Wireless transmission of metering data from a photovoltaic solar home system via global systems for mobile communication (GSM) short message service (SMS)

This paper focuses on the area of remote solar home system metering in an effort to bridge solar energy management in the industry with information technology (IT). A wireless platform was designed using ordinary mobile phone handsets to relay real time digital metering data from a remote PV solar home system via a GSM short message services to a central server (private computer). Here, we experimentally demonstrate the concept of a wireless data transmission of digital direct current (DC) metering data, based on simple and cost‐effective telecommunication technologies through programmed microcontroller circuits that connects to two mobile phones (client and server sets). A set of data was obtained through direct cable connection (meter‐adaptor‐PC) and also through wireless connection (meter‐GSM‐adaptor‐PC). The microcontroller at the server end extracted and decoded data from the received SMS (for wireless connection) and relayed the data to the data adaptor. The applications software in the PC downloaded the data from data adaptor and grouped it into clusters. Statistical graphs were plotted from the clustered data and real time virtual metering data was displayed at the PC. From the results, data received from the wireless transmission mode matched the real time data on the meter display but with short time lapses due to SMS delivery delays. The data from direct cable connection was highly reliable because data streamed live from the meter to the data adaptor. It was also observed that the GSM‐SMS was practical to the extent that programming errors were eliminated and the network is reliable enough to reduce data transmission inefficiencies. Further work on a dedicated, efficient, and an all‐in‐one meter with wireless transmission capabilities is required for wide scale adoption of the technology. This technology can find applications in off‐grid electrification where investors can sell power through aggregated solar home systems instead of establishing grid connected solar farms. Solar energy can also be quantified to qualify for clean development mechanisms so as to benefit from carbon finances.Key words: PV solar home system, DC power meter, GSM, data adaptor softwar

Characteristics of Different Systems for the Solar Drying of Crops

Solar dryers are used to enable the preservation of agricultural crops, food processing industries for dehydration of fruits and vegetables, fish and meat drying, dairy industries for production of milk powder, seasoning of wood and timber, textile industries for drying of textile materials. The fundamental concepts and contexts of their use to dry crops is discussed in the chapter. It is shown that solar drying is the outcome of complex interactions particular between the intensity and duration of solar energy, the prevailing ambient relative humidity and temperature, the characteristics of the particular crop and its pre-preparation and the design and operation of the solar dryer

Application of superabsorbent polymers (SAP) as desiccants to dry maize and reduce aflatoxin contamination

The ability of superabsorbent polymers (SAP) in drying maize and controlling aflatoxin contamination was studied under different temperatures, drying times and SAP-to-maize ratios. Temperature and drying time showed significant influence on the aflatoxin formation. SAP-to-maize ratios between 1:1 and 1:5 showed little or no aflatoxin contamination after drying to the optimal moisture content (MC) of 13 %, while for ratios 1:10 and 1:20, aflatoxin contamination was not well controlled due to the overall higher MC and drying time, which made these ratios unsuitable for the drying process. Results clearly show that temperature, frequency of SAP change, drying time and SAP-to-maize ratio influenced the drying rate and aflatoxin contamination. Furthermore, it was shown that SAP had good potential for grain drying and can be used iteratively, which can make this system an optimal solution to reduce aflatoxin contamination in maize, particular for developing countries and resource-lacking areas

GIS-NaP1 zeolite microspheres as potential water adsorption material: Influence of initial silica concentration on adsorptive and physical/topological properties

GIS-NaP1 zeolite samples were synthesized using seven different Si/Al ratios (5–11) of the hydrothermal reaction mixtures having chemical composition Al(2)O(3):xSiO(2):14Na(2)O:840H(2)O to study the impact of Si/Al molar ratio on the water vapour adsorption potential, phase purity, morphology and crystal size of as-synthesized GIS-NaP1 zeolite crystals. The X-ray diffraction (XRD) observations reveal that Si/Al ratio does not affect the phase purity of GIS-NaP1 zeolite samples as high purity GIS-NaP1 zeolite crystals were obtained from all Si/Al ratios. Contrary, Si/Al ratios have remarkable effect on the morphology, crystal size and porosity of GIS-NaP1 zeolite microspheres. Transmission electron microscopy (TEM) evaluations of individual GIS-NaP1 zeolite microsphere demonstrate the characteristic changes in the packaging/arrangement, shape and size of primary nano crystallites. Textural characterisation using water vapour adsorption/desorption, and nitrogen adsorption/desorption data of as-synthesized GIS-NaP1 zeolite predicts the existence of mix-pores i.e., microporous as well as mesoporous character. High water storage capacity 1727.5 cm(3) g(−1) (138.9 wt.%) has been found for as-synthesized GIS-NaP1 zeolite microsphere samples during water vapour adsorption studies. Further, the total water adsorption capacity values for P6 (1299.4 mg g(−1)) and P7 (1388.8 mg g(−1)) samples reveal that these two particular samples can absorb even more water than their own weights