A review of nocturnal cooling systems for space cooling is presented. The cooling systems are grouped into two broad categories, namely, the air cooling system and the water cooling system. Their performance, uses and applications, and the factors considered for their selection are reported. Also, studies aimed at determining the quantities of net night sky radiation in different locations are reviewed. Generally, most locations can provide net night sky radiation above 40 W/m², while the nocturnal coolers have the potential for reducing space temperatures by between 2 and 4°C and can yield 14−48% savings in the energy demand of a building. Actual field testing experience, together with the prospects and problems that affect popularization of the systems, are also presented. Possible solutions are suggested.

A work on the analysis of five kinetic models for predicting methane yield is presented. The selected five common models for predicting methane yield include Gompertz, logistic, first-order, Richards and transfert models. Anaerobic digestion of orange and banana peels was simulated using the selected models. A comparative analysis of the models was carried out to determine the best-fit model. When predicting the methane yield of banana peels, all models reached a maximum of 99.23% and the model which was most accurate was the Gompertz model with 76% cumulative deviation and the least accurate model was the transfert model with 274.7% cumulative deviation. The prediction of methane yield on orange peels was 99.49% accurate for all models having the most accurate model being the Gompertz and first-order kinetic model with a cumulative deviation of 20.67% and the least accurate model being the transfert model with a cumulative deviation of 112%. This work presents the simulation considerations and application for each model.

Preservation of banana through drying is a recommended method for improving the shelf life. In this study, an experimental and theoretical evaluation of a developed forced-convection indirect solar drying system with a double-pass solar collector (DPSC) was undertaken. Experimentation using banana slices of 4 mm thickness was carried out. The DPSC achieved an optimal peak outlet temperature of 72°C with a maximum operational efficiency of 72.5%. A computational fluid dynamic (CFD) model was developed for prediction of the dryer temperature and 3D airflow distribution within the dryer unit using ANSYS 18.2. The CFD model was validated using experimental data and good agreement was achieved. The developed dryer demonstrated improved efficiency over similar dryers, and this is attributable to the unique arrangement of component parts. Dried banana chips were evaluated for quality through taste, color and shape and the results indicated good quality products. This was attributed to the pretreatment of banana chips with lemon juice prior to drying.