Guided by the”dual carbon”goal,the installed capacity of new energy power generation continues to increase.According to data released by the National Energy Administration,as of September 2023,the installed capacity of renewable energy in China is approximately 1.384 billion kilowatts,accounting for 49.6%of the total installed capacity in China,surpassing the installed capacity of thermal power.
However,the intermittency,volatility,randomness and other characteristics of new energy generation determine that it requires energy storage to absorb,frequency regulate,and peak shaving.When lithium batteries still occupy the dominant position in new energy storage,liquid flow batteries,as a new technological route,have gradually become a focus of attention in the capital market.
As a battery with greater safety and meeting long-term energy storage requirements,liquid flow batteries have entered a period of rapid development in production capacity and technology since 2023.According to incomplete statistics,from March to June alone,there were over 9 liquid flow battery production lines under construction and planned in China,with a total planned production capacity exceeding 8.2GW.
At the same time as the rapid development of production capacity,how to expand the application scale and reduce the electricity cost of new technologies has also become a topic of discussion in the industry and application end.Recently,Weijing Energy Storage Technology Co.,Ltd.(hereinafter referred to as”Weijing Energy Storage”)’s zinc iron flow battery”Super G Factory”was put into operation in Zhuhai.The reporter communicated with experts and enterprises on site to explore their solutions.
Liquid flow batteries provide greater safety
According to statistics from the High Tech Industry Research Institute(GGII),as of August 2023,24 provinces across the country have announced new energy storage installation targets for the 14th Five Year Plan period.The total planned new energy storage installation exceeds 67GW,which is more than twice the target set by the National Energy Administration to reach 30GW by 2025.Among them,policies issued by multiple provinces explicitly require that the peak shaving time for power side distribution and storage exceed 4 hours.
At present,in the field of energy storage batteries,the problems of short energy storage time,improved safety,and high electricity consumption cost of lithium batteries still need to be improved.The zinc iron flow battery has the characteristics of high safety,ultra long lifespan,and long-term energy storage of over 4 hours,”the person in charge of Weijing Energy Storage told reporters.
The lithium dendrites formed during the long-term charging and discharging process of lithium batteries can easily lead to short circuits and even cause cell explosions.If we want to increase the storage capacity,we must increase the lithium content,which brings higher safety risks.As a liquid based battery,zinc iron flow battery undergoes electrochemical reactions with two water-based electrolytes to achieve the effect of charging and discharging.The aqueous electrolyte is a safety barrier,”explained the person in charge.
The person in charge continued,”In terms of service life,the electrolyte of zinc iron flow batteries is also not prone to decay.During operation,simply online recovery is required,and the performance of the electrolyte can be reset.Moreover,the separation of electrochemical reactions and energy storage sites can be achieved,making the battery power and energy storage capacity design relatively independent,meeting the requirements of long-term energy storage
Regarding the shortcomings of liquid flow batteries,the founder of True Lithium Research,Moko,stated in an interview with reporters that liquid flow batteries have problems such as low energy density and low conversion efficiency.Moreover,the cost of lithium batteries is less than 10%of what it was 10 years ago,and the cost of liquid flow batteries should be higher than that of lithium batteries.
Energy storage still needs to reduce electricity costs
In addition to technology and security,in the industry’s view,one of the factors that constrain the large-scale application of energy storage is still cost.However,the cost of energy storage systems has already”rolled up”.Recently,the bid for the e-commerce procurement of the energy storage system of the National Power Investment Corporation in 2023 was opened,with a total procurement scale of 5.2GWh.Among the 0.5C system quotations,the lowest price has reached 0.644 yuan/Wh.
The reporter noticed that compared to lithium batteries,the cost of liquid flow batteries is still relatively high.Cost reduction requires large-scale application,and large-scale application also requires cost as a breakthrough point.
Weijing Energy Storage explained to reporters that the cost of new energy per kilowatt hour is the sum of power generation costs and consumption(energy storage)costs.The installation cost is only one of the components of energy storage and electricity cost,and can only reflect the purchase price of energy storage related equipment.
The specific cost of energy storage per kilowatt hour can be understood as the sum of installation cost,power loss cost,and operation and maintenance cost,divided by the total life cycle storage of electricity.Among them,the full life cycle storage capacity is also equal to the product of capacity and number of cycles.
Data shows that the number of cycles for lithium battery energy storage is usually only around 5000.In addition,lithium battery energy storage stations need to be equipped with fire-fighting facilities,which will further increase safety costs.Weijing Energy Storage stated that zinc iron liquid flow batteries can generally have a cycle count of over 30000 times,a service life of up to 25 years,and lower operation and maintenance costs throughout their entire life cycle.
At the production ceremony,Ge Qun,co-founder and chairman of Weijing Energy Storage,also stated that the current cost of coal-fired power generation is around 0.4 yuan per kilowatt hour,which has a significant advantage compared to new energy power generation combined with consumption costs.If the cost of energy storage per kilowatt hour is compressed to within 20%,the cost of all new energy per kilowatt hour in China will be cheaper than coal(power generation)in the next three years,which is also the company’s goal