JournalTOCs

Journal of Renewable Energy
Number of Followers: 11

This is an Open Access Journal

Open Access journal
ISSN (Online) 2314-4386
Published by Hindawi

[339 journals]

Modeling of an Electrical Energy Switching System in Multisource Power
Plants: The Case of Grid Connected Photovoltaic and Wind Power Systems
- Abstract: This paper proposes a multisource power plant management strategy for the proposed structure. This power plant consists of photovoltaic, wind, and grid. The principle of this management strategy is based on the reference currents and defines two components of the current namely a harmonic component related to the harmonics contained in the load current and current called fundamental related to the fundamental of the load current. This proposed strategy allows the different renewable sources to supply the load partially or totally. The harmonic component performs the power quality function while the fundamental component feeds the load and injects the surplus production into the grid. The power management is done according to the established scenarios and responds to the demand of the load. The simulations were carried out with Matlab software, and these results show the performance of this strategy for this structure studied to fulfill the following functions: power supply to the load, power factor (PF) correction, harmonic elimination, reactive energy compensation, and injection in the network of a current with a low rate of harmonic distortion lower than 1% in accordance with the IEEE Std 519-2014 standard.
  PubDate: Mon, 28 Nov 2022 08:50:00 +000
DFT Studies of p-N,N-(Dimethylamino) Benzoic Acid with Para or
Meta–Electron Withdrawing or Donating Moieties for Dye-Sensitized Solar
Cells (DSSCs)
- Abstract: Solar energy is receiving considerable attention worldwide. Our contribution here focuses on fabricating p-N,N-(dimethylamino) benzoic acid (4-DMABA) donor-π-acceptor derivatives for use in dye-sensitized solar cells (DSSCs). The gas-phase and solvated 4-DMABA and some of its electron donating or withdrawing ortho or meta derivatives were studied theoretically. Density functional theory (DFT) and time-dependent DFT (TD-DFT) were applied to visualize their structural, molecular, photoelectrical, electronic, and photophysical parameters. The parameters for monitoring DSSC efficacies include HOMOs, LUMOs, energy gaps, wavelengths, oscillator strengths, light harvesting efficiencies (LHE), electron injection driving forces (ΔGinject), regeneration driving forces (ΔGregen), open circuit voltages (VOC), and short-circuit current densities (Jsc).
  PubDate: Sat, 22 Oct 2022 07:20:02 +000
Design and Optimization of a Wind Turbine for Rural Household
Electrification in Machakos, Kenya
- Abstract: Machakos is an area characterized by low wind speeds in the range of 0.5 m/s to 5 m/s with an annual average wind speed of 3.5 m/s. Maximum power generation from wind requires the appropriate design of the conversion system. In this study, two HAWT rotor blades were fabricated using Styrofoam and aluminium with a pitching mechanism to maximize power. The system was tested in a wind tunnel environment at a wind speed range of 0 m/s−20 m/s. RPMs and torque were measured and then used to calculate the TSR and power coefficients at different pitching angles. Energy optimization was performed by varying the pitch angles from 0 to 40 degree and rotational speeds, blade shape, and also a variation of blade materials. The analysis of tip speed ratios showed positive skewness implying high potential for significant energy generation at low wind speeds. At the rated wind speed of 5 m/s, Styrofoam blades performed optimally at a pitch angle of 20 degree with a tip speed ratio (TSR) of 2.1 corresponding to a Cp of 0.465. This translates to 238 W of power. Aluminium type performed optimally at a pitch angle of 15 degree with a TSR of 1.9 corresponding to a CP of 0.431, a power estimate of 220 W. These findings showed that Styrofoam blades were more effective and thus suitable for application in wind systems. The understanding gained from this study could be useful to the HAWT research community and can be extended to the turbine designs for small-scale microgrids and utility applications.
  PubDate: Thu, 15 Sep 2022 11:20:01 +000
Feasibility Study of a Hybrid PV/Hydro System for Remote Area
Electrification in Rwanda
- Abstract: Rwanda is among the least developed countries on the globe with total access to electricity not exceeding 63%, where the rest of the population lives in areas with no access to electricity. One such a place, which is the focus of this research, is Musanze district (1.4919 S, 29.5572 E), where 60% of the population in this area are located in remote areas, which makes the task of their electrification via grid system very difficult. Micro hydropower has been developed so far to reduce the deficit of energy access in this area. However, the power generated is not enough to cover the area, and the major problem is the decrease in river water level in the dry season, which affects the power generation. In this work, the feasibility of a hybrid PV/hydroelectric supply system is studied and optimized to increase the number of homes accessing electricity in this area. A 200 kW Mutobo micro hydro system in Musanze district under operation is considered a case study where a 100 kW PV array tied to the micro hydropower system is designed. The optimized PV-hydro hybrid system was proposed using a modified and O MPPT algorithm to enhance the PV-generated power. The model was designed and simulated using MATLAB/Simulink, and data recorded from Mutobo micro hydropower station, Rwanda Energy Group, and National Meteorological Agency were used to estimate solar energy potentials. The results showed that the hybrid PV/hydro system is feasible and effectively contributes to the power shortage mitigation in remote areas during the dry season.
  PubDate: Fri, 24 Jun 2022 08:05:03 +000
Renewable Energies in Ghana in Relation to Market Condition, the
Environment, and Food Security
- Abstract: Energy is essential to the development of a country, and several studies have been carried out on the production and use of energy by industrialised countries. However, little research and development has been carried out in developing countries on renewable energy. Also, the importance of traditional fuels such as biomass has not been emphasised in developing countries like Ghana, which rely on fossil fuels. Ghana relies heavily on imported petroleum fuel obtained from fossil fuels. However, fossil fuels are faced with many limitations including environmental pollution and an escalating price. Hydropower, biomass, biofuel, wind, and solar energy are the major renewable energy resources expected to be fully exploited in the future. This study, therefore, assesses the sources of the main renewable energy in relation to policy, the conditions of the market and food security. The government of Ghana has put in place a favourable business environment for the renewable energy sector by setting explicit feed-in tariffs (FITs). In addition, various acts and legislation have been passed and formulated by the relevant institutions (Renewable Energy Act (832) of 2011). The study revealed that there is an increase in the exploitation and use of energy from renewable resources when compared with the past decades. However, this exploitation is still limited due to barriers such as the cost of technologies, financing issues, and scientific and technical barriers.
  PubDate: Tue, 29 Mar 2022 22:20:00 +000