improve the forced-air evaporative cooling chamber performance and design
  • Collaborate with existing cold storage providers and NGOs to pilot the technology with smallholder farmers in India and Kenya, and gather data from these pilots
  • Identify key markets and approaches for scaling the commercialization of forced-air evaporative cooling chambers
  • Develop and publish publicly available open-source designs of the technology and engage and support early adopters and promoters of the technology

Project description

J-WAFS Solutions Program

In many countries across the world, a significant portion of the food produced (30-50%) is lost before it reaches the table primarily due to high-temperature conditions. Forced-air evaporative cooling chambers have the potential to provide an effective, low-cost solution for postharvest fruit and vegetable storage in low-income regions with hot and dry climates. This innovative design, based on retrofitting shipping containers, will provide a lower-cost alternative to refrigerated cold rooms and a better-performing alternative to charcoal evaporative cooling chambers and non-climate-controlled environments. The water required to operate the chamber is only a small fraction of the water consumed in growing the food. Access to improved fruit and vegetable storage will reduce food loss, enable farmers to sell their produce at a higher price at different times of day, and improve access to nutritious food in the community. This Solutions grant will support the development, publishing, and promotion of publicly available open-source designs of the technology, along with continued testing of pilot chambers operating in Kenya and India, and engagement with early adopters of the technology.


  • Evaluated performance of forced-air evaporative cooling chamber at MIT, India and Kenya
  • Conducted market research and customer discovery interviews with nine cold storage providers in Africa and India and learned that forced-air evaporative cooling chambers are well suited to address the pre-cooling sector of the horticulture market
  • Constructed and deployed the first two full-sized pilot chambers with a Kenyan social enterprise called Solar Freeze, and an NGO in Gujarat, India called Hunnarshala Foundation 
  • Produced detailed documentation of the chamber design that is publicly available through a dedicated website with overview videos targeted at early adopters and promoters of the technology
  • Held online information sessions and workshops promoting the technology and the open-source documentation that were attended by 50 participants from over 10 countries
  • Established a consulting company, CoolVeg, that is focused on providing technical support to companies and other organizations looking to commercialize evaporative cooling technologies for post-harvest storage of fruits and vegetables

Additional Details

Impact Areas

  • Food

Research Themes

  • Technology & Commercialization
  • Sustainability & Adaptation
  • Transforming Food Systems
  • Equity & Access

Year Funded

  • 2021

Grant Type

  • Solutions Grant


  • Completed