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Analysis of wind speed data and annual wind energy potential at three selected sites in Iraq has been investigated in this study. The wind speed data was collected from the Weather Underground Organization (WUO) at stations elevation. Extrapolation of stations elevations used to estimate the wind velocities at 60 m, 90 m, and 120 m via wind shear law. The objectives were to analysis of wind speed data and to assess the wind energy potential for the selected sites. Computer code for MATLAB software has been developed and written to solve mathematical model. Results in the form of the measured and Weibull estimated of monthly and annual average of wind velocities ( , wind shear, wind velocity carrying maximum energy ( , most probable wind velocity ( , probability density function (PDF), cumulative distribution function (CDF), monthly and annual wind power density (WPD) and wind energy density (WED) were presents. At stations elevation, the (WED) was the best for Basrah, Amarah, and Nasiriyah respectively and the selected sites are suitable for off grid applications. While at selected heights it was best for Basrah, Nasiriyah, and Amarah respectively. Basrah at (60, 90, 120 m) and Nasiriyah at (120) are acceptable for connecting to power grid. KeywordsWeibull distribution, assessment of wind resource, Wind energy potential, Analysis of wind speed data.

The performance of double-pass counter flow (model A) and double-parallel flow (model B) solar air heater with V-grooved absorber plate are numerically investigated. The mathematical models are written based on energy balance equations for each element of both models. The matrix inversion method is used to numerically solve the mathematical models for solar intensity (I = 350 − 950 (W/m2)), ambient temperature (Ta = 20 (°C)), mass air flow rate range of (ṁ = 0.02–0.09 (kg/s)), and opening angle of V-grooved absorber plate of (Ø = 60°). The results are presented in terms of: Air temperature rise, useful heat gain, thermal efficiency, and thermo hydraulic efficiency. Obviously when air mass flow rate increases, model (A) produces the highest air temperature rise, useful heat gain, and thermal efficiency. As air mass flow rate increases, the thermo-hydraulic of model (B) also increases while thermo-hydraulic efficiency of model (A) decreases from air mass flow rate (ṁ = 0.05, 0.06 and 0.07 (kg/s)) for solar intensities (350, 650, and 950 (W/m2)) respectively. In terms of thermal efficiency, the model (A) is more efficient than of model (B) by (26.8470 %, 27.8890 %, and 28.2496 %) for solar intensities (350, 650, and 950 (W/m2)) respectively. In terms of thermo-hydraulic efficiency, model (A) is more efficient than that of model (B) by (12.1046 %, 20.6830 %, and 25.1215 %) for solar intensities (350, 650, and 950 (W/m2)) respectively.

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