الفهرس 
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Abstract
Rapid increase of world population and global energy consumption
represents a great scientific and technical challenge for power generation industry
to supply sustainable clean environment- friendly energy. However, it is a clear
fact now that fossil fuels are not capable of meeting future energy requirements
due to the harmful gas emissions. Furthermore, climate change due to carbon
emissions increased the necessity of renewable energy source (RES) deployment
that contributes to the ecological development. Thus, electrification using
efficient utilization of on-site energy resources has recorded significant progress.
RES such as wind, solar have been widely well-known as efficient ways to
overcome the consequences of depending on fossil fuels and facing the
significant increases in CO2 emissions.
Single RES systems face difficulty to maintain balance between the required
and generated energy because of its unpredictable nature due to weather changes.
Fortunately, the problems caused by variable nature of these resources can be
partially overcome by integrating different RESs to construct hybrid renewable
energy system (HRES). Hence, HRES is a flexible, reliable system that can be
adapted depending on the application site, demanded power, and any other
requirements.
The optimal hybridization of RESs is essential process for designing the
HRES to prevent shortage and utilize the excess energy. In this regard, design a
holistic energy management strategy for HRES is proposed in order to achieve
efficient use of the available RESs to cover a specific load from technical,
environmental, and economic points of view. This strategy can ensure the
robustness of the HRES to avoid system blackouts when the generated energy
from RESs is insufficient to cover the required load. It can also minimize the
dependability on the backup diesel generator (DG) in order to save energy costs
and decrease the harmful environmental emissions.
Hence, the main objective of this study is designing a detailed framework of
a holistic energy management strategy for HRES which includes techno-enviroeconomic parameters considering demand side management (DSM). Therefore,
different approaches had been proposed for application as follows: standalone
HRES which comprises of PV, WT, batteries and diesel generator had been evaluated using HOMER then multi-criteria decision-making (MCDM) approach
is used to rank the optimal HRES alternatives based on the scheme rank.
Furthermore, the hybridization between the RESs and the main utility grid has
been evaluated considering DSM using Genetic algorithm which is proposed to
determine the optimal operating hours for the shiftable profile load and the
shiftable volume load.
All the parameters such as NPC, Cost of Energy (COE), CO2 emissions and
Renewable Fraction (RF) are considered through proposing the suitable dispatch
strategy of HRES; cycle charging and load following. Then the demand side
management (DSM) is implemented. The applied DSM includes demand priority
categorization, peak-shaving and load shifting for moving loads from high-peak
toward off-peak periods to achieve a smoother utility demand profile. It can
increase the utilization of the RES generated energy, minimize COE, as well as
increase the RF and decrease the realistic environmental impacts. Additionally,
it can avoid the grid blackouts and increase the HRES reliability. Finally, a
sensitivity analysis is performed for the fluctuation of energy demand, fuel price
and RES to define the benefits of DSM.
The results showed that the case considering DSM strategy for standalone
HRES gave better outcome than the base case. Significant reduction in NPC,
capital cost, BBS cost and fuel cost and COE is obtained. The percentage
reduction for the previous factors are; 14.84 %, 14.93 %, 55.9%, 25.6% and 14%
respectively. Also, it was observed that the battery bank sizing and DG fuel
consumption decreased by 57% and 25.6% respectively.
The results also showed that the grid connected HRES; considering DSM,
produces energy at very low cost compared to the utility tariff, (about 59% of the
tariff) and without any increase in the expenses of DG’ fuel costs. The resulting
RF was around 95%, which means that only 5% of the required energy is covered
from the main grid. Additionally, the annual CO2 emissions had been decrease
by 93.5% comparing to full reliance on utility grid.Keywords: - Hybrid energy system; Energy management; Renewable energy; Demand side
management; Solar energy; Wind energy.