Impact of replacing thermal power plants by renewable energy on the power system

The Egyptian Electricity Holding Company (EEHC) has paid great attention to renewable energy sources; wind power (WP) and photovoltaic (PV). The EEHC Strategy aims at increasing the proportion of power totally generated from renewable energy sources (RES) to 20% by 2022. With increasing such amount of RES in the Egyptian electricity system, some of the on-line thermal power plants will be shut down and replaced by WP and PV. Thus the thermal reserve will be reduced making the available online thermal power plants fewer to share the regulation burden. The power system inertia will be reduced, the frequency deviation will be greater after system disturbance and more oscillation will occur. Therefore, this paper studies the impacts of increasing the renewable energy sources on the frequency control of the Egyptian power system by investigating different scenarios of increasing the RES to 20% after occurring sudden variations in generation. Also the impact of RES on environmental improvement is presented by calculating the expected annual CO2 emission reductions (ER), certified emission reduction (CER) and the amount of fuel saving. The model was created by using DIgSILENT power factory software.