for 30 % to 70 % of their monthly bill ( McLaren et al . 2017 ). Hence , services that provide a backup system and reduce demand charges are one of the examples of stacked services . To conclude , the discussed applications are the up to date SLB applications that have been monetised properly in the regulated world of energy utilities . Thus , it can be concluded that there are still many potential SLB applications that are yet to be studied and monetised .
SAFETY
Figure 5 : SLB possible applications
distribution grid investment deferrals , energy arbitrage to integrate renewable energy as well as ancillary services . For behind-the-meter , grid stability is the most important element for consumers and data centres . This is because the business operating cost of consumers is greatly affected by their productivity . Some of them often turn to ESS as a solution to avoid power quality issues due to grid instability . Nowadays , on-site generators or lead-acid batteries have been replaced by LiBs as backup power . Since SLBs will only be used less than 1 % of the time in such applications , it will be providing energy to other services at the same . Also , these consumers who often face expensive monthly bills have been utilising SLB as an ESS to manage their peak load and reduce demand charges . It is worth noting that this maximum demand charge can account
Toxicity by the LiBs can be categorised into
CO 2 emission due to the use of conventional electricity to manufacture the battery itself , and toxic emissions produced within the battery during thermal runaway . Manufacturing a 1kWh LiB requires 50-65kWh of electricity which if the source was a coal-fired power plant , is then equivalent to 55kg of CO 2 emission ( Davidsson Kurland 2019 ). In other words , producing 1kWh from coal-fired power plant is much cleaner than producing a 1kWh LiB . Hence , greener and more sustainable batteries which require less energy and produce less CO 2 during the manufacturing process are needed . For that reason , the selection of electrodes and electrolyte are an important factor to ensure a continuous supply of batteries to cater to the huge energy demand which is estimated to be 130,000TWh per year with CO 2 free by 2050 ( Larcher and Tarascon 2015 ). While the electrodes contain no toxic lead and cadmium , the electrolytes on the other hand do have toxicity issues . The use of lithium-based electrolytes which contain fluorine-based anions is hazardous ( Sun et al . 2016 ). Toxic emissions by the LiBs are dependent on the battery materials besides cell capacity and state of charge .
There have been many improvements to ensure that LiBs are safe , especially on the use of safer electrolyte materials , keeping the battery within the operating temperature by enhancing the cooling system and incorporating proper battery management systems to avoid overcharging . Hence , just like any other heat sensitive system , continuous temperature monitoring of the LiBs is crucial to ensure the safe operation of the battery pack .
73