Fueling ships is generally an ordinary operation,but recently,a container vessel operated by the global shipping giant Maersk drew international attention while refueling at the Yangshan port in Shanghai.This vessel was not refueled with conventional fuel; it was filled with “green methanol,” marking a significant milestone as this was China’s first large-scale simultaneous refueling of a methanol-powered vessel.Shanghai port has now joined the ranks of the few major ports worldwide capable of this operation.

“Green methanol” is a type of hydrogen-based energy.With the gradual integration of hydrogen fuel cell vehicles into everyday use,public awareness of hydrogen energy has increased—yet knowledge regarding hydrogen-based energy remains limited.To put it simply,hydrogen-based energy refers to secondary energy that predominantly utilizes hydrogen as the main carrier.The production process usually starts with green hydrogen derived from electrolyzing water using renewable energy,which is then utilized as a key raw material through a series of chemical reactions to produce other forms of green energy,such as green ammonia,green methanol,green aviation fuel,and green methane.Unlike carbon-based energy sources like coal and oil,hydrogen-based energy presents a distinct alternative that is not only environmentally friendly but also holds broad applications for the future.In light of the accelerating global transition to green and low-carbon initiatives,hydrogen-based energy markets are poised for rapid growth.

The momentum surrounding hydrogen-based energy is rising steadily.In April 2023,China Shipbuilding Group and France's CMA CGM signed a collaboration agreement in Beijing that set a new record for the largest single contract in China's shipbuilding industry for container vessels.Among these,twelve vessels are categorized as large methanol dual-fuel container ships capable of nearly zero emissions across their entire voyage.Fast forward to November 2023,Maersk entered into a commercially viable long-term green methanol procurement agreement with Goldwind Technology,aimed at supporting the low-carbon operations of the first twelve large dual-fuel methanol ships.This event marked the inaugural large-scale procurement agreement for green methanol within the global shipping industry.In March 2024,the Port of Singapore successfully completed the world's first bunkering operation of ammonia fuel for ships.

One might wonder why hydrogen energy is transformed into hydrogen-based energy for usage instead of being utilized directly,as this could seem redundant.The answer lies in the challenges associated with hydrogen storage and transportation.Hydrogen,as a widely available clean and low-carbon secondary energy source,holds significant strategic importance in national energy systems and industrial developments,acting as a key vehicle for achieving green and low-carbon growth at energy-consuming endpoints.However,hydrogen comes with its own set of challenges: firstly,it is the lightest gas known,resulting in a relatively low energy density per unit volume; secondly,its liquefaction demands extremely low temperatures,leading to high energy costs and significant evaporation losses; and thirdly,hydrogen atoms,owing to their small radius,can permeate even thick steel at high temperatures and pressures,making them reactive,flammable,and in some cases,explosive,which raises stringent safety requirements for storage and transport.These issues hinder the large-scale and cost-effective long-distance transport of hydrogen energy.

In contrast,hydrogen-based energies like green ammonia,green methanol,and green aviation fuel boast lower storage and transportation costs and enhanced safety while benefiting from established downstream markets and business models.They can be extensively utilized as maritime fuel,in aviation,and in coal power mixed with ammonia,making them favorable for the current widespread adoption of hydrogen energy.Take green ammonia as an illustration: its liquid form exhibits higher volumetric energy density compared to liquid hydrogen,is easier to liquefy,and possesses a distinct odor,which can provide early warnings of potential leaks.Moreover,ammonia has been industrially produced and applied for over a century,resulting in a well-developed technological framework and infrastructure for storage and transport.Because of these advantageous properties,the world is now entering into a “Hydrogen 2.0” era in which the hydrogen energy sector is evolving towards “pan-hydrogen” energies such as green ammonia and green methanol.

When viewed from a long-term perspective,the environmental and economic value of hydrogen-based energy is incredibly promising.According to data from the Hydropower and Water Resources Planning and Design Institute,the current unit energy costs for terminal green ammonia and green methanol are approximately 0.19 RMB per megajoule and 0.23 RMB per megajoule respectively,as compared to petrol,which is approximately 0.26 RMB per megajoule.Therefore,alcohol (ammonia) as fuel has already gained a competitive edge over petrol.Looking ahead,the terminal utilization price for green hydrogen is projected to drop to below 25 RMB per kilogram,with unit energy costs for terminal green ammonia and green methanol potentially decreasing to 0.09 RMB per megajoule and 0.10 RMB per megajoule respectively.

Despite the promising outlook,there are still several challenges facing the development of hydrogen-based energy in China today.On one hand,the lack of a national-level certification standard system for green hydrogen-based energy is detrimental,as it hampers the healthy growth of related industrial chains and inhibits international trade collaborations.It is crucial to establish a comprehensive set of certification standards for green hydrogen-based energy that aligns with domestic conditions while being connected with international standards to promote green value certification across the entire hydrogen energy industrial chain.On the other hand,the current market for green hydrogen-based energy products in China is heavily concentrated overseas,which poses risks to the stable operation of the industrial chain.When production capacity reaches a feasible scale,there is a need for greater policy support for downstream applications such as transportation,chemicals,and thermal power,which would help unlock the domestic market and enhance the industrial chain's agency.

In conclusion,green hydrogen-based energy represents a forward-looking and strategic development direction in clean energy technology,serving as an effective medium for the interconnection between new power systems and resource systems.It is expected to play a crucial role as a linking element in China's emerging energy system.By adopting an approach that emphasizes trial and proven effectiveness while gradually promoting broader adoption,China aims to establish a hydrogen-based energy production and consumption system that caters to its national conditions.