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Aims: To estimate the optimum tilt angle and maximum solar power for different geoclimatic zones in Nigeria. Methodology: In this study, the surface data of direct and diffuse solar radiations spanning 2013 to 2017 were obtained from the archives of the Modern-Era Retrospective Analysis for Research and Application for 20 stations spread across Nigeria. To study the direct relationship between the solar power on a photovoltaic panel and the solar radiation, the values of the direct, diffuse, and ground-reflected components of solar radiation were calculated for six tilt angles ranging from 15° to 90° using anisotropic models. Afterwards, the maximum values of the solar power and the corresponding tilt angles, as well as the average number of solar panels that can be used to cater for the electricity needs of households in all the geoclimatic zones, were estimated. Results: Analyses showed that the maximum solar power was received at tilt angles of 30° and 45° from October till February, and tilt angles of 15° and 30° from March till September in all the study locations. For instance, the Sahel and Guinea Savanna zones had the highest solar power, whereas Derived Savanna and Coastal zones had relatively low power. Based on the results, it was determined that the number of solar panels required in the sahel zone would be lower than those of the other zones. Conclusion: It can be inferred from the results that the reception of maximum solar power is at the tilt angle of 45o in Sahel, Guinea, and Derived Savanah regions, and at 30o in the Coastal region. The results of this research will provide solar engineers with accurate information on the orientation and tilt of PV modules for efficient power generation.

Global spatial and annual distribution of surface water vapour density were estimated using 2005 -2016 monthly air temperature and relative humidity at 1° ×1° resolution obtained from Era interim and NCEP/NCAR database products. Obtained results from reanalysis were statistically tested using in situ data from Tropospheric Data Acquisition Network (TRODAN) of The Center for Atmospheric Research (CAR). Four seasonal variations of surface water vapour density (winter (DJF), spring (MAM), summer (JJA) and autumn (SON)) was examined. Observed result from the two reanalysis follow similar trends with value from Era interim leading. High values ranges between 50 g/m2 and 68 g/m2 were observed in tropical regions and humid sub-tropical regions. Low values ranges between 8 g/m2 and 38 g/m2 were observed in Ice cap, Tundra and arid regions. High warming may be experienced in tropical and sub-tropical regions, similarly, climate change with alarming rate may be experienced in locations with low values. The annual cycle of surface water vapor density is clearly established from two reanalysis across world classified into twelve regions. The statistical test for the reanalysis present good result with a mean bias error, MBE, root mean square error, RMSE and R square of 20.56, 18.29, 0.87 and 5.87, 0.98, 0.93 for Era interim and NCEP/NCAR respectively.

This study examines the wind power potential for different pressure heights in some Coastal and Sahel savannah stations in Nigeria. A 5-year hourly mean wind speed data at different heights and also at the hour of 00:00 and 12:00 were obtained from ERA Interim reanalysed data set. The data were statistically analyzed using Weibull distribution function. It was found out that Ikeja and Katsina stations have the maximum wind power density of 174.69 W/m2 and 196.88 W/m2 for both Coastal and Sahel savannah regions respectively at 100 m height and also at 12:00 hour of the day when there is occurrence of intensive wind speed as observed in the stations considered. Therefore, the analysis demonstrates the economic feasibility of using wind energy as a means of electricity supply at Ikeja in Coastal region and Katsina in Sahel savannah region of Nigeria. Thus, the wind power potential in these areas should be adequately harnessed which could be used to compliment the present power supply and reduce carbon dioxide emissions which contribute to global warming and lower long-term overdependence on fossil fuels in those areas and in Nigeria at large.

The Campanian Bida Formation is the oldest stratigraphic unit in the northern Bida Basin, central Nigeria. Facies analysis of the investigated sections indicates three main facies which include conglomerate, sandstone and claystone. The poorly sorted, matrix and grain supported conglomeratic facies which overly unconformably the weathered schists and granites is interpreted as gravity induced debris flow deposit. The massive to crossbedded sandstone facies with unidirectional paleo-flow dominantly to the NNE were deposited in braided fluvial channels. The sequence grades into claystone facies which probably was formed in localized non-marine floodplains. Results of grain size analysis; standard deviation and skewness which range from 0.65 to 1.69 and -0.02 to 0.96 (average values of 1.29 and 0.11f) respectively suggest that the sandstones are predominantly texturally immature and, thus, imply fluvial origin. Average mean sizes of 0.79f suggest predominance of coarse sands and this suggest that saltation is the most prevalent mode of transportation. Pebble morphology study also indicates mainly fluvial processes for the clasts from the conglomerates and conglomeratic sandstones. Few individual clasts with sphericity and Oblate – Prolate (OP) index values less than 0.66 and -1.5 respectively, however, provide evidence of recycling of some of the clasts from older sediments. Petrographic study reveals that quartz is the dominant framework grain ranging from 66.3 to 88.5%. Feldspar dominated by plagioclase type constitutes between 10 to 27.7%. The plotted QFR diagrams suggest subarkosic sandstones derived from rifted and uplifted continental basement rocks in a warm humid paleoclimatic setting.

The sedimentary facies of the Maastrichtian Enagi Formation exposed across the Agbona ridge at Share and Shonga areas was investigated for the first time to characterize their depositional facies and interpret the depositional environments. Well exposed vertical profiles of the sediments were studied along road cuts, erosional channels and cliff drops with special attention focused on their internal physical and biogenic attributes. The facies and facies associations in the lithostratigraphic units mapped include conglomerate, sandstone and claystone. The conglomerate facies is moderately sorted; grain supported and mature, showing evidence of reworking and recycling. Association of this facies with herringbone cross stratified sandstone beds probably indicates tidal channel lag origin. The sandstone facies are commonly compositionally mature, bioturbated and contain clasts of reworked clays and clay drapes and these suggest high energy tidal channels and shoreface. The associated unidirectional cross bedded sandstones subfacies and kaolinitic claystones are interpreted as braided fluvial channels and floodplain deposits. The gross sedimentation pattern and characteristics suggest predominance of trangressive shallow marine processes occasionally incised by fluvial channels. The clay deposit associated with the floodplains may offer economic resource potential in the area.

Coconut (Cocos nucifera) is one of the tropical nut fruits containing high percentage of dietary fibre among plant foods that are beneficial to human health. Rheological characteristics measurements for wheat cassava flour blends with the inclusion of coconut fibre were studied using the Mixolab, the standard “Chopin+”protocol. The flour blends were substituted with different levels of coconut fibre (0%, 5%, 10%, and 15%) and wheat-cassava flour blend was used as control. The effects of added coconut fibre on the rheological properties of composite dough of wheat and cassava (90:10 w/w) were evaluated. The maximum torque during mixing (C1), the protein weakening based on the mechanical work and temperature (C2), the starch gelatinization (C3), the stability of the starch gel formed (C4), the starch retrogradation during the cooling stage (C5) were determined. Results showed that the torque values in all the dough decreased with the inclusion of fibre except in CI and C2. The values of C1 and C2 (the dough development and the stability of proteins) increased with the increasing level of coconut fibre. Increasing level of fibre inclusion reduces the gelatinization of the cooked starch (C3), however 5% fibre dough (CNF) had the highest torque and the lowest torque was observed in 15% fibre dough (FPC), though the control sample (CTR) non fibre dough had the highest 2.15 Nm. Addition of fibre increased the dough stability from 6.60 to 8.58 minutes. It was observed that 15% fibre enriched (FPC) had the highest dough stability.