Three questions about hydrogen energy

"In the future, we must not only develop hydrogen energy, but also develop a hydrogen economy
.
" At the Future Energy Conference, a sub-forum of the 2022 China International Petrochemical Conference held on November 16, participating experts, researchers and industry representatives warmly discussed the development opportunities brought by China's energy transition to the petrochemical industry and the development trend of future energy, and unanimously affirmed the important position of hydrogen energy in the future energy system, and put forward a technical roadmap
for the development of hydrogen energy.

Why hydrogen? An inevitable choice for energy conservation and emission reduction

Chen Guanfu, deputy general manager and deputy secretary of the Party Working Committee of PowerChina's overseas business department, deputy secretary of the Party Committee, director and general manager of PowerChina International Engineering Co.
, Ltd.
, said that among the emission reduction measures in various countries, the development of renewable energy has become a common choice, and the popularity of hydrogen energy has also increased
.

Why does hydrogen stand out from many renewable energy sources and become the protagonist of the energy of the future?

In this regard, Zeng Shaojun, professional vice president and secretary general of the New Energy Chamber of Commerce of the All-China Federation of Industry and Commerce, said that there are two main reasons
.
First of all, hydrogen energy is a zero-emission energy source, and the only product of combustion in oxygen is water; Secondly, hydrogen energy has a high energy density, and among all renewable energy sources, only hydrogen energy has an energy density that can compete with
traditional fossil energy.

"Hydrogen is not only the energy of the future, but also the energy
of the future.
" Zhang Zhen, director of the Hydrogen Energy Committee of the Electric Vehicle 100 Association and president of Shandong Hydrogen Ancient New Energy Technology Research Institute, pointed out that hydrogen energy is the hub
of the modern energy system.
As a strategic emerging industry, hydrogen energy can achieve integrated development with traditional industries and jointly promote green and high-quality development, such as energy, new materials, equipment manufacturing fields upstream of the industrial chain, green finance, carbon market, etc.
in the downstream of the industrial chain, can form a very good linkage, and will drive the scale
of 10 trillion-level emerging industries in the future.
It is expected that by 2050, China's demand for hydrogen energy will reach 60 million tons
.
For breaking through the bottleneck faced by the development of hydrogen energy, Liu Zhongyong, director of hydrogen energy business of China Large Industrial Business Group of Bureau Veritas, believes that first, it is necessary to be safe and reliable, and improve the safety of related equipment and facilities; The second is to have controllable quality, which determines how far the development of the hydrogen energy industry can go; Third, the cost is available, which is comparable to the price of traditional energy
.

How to get hydrogen? Development of bio-hydrogen production technology

Li Shizhong, professor of the Institute of Nuclear Energy and New Energy Technology of Tsinghua University and executive director of the Sino-US Biofuel Joint Research Center, said that at present, even the production cost of non-green hydrogen energy should reach 28~43 yuan / kg, and the storage and transportation cost is about
30 yuan / kg.
High costs and the extent to which infrastructure such as hydrogen refueling stations are equipped limit the development of
hydrogen energy.
He pointed out that China's biological hydrogen production technology is at the international leading level, if the straw returned to the field every year and the exploitable saline-alkali land can be used for the development of biological green hydrogen, it can not only effectively solve the problems of high cost, storage and transportation, high carbon emissions, but also conducive to the development of a hydrogen energy supply system
with Chinese characteristics.

"At present, biological hydrogen production mainly includes three methods of biomethane hydrogen production, biochar hydrogen production and bioethanol hydrogen production, and China has certain development advantages
in these three aspects.
" Li Shizhong said, first of all, the domestic biomethane hydrogen production technology has developed rapidly, according to the domestic biomethane production of 150 billion ~ 200 billion cubic meters / year, at least 60 million tons of green hydrogen
can be produced.
Secondly, in terms of the biochar hydrogen production industry chain, China's related technology has been at the international leading level, 1 ton of straw can produce 416 kg of paper, 80 kg of xylose, 30 kg of acetic acid and 360 kg of biochar
.
If this technology is used to use the 400 million tons of straw returned to the field every year for biocarbon hydrogen production, at least 40 million tons of green hydrogen
can be produced.
In addition, Tsinghua University has developed a nickel-based hydrotalcite catalyst, which not only solves the problem of high cost of precious metal catalyst, but also increases the conversion rate of bioethanol hydrogen production to more than 99%, and the hydrogen yield also reaches 90%.

More importantly, compared with hydrogen production by electrolysis of water, bioethanol hydrogen production saves the floor space of the equipment, and the cost per kilogram of hydrogen energy is about 32.
5 yuan, which is within the acceptable range
.
In the future, bioethanol hydrogen production equipment can be introduced into existing gas stations for direct use, which will help solve the infrastructure problems
in the process of hydrogen energy development.

"In addition to the existing large amount of straw, China also has 1.
5 billion mu of saline-alkali land, of which 500 million mu can be developed and utilized
.
If these lands are used to grow drought-tolerant and salinity-tolerant crops, the two problems
of 'rice bowl' and 'energy' can be solved at the same time.
Li Shizhong said
.

How to develop hydrogen energy? Achieve scale through upstream and downstream

"At present, from the perspective of technical indicators alone, China has basically reached the same level as the world's advanced level, but the entire engineering capability is still lacking, and more time is needed to verify the feasibility of
existing technologies.
" Zhang Zhen said
.

For how hydrogen energy can achieve large-scale and engineering development, many experts attending the meeting gave the same answer: build a green power-green hydrogen-green ammonia industry chain
.

"Ammonia is both a hydrogen energy carrier and a zero-carbon fuel, which is expected to play an important role in building a 'hydrogen energy society', and accelerating the development of a 'zero-carbon cycle' industrial chain integrating green ammonia industry, hydrogen energy industry and renewable energy industry is of great significance
to ensure national energy security and sustainable social and economic development.
" Li Bin, vice president of the China Petroleum and Chemical Industry Federation, said
.

"The development of green hydrogen is inseparable from green electricity, and the large-scale development and utilization of green hydrogen depends on the progress of renewable energy power generation technology, the improvement of system efficiency and the reduction of comprehensive costs
.
" The upstream and downstream of the hydrogen energy industry chain should work together to connect the green power-green hydrogen-storage and transportation-new application industry chain
.
Chen Guanfu said
.

Han Hongmei, deputy general manager of the investment division of China National Chemical Engineering Group Co.
, Ltd.
, said that green hydrogen is the most efficient in producing green ammonia, and green ammonia is also the most
efficient when reused as a chemical.
The downstream application scenarios of synthetic ammonia are rich and developed, the key is that most of the downstream application scenarios are the simultaneous transformation of nitrogen and hydrogen elements to the downstream, and there is a very large space
for development in building a green hydrogen and green ammonia industry chain.

"The key to doing a good job in this engineering scheme is to do a good job in two connections, one is the connection from electricity to hydrogen, and the other is the connection from hydrogen to ammonia, that is, there must be appropriate hydrogen production technology and ammonia synthesis equipment
.
" At the same time, auxiliary means should be taken to buffer the volatility of these two linkages, such as using large power grids and green power transactions as much as possible at the first junction to help maintain the balance and stability of the power grid; At the second joint, buffering can be achieved by setting up an intermediate tank to reduce the compounding fluctuation
of the ammonia unit.
In addition, in order to ensure the stable supply of electric energy, energy storage equipment
can also be appropriately added.
At present, the industrial model of green power-green hydrogen-green ammonia is still in the initial stage of development, and it is necessary to focus on establishing product labels
in the high-quality application field of green ammonia.
Han Hongmei suggested
.

Li Shizhong said that the yield of green ammonia from green hydrogen is basically the same as that of coal to synthetic ammonia, and about 1.
4 tons of raw materials produce 1 ton of products
.
At present, about 20 green power-green hydrogen-green ammonia projects are being planned and constructed around the world
.
In the future, relevant domestic enterprises should focus on the engineering of this industrial model
.