gas-fired , coal-fired and hydropower plants . Inertia determines how quickly the 50Hz AC system frequency will change when there is an imbalance between generation and demand . Inertia stabilises the frequency and reduces the RoCoF . The lower the level of Inertia on the system , the higher the RoCoF will be in the event of a sudden generation or demand loss .
As levels of solar photovoltaic / distributed renewable energy generation continue to increase in our future national energy generation mix portfolio , System Inertia is expected to decrease . Thus , the challenging issue of managing System Inertia and RoCoF is of utmost importance in order to secure future Malaysian electricity power grid against increased probability of partial system collapse .
One characteristic that variable renewable generation ( VG ) such as solar photovoltaic have in common is that their generation output is governed by atmospheric / climatic conditions and consequently difficult to predict over some time scales . Thus , large-scale penetration / integration of VG leads to increases in the variability and uncertainty in the system ’ s generation output , driving the need for greater flexibility . This is required in order to ensure the overall demandgeneration balance , at 50Hz system frequency , is maintained at all times .
In both technical policy papers published in the quarterly publications of The Ingenieur , Vol 60 & Vol 75 [ Ref . 5 , Ref . 6 ], this author has recommended that the Government design and shape its future long-term ( at least up to 2050 ) electricity generation energy mix with clear targets for each primary portfolio fuel based on the following key drivers :
● extent of concern about domestic energy security ;
● availability and price of ‘ legacy ’ indigenous natural gas for electricity generation ;
● extent of integration of renewable energy variable generation , particularly solar PV plants ;
● cost and availability of imported coal for electricity generation ;
● cost and availability of the nuclear option for electricity generation ; and
● environmental policy objectives expected over the next decade .
Each of these key drivers requires supportive policies and regulatory processes to enable appropriate commercial decisions to be taken in a prudent and timely manner .
4 . Renewable and Distributed Generation
Variable Generation Globally , Renewable Energy ( RE ) has experienced significant decline in costs , further driving the global push to decarbonise the electricity generation supply industry , as shown in Figure 16 .
Domestically , Solar PV is almost cost competitive with conventional fossil fuels , with grid parity expected by 2025 , as shown in Figure 17 .
According to the McKinsey Global Institute Report ( MGI ) [ Ref . 3 ], solar and wind power could represent 15 % to 16 % of global electricity generation in 2025 , up from only 2 % in 2013 . The incremental economic impact of this growth could be USD165 billion to USD275 billion annually by 2025 . Of this , USD145 billion to USD155 billion could be the direct value-added to the world economy from this power , less the cost of subsidies .
For Malaysia , solar power could generate enormous benefits for businesses that provide or consume energy , as well as consumers and society , but this would still require strong Government support , including green tax rebates . Greater demand for this variable solar photovoltaic generation could provide opportunities for technology providers and suppliers of ancillary equipment to manage the variability issue by providing that much-needed flexibility on the power system grid operation . Electricity utility companies could play a major role in the adoption of these Large-Scale Solar power plants by making some investments in battery energy storage systems to accommodate intermittent flows of solar power into their grids .
Also , distributed solar photovoltaic renewable energy generation – power / energy bought from local , small-scale operations or from commercial and residential users – could help defer investment in transmission and distribution infrastructure .
While the cost of solar PV cells and the overall cost of solar power generation have dropped
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