Academic Journal of Science and Technology 
ISSN: 2771-3032 | Vol. 8, No. 1, 2023 

 

133 

Application	of	Underwater	Constant	Pressure	
Compressed	Air	Energy	Storage	Technology	in	The	
Direction	of	Hydrogen	Production	
Jinyang Chen1, a 

1Qinghai University, Qinghai, 810016, China 
a210805040106@qhu.edu.cn 

 

Abstract: With the growing global demand for renewable energy to cope with climate change and energy security issues, 
underwater compressed air energy storage technology has gradually attracted attention. At the same time, hydrogen production 
process, as an important support for green energy transition, is becoming one of the key links to achieve clean energy generation 
and storage. This paper aims to explore the connection between underwater compressed air energy storage technology and 
hydrogen production process, and put forward a device combining underwater compressed air energy storage and hydrogen 
production, so as to solve the problems of low efficiency and serious pollution in the traditional hydrogen production industry. 
In the past, scholars focused on microcosmic research in the direction of hydrogen production, and tended to the direction of 
catalyst. Based on this, this paper will study the case of underwater compressed air energy storage device, and conceive a new 
hydrogen production device to promote the collaborative application of sustainable energy and improve the integration efficiency 
and reliability of energy system. 

Keywords: Underwater compressed air energy storage, Hydrogen production, Renewable energy, Energy conversion, 
Environmental friendliness. 

 

1. Research Background 

1.1. Background and significance 
Wind energy has unpredictable volatility and variability, 

and it is difficult to artificially interfere with the power output 
of wind farms.  

Therefore, direct connection of large-scale wind power to 
the power grid may have a significant impact on power quality, 
such as the fluctuation of power grid frequency and voltage, 
and the adverse impact on harmonics. Compared with 
traditional compensation and adjustment devices, such as 
static reactive compensation devices and static synchronous 
compensators, energy storage technology has faster response 
ability. Traditional devices are usually characterized by 
reliable, stable and convenient maintenance, but energy 
storage technology can respond more quickly. To deal with 
the problem of wind power grid connection, we usually use 
traditional compensation adjustment devices and energy 
storage technology. Underwater compressed air energy 
storage technology is charged at load trough and discharged 
at peak.  

The round-trip efficiency of the energy storage system 
under real and inevitable working conditions is 64.1 % and 
87.9 % respectively. It provides a potential solution to solve 
the fluctuation of renewable energy and energy storage 
demand. The underwater compressed air energy storage 
system can realize the storage of high energy density in the 
Marine environment, and provides long-term energy supply, 
which is suitable for the balance of seasonal energy demand. 
However, how to better integrate the underwater compressed 
air energy storage system to meet the growing demand for 
clean energy still needs in-depth research. The role of 
hydrogen production technology in green energy 
transformation is becoming increasingly prominent. 
Hydrogen energy can be divided into three categories: gray 

hydrogen, blue hydrogen and green hydrogen.  
Among them, ash hydrogen is produced by burning fossil 

fuels, and blue hydrogen is made by a series of natural gas 
reactions. Unlike this, green hydrogen comes from renewable 
energy sources, such as electrolytic water making hydrogen 
and solar pyrolysis water making hydrogen making, 
environmentally friendly. In these three types, gray hydrogen 
is not desirable, blue hydrogen is acceptable under certain 
circumstances, and green hydrogen is considered to be the 
optimal choice for the utilization of hydrogen energy, because 
it conforms to the direction of sustainable development. 
Using renewable energy to produce hydrogen not only 
produces green hydrogen, but also helps balance the energy 
system and improve energy utilization efficiency. The 
development of hydrogen production technology enables the 
excess energy of hydropower, solar and other energy sources 
to be converted into hydrogen for storage, and then supplied 
to the demand when the energy is insufficient. However, there 
are still some problems that need to be further studied how to 
organically combine hydrogen production technology with 
underwater compressed air energy storage technology to 
realize energy synergy.  

1.2. Research objective and method 
This study aims to explore the relationship between 

underwater compressed air energy storage technology and 
hydrogen production technology, focusing on the technical 
integration, environmental benefits, economic feasibility and 
practical application cases of the two.  

This paper takes the knowledge network and nature 
database as the source of literature, and fully collects the 
corresponding literature data. It mainly involves the theory of 
proton exchange membrane (PEM) technology, the research 
status of hydrogen production of seawater, the combination of 
underwater constant pressure compression air energy storage 



 

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technology and the prospect of hydrogen production trend of 
seawater. The study and thinking of the above studies and 
references are the theoretical basis for the follow-up research 
and discussion of this paper. Under the condition of this theory, 
this paper puts forward a device combining underwater 
compressed air energy storage with hydrogen production to 
solve the traditional system. 

2. Literature Review 

2.1. Review of underwater constant pressure 
compressed air energy storage technology 

Underwater Compressed Air Energy Storage (UW-CAES) 
technology, as an energy storage solution, has high efficiency 
energy density and long-term storage capacity, and has 
attracted wide attention in the energy field. UW-CAES 
system achieves energy conversion by compressing air from 
the surface and storing it underwater, and then releasing the 
gas to drive a turbine to generate electricity. 

Compared with traditional compressed air energy storage 
systems, the underwater constant pressure compressed air 
energy storage technology has a higher energy density and a 
longer storage period. The static pressure characteristic of 
water is an excellent condition for realizing isobaric 
compression. The use of isobaric compression method to deal 
with gas can avoid the drawbacks of decreasing output power 
with the release of gas in the isobaric process, low efficiency 
of expansion machine, long-term working in non-rated 
conditions [1], and is suitable for the adjustment of seasonal 
energy fluctuations. 

In addition, the existing scholars have studied the 
characteristics and performance factors of the system, 
providing strong support for further optimization of the 
technology [1]. 

2.2. Overview of hydrogen production process 
As a key link of green hydrogen production, hydrogen 

production process has become the focus of renewable energy 
transformation. According to literature review [2], the use of 
electrolytic water, biological method, thermal chemical 
method and other methods of hydrogen production can 
convert excess renewable energy into hydrogen storage, so as 
to achieve sustainable energy utilization. There are three main 
ways of electrolytic water hydrogen production, which are 
alkaline water electrolyzer (AWE), PEM electrolytic water 
hydrogen production, and solid oxide electrolytic water 
hydrogen production (SOE)[3]. The seawater hydrogen 
production process can not only provide green hydrogen, but 
also help balance the power grid and increase the flexibility of 
the energy system when there is an energy surplus [4]. 
However, aspects such as the economy, energy efficiency and 
hydrogen storage technology of hydrogen production process 
still need to be further studied and improved. 

2.3. Connection between underwater 
compressed air energy storage and 
hydrogen production process 

Underwater compressed air energy storage technology and 
hydrogen production process are both areas of high attention, 
with their potential in energy storage and clean energy 
production, respectively. Unlike chemical and biological 
hydrogen production,this new energy hydrogen production 
technology can achieve zero emissions and produce hydrogen 
with high purity and almost no debris [5]. More striking, 

however, is the potential for profound technological 
integration between the two technologies. We can explore the 
relationship between underwater compressed air energy 
storage technology and hydrogen production process, 
revealing its synergies and future development prospects. The 
combination of underwater compressed air energy storage 
technology and hydrogen production process can realize the 
integration of multiple energy sources and improve the 
flexibility of the system. Underwater compressed air energy 
storage technology can convert electrical energy into gas 
energy when there is an oversupply of renewable energy [6], 
while the hydrogen production process can convert electrical 
energy into hydrogen for storage. This integration can balance 
the volatility of renewable energy while releasing stored 
energy at times of peak energy demand for a smooth supply 
of energy [7]. 

As another promising technology, underwater compressed 
air energy storage, combined with hydrogen production 
processes, offers broad prospects for the development of 
hydrogen energy.  

Underwater compressed air energy storage can not only 
solve the problem of volatility of renewable energy, but also 
provide a stable power supply for the hydrogen production 
process. Such integration can not only improve energy 
efficiency, but also help reduce the cost of hydrogen 
production and promote the sustainable development of 
hydrogen energy. 

3. Technology Integration and 
Optimization 

3.1. System design: Integrated design scheme 
of underwater compressed air energy 
storage system and hydrogen production 
process 

As shown in Figure 1, the operation process of this 
integration solution is as follows: Based on the principle of 
seawater hydrogen production, hydrogen and oxygen are 
produced by the electrolysis of seawater by the power supply, 
and the hydrogen is pressed into the compressor for storage. 
The oxygen generated by electrolysis is stored by the principle 
of underwater constant pressure compressed air energy 
storage, and then pressed into the turbine by the submarine 
pressure to generate electricity and current. At the same time, 
the off-current generated by the seaside wind power 
generation and the current generated by the turbine are input 
into the power supply together. Forming a semi-closed closed 
loop. 

 

  
Figure 1.  



 

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3.2. Control strategy: Optimize the control 
method toachieve energy conversion and 
supply and demand matching. 

Underwater compressed air energy storage technology has 
the potential to store and release energy in the power system 
[8,9].The advantages of this technology lie in its high energy 
density and long storage cycle. However, there are problems of 
energy loss and system efficiency in the energy storage 
process, which need to be solved by optimizing control 
strategies. On the other hand, seawater hydrogen production 
technology is able to use the water in seawater to decompose 
to produce hydrogen, providing a sustainable path for 
hydrogen energy supply. However, the energy consumption of 
hydrogen production from seawater electrolysis is closely 
related to the supply status of the power system and needs to 
be optimally controlled according to the availability of 
renewable energy sources.  

Therefore, during periods of oversupply of electricity, 
excess electrical energy can be used for electrolysis of 
seawater for hydrogen production to convert electrical energy 
into hydrogen energy. This can increase the utilization rate of 
renewable energy and lay the foundation for a future hydrogen 
energy economy. Through a comprehensive control strategy, 
the collaborative operation of electrolytic hydrogen 
production and compressed energy storage can be achieved. 
According to the power demand of this system, the operation 
of the two technologies is dynamically adjusted [10] to 
achieve the optimal distribution of energy.  

The combined application of underwater compressed air 
energy storage technology and seawater hydrogen production 
technology has the potential to bring innovative solutions to 
the clean energy sector. By optimizing control strategies, 
achieving energy conversion and matching supply and 
demand, energy utilization efficiency and sustainability can 
be improved. 

3.3. Energy matching: Study how the 
underwater compressed air energy storage 
system and hydrogen production process 
complement each other to cope with 
different energy fluctuations. 

The challenge of energy transition requires us to seek 
innovative ways to deal with the volatility of different energy 
sources to achieve efficient conversion and storage of energy. 
Underwater compressed air energy storage and seawater 
hydrogen production technologies, as two important clean 
energy solutions, can complement each other to achieve a 
balanced energy match [11-13]. With the development of 
intelligent control and big data technology, underwater 
compressed air energy storage and seawater hydrogen 
production technology can be more closely integrated with the 
power system. This will help predict energy demand and 
supply more precisely, enabling more efficient energy 
matching. This integration not only creates new possibilities 
at the technical level [14,15], but also provides new directions 
for the sustainable development of energy systems in the 
future. 

4. Technological Innovation 

4.1. Technological innovation direction 
technical innovation can focus on improving the reliability 

and stability of energy storage system, and realize long-term 
energy storage and release through more advanced control 
strategies and material technology. Innovation and 
improvement of gas storage storage design, material 
innovation and system engineering, improve energy storage 
density and compression ratio, integrate it with hydrogen 
energy, improve electrolytic efficiency, and reduce hydrogen 
production energy consumption. The research and 
development of efficient electrolytic equipment, electrolytic 
catalyst and optimization process will help improve hydrogen 
production efficiency and reduce production cost. Building an 
intelligent energy system can achieve the balance of energy 
supply and demand, and will help the sustainable 
development of the integration scheme. 

4.2. Intelligent application:  
Real-time monitoring and adjustment of the electrolytic 

process of hydrogen production in seawater by using 
intelligent control system to optimize the electrolytic 
efficiency, improve the hydrogen production, and achieve the 
best energy utilization. Intelligent control can adjust the time 
and yield of hydrogen production according to energy supply 
and grid demand, and realize flexible production plan. 
Combined with big data analysis and prediction algorithm, 
accurate prediction of hydrogen production process and 
energy supply can be realized, so as to make more accurate 
operational decisions.  

Through data analysis, production plans can be optimized, 
production efficiency can be improved, and energy waste can 
be reduced. The application of automation technology to 
Marine hydrogen production equipment can realize the 
automatic control and monitoring of production process, 
reduce human intervention, improve production efficiency 
and stability. In addition, the intelligent maintenance system 
can monitor the state of the equipment in real time, predict the 
fault and carry out timely maintenance, and reduce the 
downtime. Intelligent prediction, optimization and control of 
hydrogen production process can be realized by using 
artificial intelligence technology.  

Through machine learning and deep learning algorithm, the 
complex reaction mechanism of hydrogen production in 
seawater can be analyzed, and the operation parameters can 
be optimized, so as to improve the production efficiency and 
hydrogen production quality. 

4.3. Energy market participation: 
From the perspective of theoretical significance, research 

on the promotion of underwater compressed air energy 
storage technology in the hydrogen production market will 
provide a beneficial supplement for the traditional energy 
utilization mode and the theoretical system of the 
development of the existing new energy production industry.  

In theory, the enrichment and expansion will provide the 
government, industry and enterprises with the key planning 
of new energy hydrogen production projects, the integration 
and cooperation development of new energy hydrogen 
production industry with other energy fields, and the 
formulation of new energy hydrogen production policy. In 
practical significance, with the accumulation of 
demonstration experience of new energy hydrogen 
production projects in China, the promotion of these projects 
has become an inevitable trend.  

Under the background of energy transformation, how to 
maximize the competitive advantages of new energy 



 

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hydrogen production projects to meet the green development 
needs of the energy industry and optimize the energy structure, 
In addition, finding appropriate strategies in the fields of new 
energy hydrogen production and related policies will help 
improve the comprehensive competitiveness of the new 
energy hydrogen production industry, promote the 
development requirements of its internal and external 
environment, and accelerate the promotion of hydrogen 
production in underwater compressed air energy storage. 
Ensure the green transformation and upgrading of hydrogen 
production industry. 

5. Conclusion 
Hydrogen production using underwater compressed air 

energy storage is a potential technology that can promote the 
large-scale application of renewable energy and energy 
transformation. Therefore, the connection between underwater 
compressed air energy storage technology and hydrogen 
production process is of great significance for promoting the 
integration and application of renewable energy. A new type 
of device proposed in this study explores this connection in 
depth, providing a new perspective and method for clean 
energy generation and storage. 

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