INGENIEUR
Frequency Regulation When generation and demand are out of balance , the system frequency deviates from its 50Hz set point . Significant demand increases cause system frequency to drop and voltage to sag . Similarly , frequency increases are caused by loss of demand . Conventional power plants such as gas or coal- fired provide their own frequency regulation — a constant flow — by setting aside a portion of generating capacity ( typically 1 to 4 %) that can be ramped up to regulate frequency . By committing to reserve a portion of capacity in this way , utilities limit their output , losing some production efficiency .
Today , BESS are already competitive in the frequency regulation market where they are permitted by regulations which require reserve generating capacity to fulfil this role . BESS will become more competitive as prices decline . In this context , the potential economic impact of energy storage on frequency regulation for utilities worldwide can run into billions of dollars annually , assuming that BESS could replace all of the 4 % of generation capacity set aside for frequency regulation by conventional plants .
Peak Load Shifting To meet peak demand ( when generation prices are highest ), utilities can either build excess generation capacity or purchase electricity from other utilities or from specialised peaking plant suppliers . Energy storage could save costs by enabling utilities to avoid purchasing electricity at peak prices , and instead buying ( or generating ) when it is least expensive , regardless of when it will be used . The ability to store energy for use at a later time is also useful for integrating energy from solar photovoltaic generation into the electricity supply grid , due to the variable nature of this resource .
Implications on Electricity Supply Industry BESS solution providers need to gain the support of utility company leaders to plan and commit BESS for grid utility applications ( as discussed above ), as utilities tend to invest in 10-year development plan programmes . They also need to demonstrate that BESS work seamlessly with existing grid infrastructure and renewable solar photovoltaic systems , potentially requiring partnerships with companies with core competencies in software , process control systems , and grid integration . To get utilities to be comfortable with newer BESS technology , companies may also want to consider coinvesting in initial pilot projects .
Utilities face both risks and opportunities due to advanced battery energy storage . While energy storage may help improve the quality , reliability and efficiency of their electricity supply , other uses could affect overall demand as in the case of accelerated adoption of electric and hybrid vehicles . Peak load demand could grow quite substantially if charging is unconstrained ( that is , if most drivers come home after work and charge their vehicles when demand is highest ). This could place a new strain on peaking generation capacity , thus requiring new investment .
Future energy policy / regulation for electricity supply should include impact studies on energy storage technologies to determine whether there are incentives or disincentives for investment in grid storage and other relevant applications . The overall goal should be to ensure that energy storage is permitted to compete on an equal footing with other solutions . For example , gridstorage BESS should be allowed to compete with generation for frequency regulation and with peaking plants for peak load electricity supply . Introduction of renewable variable energy generation quotas ( solar photovoltaics ) could also promote investment in energy storage .
It is envisaged that by 2025 , the potential of energy storage for grid applications could become much more clearly defined in terms of advances in battery storage technology and cost . This market development will have longer-term potential ( beyond 2025 ) to disrupt electricity generation and distribution .
It is possible to envision a post-2025 scenario in which renewable solar photovoltaic generation , combined with cheap battery energy storage , and higher energy prices of conventional fossilfuels for electricity production , could eventually lead to significantly increased adoption of locallydistributed solar photovoltaic power generation . This could vastly alter the utility industry energy mix in terms of fossil-fuels ( coal and gas ) for electricity production , ushering in an era of localised microgrid of electricity / energy independence with drastically reduced emission levels .
66 VOL 87 JULY-SEPTEMBER 2021