To overcome the challenges of crop spoilage and high operating costs, solar cold storage are the most effective solution today.
Crop spoilage in farms is a major obstacle that India faces. Erratic supply of electricity causes electricity-powered cold storages to remain inactive and storage conditions inside to not remain in the optimal range. On the other hand, diesel generator-driven storage units come with challenges of their own. To overcome these odds and prevent losses, solar-powered cold storages are the most effective solution today.
Challenges that solar storage addresses
Annually, 30 per cent crops, on an average, perish in India due to lack of proper cold storage facilities. Ram Bheke, business development manager, Promethean Power Systems, an India-based cold storage solution provider, says, “Traditional cold storages are associated with high operating costs. For instance, running a complete storage system on diesel has huge expenses associated with it, in the form of price of fuel, maintenance and other associated costs. Moreover, such systems are harmful for the environment.”
Reports suggest that these traditional setups increase the total running expenses by 28 per cent in addition to high instances of crop spoilage. Altogether, the producers face major financial losses.
Solar power comes to the aid here. Emeka Ekeocha, officer at Nigeria-based ColdHubs Ltd, says, “Solar-driven cold rooms in farm clusters and markets help store the crops for much longer. These do not rely on the availability of electricity or exhaust diesel to run. This reduces the running costs of the systems and gives farmers a substantial increase in income.”
Benefits of solar cold storage
The biggest benefit of a solar cold storage unit is reduced dependency on grid supply or diesel. India’s abundant solar energy ensures that sufficient power can be saved in the battery or storage units associated with the setup, which can be used in low-light days without hiccups (like monsoons). Alternatively, it cuts down on the various costs associated with diesel generators. As a result, producers using traditional systems can reduce their operational costs by at least 20 per cent.
Post-harvest food spoilage rate is reduced by 80 per cent. Bheke says, “Among the different varieties of produce, leafy vegetables and fruits must be stored carefully. Such items with high water content can get easily spoiled otherwise. With consistent power, solar cold storages can increase the crop shelf-life by up to 10 days. Farmers can store their vegetables for longer until they get the right price.” This gives crop producers an increased income of about 25 per cent.
Alongside these, major collateral benefits for the environment—like massive reduction of carbon footprint and reduction of non-renewable resource depletion—are also achieved.
Bheke adds, “Farm owners can find alternate source of incomes as well. We know quite a few who have invested in large-capacity cold storages and rented out portions to other farmers from the area. This acts as an additional income while farm owners can get a payback on their investment quicker. Income through net metering is another option.”
The setup starts with a walk-in storage room, sized according to requirement, with various temperature- and relative humidity-regulatory devices (such as compressors and thermostats) in place. Desired temperature range for a cold storage is 5°C to 25°C. Relative humidity should be between 65 and 95 per cent. The room itself must be made of various insulating materials like polycarbonates for enhanced thermal regulation.
Solar panels collect solar energy and power the compressors and other appliances of the storage room. Compressors can be adjusted as per cooling requirements—shelf-wise or at room-level. The system can be made grid-connected or completely off-grid, as suitable. Excess energy can be stored either in batteries or thermal storage units.
High investment remains a major obstacle for such solutions to find large-scale acceptance. Bheke gives an idea, “A storage room setup of about three- to four-tonne capacity, including electric appliances and thermal storage units, costs about ₹ 400,000 to ₹ 500,000, while solar panels draw a separate cost. Tentative cost for the panels is ₹ 100,000 per kW capacity. The final price is calculated as per the panels and storage capacities required.” The overall cost is 30 to 50 per cent higher as compared to traditional cold storages. Lack of domestic production of solar hardware units is the major reason for this high cost.
The best way to invest is in groups. Bheke continues, “It may be difficult for an individual mid-scale farmer to invest in a store room. It is easier for a farmer union or a group to gather funds and invest in a store room for their common use.”
If batteries are used, these need to be changed every four to five years, which further adds to the operational cost. Altogether, the investment needs to be worked out.