International Journal of Renewable Energy Technology (4 papers in press)
Short term solar energy forecasting using GNN integrated Wavelet based approach
by Priyanka Chaudhary, Mohammad Rizwan
Abstract: The power generation from solar energy is gaining more attention because of advancement in the solar photovoltaic technology including enhanced efficiency of solar cells by incorporating the good materials. In the present scenario the bidding of power is done on 15 minutes basis by many distribution companies. Keeping in mind aforesaid, 15 minutes ahead short term solar energy forecasting has been done and presented. As the power from solar energy is fluctuating and nonlinear in nature, the results obtained from mathematical models are not found satisfactory. Therefore, an intelligent approach based on wavelet transform and generalized neural network (GNN) is developed and applied for the short term solar energy forecasting problem. The results obtained from the proposed model are evaluated on the basis of statistical indicators like root mean square error (RMSE) and mean absolute error (MAE). It is concluded that the performance of the proposed model is found better as compared to GNN model.
Keywords: Generalized neural network; wavelet transform; grid integrated solar PV systems; solar energy forecasting.
Empirical model for prediction of density and water resistance of corn cob briquettes
by Simeon Jekayinfa, Ralf Pecenka, Ifeolu Orisaleye
Abstract: Biomass obtained from agricultural wastes have a high potential for energy generation, particularly in developing countries. The poor properties of the agricultural biomass cause handling problems and limit the suitability as fuel in conventional grates. Densification of biomass into briquettes enhances its fuel properties. In this study, effects of pressure (9, 15 MPa), temperature (90, 120
Keywords: Biomass briquette; densification variable; corn cob; empirical model; density; water resistance.
Special Issue on: ECRES2018 Advances in Renewable Energy
Investigation of the efficiency of a solar dryer with thermal storage by rock salt and by pebble bed
by HICHAM EL FEROUALI, AHMED ZOUKIT, ISSAM SALHI, SAID DOUBABI, NAJI ABDENOURI
Abstract: Storage materials by salt rocks and pebbles were introduced in an indirect solar dryer. Experiments were carried out by using rock salt and pebbles (0.076m3) as thermal storage materials. To overcome the thermal behaviour with storage materials, the solar dryer was modelled by SolidWorks flow simulation. Rock layers were arranged as superimposed sphere beds. The maximum reached temperature during the sunny period and the duration of the thermal discharge phase are strongly affected by the location of rocks in the drying chamber. These storage media maintained consistent the drying chamber temperature in the absence of the solar radiation by four more hours. Experimental tests were performed on lemon with and without the storage medium. Finally, the insertion of storage medium could increase the dryer efficiency by about 13.83%. Pebbles seem to be more suitable for thermal storage not for their thermal capacity but especially for their density.
Keywords: CFD modelling; thermal storage; pebble bed; rock salt; dryer efficiency.
Special Issue on: Sustainable Energy Technologies
STUDIES ON HYDROGEN FUELLED STATIONARY C. I. ENGINE OPERATED END-UTILITY SYSTEM
by Vinod Singh Yadav, Dilip Sharma, S.L. Soni
Abstract: The refineries turned in a better performance with their cumulative 181 million tones crude throughput, almost 7 per cent more than the previous fiscals achievement and a little over 2 percent of the planned target. The world is presently confronted with the twin crisis of fossil fuel depletion and environmental degradation. Combined residential and commercial energy demand is expected to increase in order to meet the expected increase in electricity demand as the worlds population shall grow and more people shall move to urban areas with access to electricity. The search for an alternative fuel, which promises a pleasant link with sustainable development, energy conservation, management, efficiency, and environmental safeguarding, has become highly noticeable in the present context. rnIn this investigation, fresh air with hydrogen enrichment was used as intake charge in a C. I. engine. Experiments were conducted on a 1-C, 4-S, air-cooled, stationary direct-injection diesel engine (Kirlosker TAF1) with maximum 1500 rpm and maximum 4.4 kW capacity coupled to an electrical generator. The injection timing (17
Keywords: Hydrogen-Enrichment; Injection timing; Flow rate of hydrogen; Performance.