American Journal of Energy Research

Extensive research has been conducted on centrifugal compressors to investigate the influence of diffuser features on the stage performance. However, there are several geometrical parameters affecting the diffuser performance and the unsteady interaction with the rotating impeller which makes the appropriate selection of the optimum features more complex. Furthermore, the trade-off between the efficiency improvement and operating range extension necessitates the need for an optimization tool to decide the typical diffuser configuration. Hence, this paper aims to introduce a multi-decision optimization approach to define the overall diffuser characteristics based on the specified duty requirements. This approach uses the most recent developed models in this field to evaluate the impact of different diffuser types on the overall stage performance technically and economically. From the performance prospective, the influences of diffuser geometry have been utilized to study the impact on stage efficiency and stable flow range. Furthermore, this has been also discussed economically as a function of the diffuser losses cost in order to make the typical decision.

American Journal of Energy Research. 2015, 3(2), 37-48. DOI: 10.12691/ajer-3-2-4
Pub. Date: January 16, 2016

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Experimental Characterization of Municipal Solid Waste for Energy Production in Niger Republic

by OUMAROU Mohammed Ben

Original Research

Solid waste management and energy generation have been of major concern in Niger Republic. Municipal solid waste samples were collected during the months of February, March and April and during the rainy season in August for three years in Diffa, Dosso, Maradi, Niamey and Zinder in Niger Republic. The refuse physical characteristics were then evaluated by sifting through the waste and separated into wood, grass, metal, plastic, paper and sand. The refuse samples were analyzed by proximate and ultimate analyses using ASTM standards. Proximate and ultimate analyses results of refuse in the area of study showed refuse characteristics as moisture: volatile matter: fixed carbon: ash content, as 19.693: 26.877: 19.310 and 34.120 for Niamey and 17.539: 25.950: 19.111: 37.40 for Zinder. The standard deviation and the mean deviation of the lower calorific value were found to be 7.35% and 1.60 % respectively for the five cities in the study area. The lower calorific values of the refuse were low and found to fall below the limit for the production of steam in electricity generation, therefore would not to be able to sustain an industrial incineration process. There is need to provide a supplementary fuel in the form of bagasse, any herbaceous biomass at up to 50% of the total fuel to be loaded in the incinerator. It was found that population density and geographical locations are not real determining factors as whether refuse quality may change or not but rather the life style of the population and its awareness towards waste management techniques like recycling, re-use and composting.

American Journal of Energy Research. 2015, 3(2), 32-36. DOI: 10.12691/ajer-3-2-3
Pub. Date: January 13, 2016

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Sonication Derived Powdered Mixtures of Ferrite and Ceramic Nanoparticles for H2 Generation

by Vinod S. Amar, Xavier M. Pasala, Jan A. Puszynski and Rajesh V. Shende

Original Research

This paper reports sonication derived powdered mixtures of NiFe2O4 and ceramic nanoparticles such as ZrO2/Y2O3/YSZ for H2 generation from thermochemical water-splitting process. To prepare powdered mixtures, NiFe2O4 (75 wt%) and ceramic nanoparticles (25 wt%) were placed in ethanol, sonicated for 120 min, and the slurry obtained was dried at 50°-100°C. Using these powdered mixtures, ten consecutive thermochemical cycles were performed at 900°-1100°C for H2 generation. Among different powdered mixtures, NiFe2O4/ZrO2 produced a maximum H2 of 30.6 mL/g/cycle at NTP conditions. Powdered mixtures prepared with different sonication times (30-120 min) and ZrO2 nanoparticles loadings (10-35 wt%) were also investigated for H2 generation via thermochemical water-splitting process. Sonication derived NiFe2O4/ZrO2 powdered mixture prepared at optimized conditions has produced average H2 volume of 38.8 mL/g/cycle during five consecutive thermochemical cycles, which was found to be higher than the H2 volume generated by NiFe2O4/Y2O3 and NiFe2O4/YSZ powdered mixtures. In addition, these powdered mixtures were characterized for powdered x-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) specific surface area, and scanning and transmission electron microscopy (SEM and TEM).

American Journal of Energy Research. 2015, 3(2), 25-31. DOI: 10.12691/ajer-3-2-2
Pub. Date: December 19, 2015

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Optical Analysis in CH₃NH₃PbI₃ and CH₃NH₃PbI₂Cl Based Thin-Film Perovskite Solar Cell

by Wayesh Qarony, Yesmin Ara Jui, Gloria Mithi Das, Tashfiq Mohsin, Mohammad Ismail Hossain and Syed Nurul Islam

Original Research

The optics of organic-inorganic halide perovskites materials in thin-film smooth surface p-i-n solar cell has been studied. The study was conducted for CH₃NH₃PbI₃ perovskite material, used as a photoactive layer and sandwiched between ultrathin electron transport layer of TiO₂and hole transport layer of P3HT. The investigation was carried out based on the optical wave propagation simulation results of quantum efficiency and short circuit current. A reference model of solar cell exhibits a maximum of 21.79 mA/cm² short circuit current as well as 76% of external quantum efficiency (EQE) for 620 nm to 700 nm of spectral range of wavelengths. Analyzing the influence of thickness for each layer on the short circuit current and the quantum efficiency the cell was optimized. Finally, a comparative analysis has also been done between CH₃NH₃PbI₃ and CH₃NH₃PbI₂Cl perovskite thin-film solar cell, where CH₃NH₃PbI₂Cl based solar cell gives 2.7% higher short circuit current and around 7.5% higher photon absorption, particularly in the near infrared red regions of spectrum (700 nm- 800 nm) and for the 360 nm of absorbing layer. Throughout the research, a Finite Difference Time Domain (FDTD) based Maxwell’s curl equations solver was used.

American Journal of Energy Research. 2015, 3(2), 19-24. DOI: 10.12691/ajer-3-2-1
Pub. Date: September 18, 2015

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19489 Views6927 Downloads26 Likes2 Citations