Background:
Smallholder farmers in developing countries do not have easy access to cold storage with good control of temperature and humidity as they are energy intensive and expensive, involve a large initial capital investment, and require an uninterrupted electrical grid supply, which is not readily available in many farm communities. It is reported that postharvest losses in India is 25% to 30% due to lack of cold storage facilities and cold supply chain, and that these losses have lowered the per capita availability of fruits and vegetables and only 10% to 11% of the perishables are provided cold storage and that capacity needs to be increased by 40%. In India, there are 136.8 million small and family operated farms that have the potential to benefit from on farm or community coolers. :
Technology Details:
The solar refrigerated evaporatively cooled structure does not require grid (uninterrupted power supply) or batteries for its operation and maintains low temperatures by solar energy. This technology uses a combination of solar refrigeration and evaporatively cooled system and can achieve daytime temperatures as low as ~5-10 °C and nighttime temperatures below 14 °C, when the daily ambient maximum temperature reaches approximately 45 °C. The major innovations in this technology are mesh fabric structure, “wetted” fabric for evaporative cooling, split refrigeration evaporator coil for cooling water and air, a “water battery” for nighttime cooling, a sunlight sensing and remote control (using IoT) system for intelligent control of refrigeration system demand based on amount of sunlight present, a secure power supply inverter and a robust refrigeration system.