Ingenieur Vol. 75 ingenieur July 2018-FA | Page 51

demand and use it to support capacity at times of high demand. Today, about 3%-4% of the electricity that is produced by utilities worldwide is stored, almost all of it through a technique called pumped hydro-electric storage (PHES) which involves pumping water uphill during times of low demand and/or low cost and releasing it downstream to turn power-generating turbines during times of demand and high cost. Battery energy storage systems [BESS] in their various forms constitute the most widely known energy storage technology, which will impact future electricity grid infrastructure development and operation. Lithium ion (Li-ion) batteries are widely used in consumer electronic devices such as laptop PCs, as well as in electric and plug-in hybrid vehicles. According to [Ref. 5: Global lithium-ion battery market: Growth trends and application analysis, Malavika Tohani, Frost & Sullivan, Feb. 2013], the Li-ion battery market is expected to double in the coming years to US$24 billion in global revenue, and significant performance and cost improvements are also expected in Li-ion batteries in the coming decade. For example, prices for complete automotive Li-ion battery packs could fall from RM2000 – RM2400 per kWh today to about RM650 per kWh in 2025, while the life cycle could increase significantly at the same time, potentially making plug-in hybrid and electric vehicles cost competitive with traditional internal combustion engine vehicles on a total cost of ownership basis. For utility grid applications, the average cost of owning and operating Li-ion BESS could fall from about RM2000 per MWh [RM2 per kWh] to about RM400 per MWh [40sen per kWh] by 2025. This could make Li-ion BESS cost competitive for some electricity grid applications, such as for providing BESS-Solar PV hybrid distributed renewable energy, based on the levelised cost of electricity (LCOE), a standard measure of electricity costs. LCOE measures the cost of electricity generated by different sources accounting for present value payment stream of the total cost of capital, anticipated operating costs, fuel, and maintenance over a technology’s useful life and is very useful for comparing the prices of technologies with different operating characteristics. With growing electricity demand and top- level Governmental concerns over carbon dioxide emissions and climate change, there is growing national and international pressure for ‘green means’ of electricity production and usage. On a world-wide scale, 13 billion tonnes of CO2 are released annually from electricity generation and seven billion tonnes annually through transportation [Ref. 6: World Energy Outlook 2011, International Energy Agency, November 2011]. The electricity and transportation sectors are now more committed to add more sustainable energy sources and, in both sectors, these efforts rely on energy storage: For the electricity sector, BESS can help to: • ac c ommo date variable elec tricit y generation from renewable solar photovoltaic; • maintain capacity for peak demand; and • manage frequency regulation. For the transportation sector, advanced batteries make electric and partially electric vehicle adoption more competitive with petrol- engine vehicles. Grid-storage BESS Grid-storage BESS are set to play an increasingly important role in integrating solar photovoltaic renewable variable generation as part of the future Malaysian electricity grid infrastructure ‘fossil fuels-renewable energy mix’ portfolio. The main role of BESS will be to deal with peak demand capacity issues and as part of Smart Grid applications. BESS in Smart Grid applications can help with system frequency regulation and guaranteed peak power services. Grid-storage BESS enable peak load shifting, higher utilisation of existing grid infrastructure, efficient balancing of small fluctuations in power output, as well as providing temporary power in the event of outage. However, for these benefits to be realised, energy storage must be cost competitive with other methods of addressing these issues, such as gas turbine power generation used for peaking power applications and demand-side management for demand response applications (that is getting consumers and businesses to voluntarily reduce usage during peak demand 49