Let's talk about energy storage with everyone.
Behind the global power supply shortage, it actually highlights an unresolved weakness in the power system, which is energy storage technology.
The underdeveloped energy storage technology is equivalent to the lack of inventory as a buffer for the power product. Any significant fluctuation in supply and demand will have an impact on the power system. Especially, as the global energy structure shifts from traditional energy to new energy, this weakness will become increasingly prominent.
According to the current global electricity consumption, only 40000 square kilometers of solar panels are enough to supply global electricity. 40000 square kilometers may sound intimidating, but in fact, it is only 1/40 of the area of Xinjiang Uyghur Autonomous Region.
The main reason why human electricity cannot rely solely on solar energy is that energy storage technology cannot keep up.
01
Four technical directions for energy storage
From the photovoltaic industry, you probably brush Tiktok every day or every week occasionally, use VPN to browse Facebook, Ins, oil pipes, or chat with overseas customers with whatapp.
The key to achieving carbon neutrality in China by 2060 is also energy storage technology. In the context of new energy and carbon neutrality, energy storage technology is a field that must be focused on.
In July 2022, the National Development and Reform Commission of China issued the "Guiding Opinions on Accelerating the Development of New Energy Storage", which clearly stated that by 2025, the installed capacity of new energy storage should reach over 30 million kilowatts, which is nearly 10 times the current installed capacity. It will grow nine times in four years.
The future energy storage technology may mainly focus on electrochemical energy storage.
There are four main directions for energy storage technology: pumped storage, compressed air energy storage, flywheel energy storage, and electrochemical energy storage.
Pumped storage is the process of pumping water to a high place and generating hydroelectric power when needed. This energy storage method has a large capacity and a high number of cycles, but it has high requirements for terrain and limited application scenarios.
Compressed air energy storage and flywheel energy storage have relatively low energy and power, and have not yet entered commercial applications.
Electrochemical energy storage is a variety of battery technologies represented by lithium batteries, with a wide range of application scenarios. It is considered the mainstream of future energy storage technology, accounting for over 90% of all energy storage.
The energy storage field is divided into two major areas:
One is battery manufacturers like Ningde Times;
The second is the integrator of battery systems, which integrates battery packs, security and fire protection systems, converter systems, energy management systems, and more. There are currently Huawei, Sunshine Power, and others in this field.
At present, the national standards for the energy storage industry are not yet systematic, and most of them are in the stage of soliciting opinions.
There may be a shared energy storage model in the future.
According to the regulations of the National Development and Reform Commission, new energy power generation projects must be equipped with no less than 10% of energy storage capacity to ensure the stability of online electricity. However, if each new energy station needs to build its own 10% energy storage capacity, it is also quite troublesome. So, there is a possibility of a business model in the future, which is to establish and share energy storage power stations. Each new energy station in this area pays for it and uses its electricity for peak shaving and frequency regulation.
In the field of energy storage, whether it is battery manufacturing or integration capabilities, China will soon be at the forefront of the world.
What is an energy storage power station used for? It can serve as a backup power source for cities and serve as emergency power supply for hospitals, emergency departments, communication facilities, and rescue facilities in the event of a power grid failure.
In addition, energy storage power stations can also be used as black start power sources, that is, when the power grid malfunctions, they can be used to drive thermal power units in the grid and restore power supply.
02
Types of new energy storage batteries
At present, there are three main technological routes in the new energy battery race: lithium-ion batteries, sodium ion batteries, and hydrogen fuel cells.
Tesla's 4680 lithium-ion battery;
Sodium ion batteries from the Ningde era;
Hydrogen fuel cells and so on.
*Recently, vanadium batteries have emerged. Not only have projects been implemented, but the "14th Five Year Plan for the Development of New Energy Storage" and "Technology Support for Carbon Peak and Carbon Neutralization Implementation Plan" released in 2022 also mention vanadium batteries. Since July, the capital market has also been continuously heating up, with vanadium battery concept stocks collectively rising.
In October 2022, the upcoming Dalian energy storage power station will use a new technology, all vanadium flow batteries, which can also be directly referred to as vanadium batteries. Vanadium is a rare metal. The principle of all vanadium flow batteries is that vanadium ions with different valence states undergo redox reactions in the electrolyte, thereby achieving charge and discharge. This Dalian energy storage power station is currently the largest all vanadium flow battery energy storage power station in the world.
Vanadium batteries were commercially applied in 1993, while lithium batteries were commercialized in 1991. Although they started almost simultaneously, the subsequent explosive battery application scenarios happened to favor lithium batteries rather than vanadium batteries.
The major application scenarios of battery technology in the past 30 years are electronic devices and electric vehicles, which require batteries to be as small as possible. This is the strength of lithium batteries, but it is precisely the fatal weakness of vanadium batteries.
The battery energy of lithium batteries is mainly stored in solid-state electrical materials, while the battery energy of vanadium batteries is directly stored in canned electrolytes. Liquids themselves occupy more space than solids, and in addition, there are two external structures of the electrolyte, a transport pump and an electric stack, which can be combined to complete charging and discharging. Therefore, the bulk of vanadium batteries is particularly large.
The solubility of vanadium ions is relatively low, and the electrolyte cannot reach the desired high concentration.
The energy density of lithium batteries is currently between 80-300 watt hours per kilogram, while the energy density of vanadium batteries is only 12-40 watt hours per kilogram. To store the same amount of electricity, the volume of vanadium batteries needs to be five times that of lithium batteries.
With the advent of the energy storage era, the demand for energy storage has exploded, and energy storage power stations are being built in various regions. There is plenty of space in energy storage power stations, so the large volume of vanadium batteries is not a problem.
Advantages of vanadium batteries:
Firstly, safety.
Excessive charging and discharging, short circuit, and squeezing of lithium batteries can all cause overheating and accidents.
Vanadium batteries, both positive and negative electrolytes, are non flammable and operate at room temperature and pressure without combustion or explosion.
Secondly, it has a long lifespan.
The charging and discharging times of lithium batteries are limited, usually between 1000 and 4500 times. During each charging and discharging process, in addition to chemical energy conversion, lithium batteries also undergo physical deformation. When the electrolyte completely becomes solid, the lithium battery becomes invalid.
Vanadium batteries do not undergo physical changes during use, and the loss of battery capacity is minimal. Even if the battery is used for too long and its performance decreases, it can still be restored by repairing the activity of the electrolyte.
Vanadium batteries often have a lifespan of over 10 years and can be charged and discharged more than 15000 times, which is more than three times that of lithium batteries.
At present, the initial installation cost of vanadium batteries is twice that of lithium batteries, but in terms of the entire life cycle, the cost of vanadium batteries is already lower than that of lithium batteries.
Thirdly, it is easy to expand.
The battery pack of lithium batteries consists of a large number of individual batteries. As charging and discharging progress, the internal resistance, state of charge, temperature, and other factors of each battery will change to varying degrees. The situation of each battery is different, which poses high technical requirements for large-scale deployment. The electrolyte and stack of vanadium batteries are independent of each other, and although they occupy a relatively large space, this decoupling design is very suitable for the development of large-scale battery packs.
As long as the electrolyte is added, the battery capacity can be increased, and increasing the stack can increase the output power.
Vanadium batteries can easily synthesize large-scale battery packs, storing up to 100000 kilowatt hours of electricity.
Fourthly, China has a large reserve of raw materials that are independently controllable.
More than half of the global lithium resources are located in the lithium triangle region of South America, and China's lithium energy storage accounts for only 7% of the global total reserves, highly dependent on imports.
At present, the global proven vanadium ore reserves are 24 million tons, of which China's reserves are 9.5 million tons, accounting for 40%, ranking first in the world.
High safety, long lifespan, easy expansion, and large storage capacity, vanadium batteries outperform lithium batteries in energy storage scenarios.