In this paper estimation of PFC (Primary frequency control) reserves and their adequacy has been investigated. Since Pakistan is aiming to add more renewable generation to its power system to reduce their dependency on fossil fuels and because of their concern about the environmental polution. And this renewable penetration adds variability and complexity to the power grid and doesn't add inertia to the system. So therefore overall inertia of the system decreases in result of addition of renewables. When the inertia of the system decreases, frequency deviations increases because of the renewable forecast error and other contingencies in the grid. To study thiese frequency deviations expected scenario for Pakistan power system are created for current and future Pakistan power system. From these studies, estimation of PFC reserves are made in this paper for future Pakistan power system. This paper also explain the frequency instability arises due to high renewable integration in power system and their feasible solutions for future Pakistan power system.

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Integration of renewable energy sources in power system has increased rapidly in recent years due to environmental effects such as climate change and global warming. Renewable sources provide clean and sustainable energy but it has some negative effects on power system. Renewable sources are mostly inertia-less sources and they increase instability in system. Frequency deviations are main indicator of their fluctuation because of their variable energy nature. To stabilize frequency, spinning reserves are there. Most of generators providing spinning reserves are fossil fuel generators, their operation is costly and not environment friendly. To minimize dependence on spinning reserves, demand side response is a method, which can provide frequency reserves cheaply and have a fast response. Demand side response is to shift loads of end users from peak hours to off-peak hours in response to frequency deviations or any contingency in power system with agreement with end users. This paper proposes the use of demand response through load management. Direct control method is used to control loads of end users. In response to frequency deviations, loads are ON/OFF to stabilize the frequency. For that purpose, a simple microgrid is designed in MATLAB/SIMULINK comprises of Solar PV and diesel generation sources. Loads are controlled through simple controller, which monitor frequency and act accordingly. Different scenarios are simulated, with demand side response and without demand side response. The results showed that with demand side response, frequency can be stabilizing quickly and system can be prevented from instability.