Models for the Management and the Development of Hybrid Energy Systems: Case Study of Cameroon

My research begins with a literature review on past and ongoing research studies in the field of hybrid energy systems for remote areas with the objectives of (i) review the different schemes of hybrid energy system in islanding mode for remotes areas; (ii) focus on widely use optimization approaches for design and modeling of hybrid microgrids for electrification in remote areas; (iii) focus on photovoltaic, wind, fuel generator with/without storage; (iv) focus on four specific topologies of hybrid microgrids with or without storage system (PV; Wind; PV+Wind; PV+Wind+Diesel generator); (v) look for the advantages and the disadvantages of each topology of hybrid microgrid. The study reveals the diversify types of hybrid microgrids in the world depending on geographical locations, the variability definitions and applications of microgrids (from W to MW). The investigation result demonstrates the important role played by storage systems in electrification of remote areas. The second step was the acquisition data of solar irradiation and wind speed in all the ten regions of Cameroon. The objectives of this study was (i) have a reliable information about the irradiance and wind speed across the country; (ii) assess the potential of solar and wind energy; (iii) estimate of the hourly output power, the daily and yearly energy production of a PV panel and a wind generator; (iv) used solar and wind energy assessment to boost rural electrification in remote villages and contribute to energy supply; (v) use the solar and wind assessment to identify precisely the site for the future case study (Salak village). This study concludes that the Northern regions (Far North, North and Adamawa) have the highest wind Potential andmoving from the North to the South of the country, the average means wind speed decreases and the quite uniform distribution of solar radiation across the country when moving from North to South. This work finally confirmed that Cameroon has a good potential of solar and wind that can help to electrify remote villages across the country. The next step has been the assessment of hydro power plan potential. The objectives of this study was: (i) the identification of rivers that can be hugely exploited for hydroelectricity production; (ii) assess the potential of hydro power plants; (iii) use all the solar and wind potential for electrification and compensate the difference with hydro power plant. The result of this study shows that, according to the energy system distribution structure in Cameroon, the combination of different renewable energy sources with high fluctuations and hydropower can be reliable and cost effective solution for a growing energy demand. Finally the case study of the community of Salak in the Far North Cameroon which aims to propose an optimal design of hybrid energy eystems for rural electrification. The objective is (i) design and implement a model of hybrid energy system for rural electrification of the Salak village community; (ii) size and design a water production and distribution system; (iii) create an open source model simulator for optimal size and design of a hybrid energy system for rural electrification. The battery is modelled including its lifetime for economic evaluations using the rainflow counting method. The diesel generator must work inside its best efficient area of operation and a wide research has been done to retrieve such data for small size generators. An open source model has been built to help users in optimal size, design and management a hybrid energy system for rural electrification. This open source model demonstrates to be feasible for design, size and management of hybrid energy systems. This proposed hybrid energy system would not only resolved the electrification problem of the Salak rural area but could also preserved environment, help improving the quality of life by raising the level of the services

Hybrid energy systems for remote areas and the role of storage

This paper presents a review of different schemes of hybrid energy systems (HES) in islanding mode for remote areas with a focus on solutions for remote electrification which are basically composed by one or a mixed of different energy sources and storage systems. The paper analysis the widely used mathematical approaches for optimization, sizing and modeling of HES for isolated electrification areas including the role of storage system. This paper also analysis the advantages and disadvantages of different solutions proposed

Harmony Search Algorithm Based Management of Distributed Energy Resources and Storage Systems in Microgrids

Microgrids are composed of distributed energy resources (DERs), storage devices, electric vehicles, flexible loads and so on. They may either operate connected to the main electricity grid (on-grid operation) or separated from the grid (islanded operation). The outputs of the renewable energy sources may fluctuate and thus can cause deviations in the voltage magnitudes especially at islanded mode. This may affect the stability of the microgrids. This paper proposes an optimization model to efficiently manage controllable devices in microgrids aiming to minimize the voltage deviations both in on-grid and islanded operation modes. RSE Distributed Energy Resources Test Facility (DER-TF), which is a low voltage microgrid system in Italy, is used to verify the algorithm. The test system's data is taken through an online software system (REDIS) and a harmony search based optimization algorithm is applied to control the device parameters. The experimental results show that the harmony search based optimization approach successfully finds the control parameters, and can help the system to obtain a better voltage profile