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This work explores the effect of latent heat storage on the performance of a passive‐type mixed‐mode greenhouse dryer for groundnuts drying. Experiments were conducted for mixed‐mode greenhouse groundnuts drying (MMGGD), modified mixed‐mode greenhouse groundnuts drying (MMMGGD), and open sun groundnuts drying (OSGD) under the climate of Hisar (India). Average convective heat transfer coefficients for MMGGD, MMMGGD, and OSGD were 0.738, 0.607, and 0.555 W/m2 °C, respectively, and the respective average evaporative heat transfer coefficients were 113.304, 41.483, and 14.266 W/m2 °C. Energy and exergy efficiencies were found higher for MMMGGD, whereas the specific energy consumption was found lower as compared to MMGGD. Statistical analysis has shown the appropriateness of the page model for predicting the thin‐layer drying behavior of groundnuts for MMGGD, MMMGGD, and OSGD. The lower value of energy payback time (4.47 years) and the higher value of CO2 mitigation (953.299 tons) for MMMGGD show the environmental suitability as compared to MMGGD. Practical applications: The present study focuses on the development of drying systems to prevent post‐harvest losses in groundnuts due to moisture and uncontrolled weather conditions. The temperature range of the proposed modified mixed‐mode greenhouse dryer is suitable for drying for most of the agricultural commodities. This drying system can be used for a range of food crops in different small and medium industries. Due to electrical independence, the proposed system seems best suited for small farms and farmers in remote and rural areas. The modified mixed‐mode greenhouse may also be used as a field‐based storage house for grains and freshly harvested crops. [ABSTRACT FROM AUTHOR]

The groundnuts were dried inside an even span roof type free convection greenhouse dryer with a useful floor area of 1.2x0.8m² in the environmental conditions of Rohtak, India (28° 54'-N 76° 34'E). Wire mesh sieves of sizes 0.15x0.25 m², 0.25x0.4 m², and 0.35x0.6 m² were used to accommodate thin layer samples of groundnuts. The groundnuts were dried till the optimum safe moisture storage level (8%-10%) was attained. Based on experimental (hourly) observations the values of constants (C and n) in the equation of Nusselt number were evaluated. The values of convective and evaporative heat transfer coefficients were calculated which were observed to decrease with the increase in the sieve size. The overall average greenhouse thermal, energy, and exergy efficiencies were evaluated as 8.83%, 22.67%, and 2.75% respectively. The overall average experimental error in terms of % uncertainty for groundnuts drying was evaluated as 37.94%. [ABSTRACT FROM AUTHOR]

Peanut or groundnut is one of the major oilseed crops in the world. It is rich in oil and proteins. Developing countries account for about 95% of the world peanut production. Asia alone accounts for 70% of this amount where the major producers India and China together represent over two-third of global output. Traditionally, groundnuts are dried in open sun to its safe moisture level for storage. Natural and artificial (hot air drying) drying methods of groundnuts are being used throughout the world. Artificial peanuts drying devices consume very large amount of energy. In this paper, present status of peanut and a comprehensive review of its drying methods are discussed. Recent developments in preservation and storage of groundnuts are also highlighted. [ABSTRACT FROM AUTHOR]