Introduction

Climate change has emerged as a major global threat, especially owing to the rise of global average temperatures above pre-industrial levels due to increasing greenhouse gas (GHG) emissions. Consequently, countries around the world are actively pursuing policy and technological initiatives for achieving net-zero carbon emissions.

Net-zero refers to balancing GHG emission and absorption associated with human activities, which is considered necessary for limiting the increase in global average temperatures to well below 1.5°C above pre-industrial levels－a key goal of the Paris Agreement [an international agreement adopted by the Conference of the Parties to the United Nations Framework Convention on Climate Change (UNFCCC) at its 21st session in Paris, France, in December 2015, and officially entered into force on November 4, 2016 (UNFCCC, 2015)].

The importance of the agricultural sector in achieving global net-zero targets has been increasingly emphasized. Agriculture is widely recognized as one of the major sources of greenhouse gas (GHG) emissions. According to the UN Food and Agriculture Organization (FAO), the Land Use, Land-Use Change, and Forestry (LULUCF) sectors account for approximately 24% of global GHG emissions. Furthermore, FAO (2024) reports that the entire agrifood system—including agricultural production, food processing, distribution, consumption, and disposal—contributes about 29.7% of global GHG emissions, with a substantial share originating from agricultural activities.

In the shift to sustainable and environmentally friendly practices, changes in energy use have emerged as a key challenge. In recent years, hydrogen has gained attention as an alternative clean energy source. Its high energy density and easy storage and transportation capabilities make it suitable for decentralized energy supply systems in rural areas (IEA, 2023).

In this context, this study describes the domestic and international status of hydrogen energy technology in the agricultural sector, especially smart farms and tractors, and considers the applicability and limitations of hydrogen technology from various perspectives. The objectives of the study are as follows: First, we examined the status of global carbon neutrality policy and the need and role of hydrogen technology in agriculture. Second, we analyzed domestic and foreign cases of hydrogen technology applications in smart farms and agricultural machinery to verify their applicability. Finally, we considered the policy and technical prospects for expanding the adoption of hydrogen technology in the agricultural sector. By elucidating the potential of hydrogen energy-based technologies in the fields of carbon neutrality and sustainable agriculture, this study aimed to inform the development of efficient strategies for domestic agriculture and the direction of technological deployment.

Previous Research and Review

Global Carbon Neutrality Status

Global efforts toward net-zero carbon emissions have been collectively ramped up. In the wake of the 2015 Paris Agreement, various countries have adopted long-term low-carbon development strategies to limit the increase in global average temperature to well below 1.5°C above pre-industrial levels. As of 2024, more than 150 countries, accounting for about 90% of global GHG emissions, officially announced carbon neutrality targets. Among the major countries, the European Union (EU), United States, Japan, and Republic of Korea are targeting 2050, and China has declared that it would be carbon neutral by 2060. Table 1 shows the target year of carbon neutrality, 2030 GHG reduction targets, and hydrogen utilization in agriculture for major countries such as the Republic of Korea, United States, EU, China, and Japan. China has the highest GHG reduction target of 65% by 2030, followed by the EU (55%), US (50%), Japan (46%), and Republic of Korea (40%), showing spatial variation in reduction targets. The countries differ in terms of hydrogen utilization in the agricultural sector (smart farms), with Europe (Netherlands, Germany, etc.) introducing high levels of GHG reduction technologies to smart farms, and Japan actively expanding these technologies through government-led policies. The Republic of Korea, United States, and China are at the project level or early stages of research and development. In the agricultural sector (agricultural machinery), companies in the EU and US are developing prototype products. In the Republic of Korea, companies are only at an early stage of R&D. China has been conducting a government-backed pilot project to hydrogenate agricultural machinery. These observations highlight the widespread interest in the development of hydrogen technology for agriculture as an important strategy to achieve carbon neutrality and GHG reduction goals, but indicate clear differences in the level of technological development and policy support among countries.

However, there is a large gap between these goals and implementation. In a recent report, the UNEP projected a global average temperature increase of about 2.5°C by 2100 if current policy levels are maintained, warning that current policies are insufficient to achieve carbon neutrality (UNEP, 2024), which is closely associated with reliance on coal, especially in China and India, and the slow pace of renewable energy expansion.

The costs and technological challenges of the energy transition are also key issues. The International Energy Agency (IEA) estimates that approximately $4.5 trillion of investment will be required in the 2030s to achieve global carbon neutrality, emphasizing the need for financial support and technology transfer, especially to developing countries (IEA, 2023). Progress is being made in expanding EV, renewable energy, and carbon capture and storage (CCS) technologies, but commercialization and affordability remain limited. In particular, rare-earth resources for battery production and recycling are a major barrier to technology diffusion.

In the future, the active participation of the private sector as well as policy coordination among countries will become more important. According to the IEA (2023), the introduction of the EU’s Carbon Border Adjustment Mechanism (CBAM), increased environmental, social, and governance (ESG) investments, and the demand for carbon reduction at the global supply chain level drive the private sector’s response to carbon neutrality. Consequently, the roles of corporations and financial institutions have been increasingly strengthened, though building a sustainable financial system emerges as an important challenge. Carbon market mechanisms play an increasing role in international cooperation. Emissions trading schemes (ETS) and international carbon markets can be used to promote the efficiency and cost-sharing of emissions reductions among countries. International climate negotiations continue to center on financial support for developing countries and increased responsibility for developed countries. In the long term, the development of innovative technologies such as hydrogen energy, ammonia fuels, and green hydrogen production, as well as low-carbon industrial transformation and infrastructure expansion will be essential. Ultimately, achieving global carbon neutrality will be possible through a balanced approach across four pillars: technological innovation, policy coordination, private sector participation, and sustainable financial management (IEA, 2023).

Recently, hydrogen production and utilization technologies have gained attention in the field of carbon neutrality. According to Bhuiyan and Siddique (2025), hydrogen production methods are broadly categorized into gray, blue, and green hydrogen. Gray hydrogen is mainly produced through steam methane reforming (SMR) utilizing natural gas, which is a low-cost process but has limitations in terms of environmental sustainability due to carbon dioxide emissions. Blue hydrogen seeks to mitigate the environmental impact of SMR through carbon dioxide CCS. Although the technology has been maturing, some challenges include CCS infrastructure and economic viability. Finally, green hydrogen is produced through electrolysis using renewable energy sources such as solar or wind, and is the most environmentally friendly, with virtually no carbon dioxide emissions. However, the production cost is relatively high, and there are many technical challenges such as the efficiency and durability of the electrolysis device, which limits full-scale commercialization.

Green hydrogen production using renewable energy enables a sustainable energy transition with minimal carbon emissions. A popular approach is to utilize the surplus electricity from volatile renewable energy sources such as solar and wind to produce hydrogen, which is stored for long periods and converted to electricity via fuel cells (Sadeq et al., 2024). This represents a key strategy for building a stable energy system while overcoming the intermittency and variability of renewable energy. In particular, solid oxide electrolysis cells are gaining attention due to their high efficiency and environmental friendliness (Gaikwad et al., 2023). This technology can be utilized to effectively convert variable renewable energy via hydrogen fuel cells. In an operational study integrating a renewable wind power system with a hydrogen production plant, Wade et al. (2025) analyzed the optimal ratio of hydrogen production equipment to wind power capacity in a commercial greenhouse and demonstrated the economic viability of hydrogen production. Such an integrated system of hydrogen production, storage, and utilization could be applied to agriculture, transportation, and industry and play a key role in achieving carbon neutrality.

Carbon Neutrality Status in South Korea

Since the signing of the Paris Agreement in 2015, the Republic of Korea has set a net-zero carbon goal for which it has been steadily laying the institutional foundation (UNFCCC, 2015). The “FRAMEWORK ACT ON CARBON NEUTRALITY AND GREEN GROWTH FOR COPING WITH CLIMATE CRISIS” (hereinafter referred to as the “Framework Act on Carbon Neutrality”), enacted in 2021, clearly stipulates climate action at the national level by legislating a 40% reduction in GHG emissions by 2030 compared to 2018 levels, and realizing carbon neutrality by 2050.

The government plans to increase the proportion of renewable energy in total electricity generation to more than 30% by 2030 through its renewable energy-oriented energy transition policy. In addition, the government has been operating an effective carbon pricing system by strengthening the ETS, and has been actively supporting investment in eco-friendly facilities in energy-intensive industries such as steel and chemicals. In the transportation sector, the government has been building charging infrastructure and supporting policies to expand the use of electric and hydrogen vehicles, aiming to supply 3 million electric vehicles and 850,000 hydrogen vehicles by 2030. In addition, the government has been developing carbon capture, utilization, and storage (CCUS) technology and establishing a hydrogen economy roadmap to transform domestic industries based on clean energy practices. The private sector has also made various efforts. Major conglomerates such as Samsung Electronics, SK Group, Hyundai Motor, and POSCO have voluntarily established and are implementing carbon neutrality strategies by expanding the use of renewable energy, improving energy efficiency in manufacturing processes, and introducing hydrogen technology (IEA, 2023).

There are a number of real-world challenges on the path to carbon neutrality in the Republic of Korea. The expansion of renewable energy generation facilities has lagged behind due to a lack of public acceptance and siting restrictions, while low-carbon transformation of energy-intensive industries such as steel and chemicals is limited by high investment costs and technical difficulties. In addition, low levels of implementation are observed across companies, and the price stability of ETSs and facilitation of trading remain poor. Moreover, small and medium-sized enterprises (SMEs) tend to be marginalized from the policy due to lack of manpower and funding.

The Republic of Korea’s ability to achieve carbon neutrality will depend on consistent policy promotion by the government, technological innovation by the private sector, and long-term sustainable investment. This will require support specific to various industries, including SMEs, and a system design that harmonizes regulations and incentives.

Current Status of Hydrogen Energy Utilization in Agriculture

The Korean smart farm sector is a key initiative in sustainable development and carbon neutrality, and the integration of hydrogen energy technology has gradually expanded in recent years.

Overseas, countries such as the Netherlands and Germany have introduced hydrogen-based greenhouse systems. In the Netherlands, the government and private sector are cooperating to develop a self-sufficient energy system that utilizes hydrogen fuel cells to provide both heating and power for greenhouses. The closed loop system uses electricity from solar and wind power to electrolyze water and produce hydrogen, which is then reused through fuel cells. Compared to conventional fossil fuel-based systems, this strategy benefits from a significant reduction in GHG emissions.

While solar and wind power are popular renewable energy sources without active carbon emissions, they suffer from both intermittency and volatility, with generation varying with climate and time of day. This volatility can lead to difficulties in maintaining energy supply stability and grid balance. To mitigate this, renewable energy-coupled hydrogen energy storage systems have been proposed in which hydrogen is produced by electrolyzing water with renewable energy power and stored and converted to electricity through fuel cells when needed. Since hydrogen can be stored for long periods and on a large scale, it can effectively resolve the energy supply－demand imbalance regardless of the climate (Egeland-Eriksen et al., 2021).

Recently, energy systems utilizing hydrogen fuel cells have been developed for agricultural facilities such as smart farms and greenhouses, and research on performance, economics, and efficiency evaluation is actively underway. Solid oxide fuel cells are promising as energy supply systems due to their high electrical efficiency, and energy savings of up to 12% have been reported during heating periods (Ham et al., 2024). Hydrogen fuel cell systems have shown significantly reduced energy consumption and GHG emissions compared to conventional fossil fuel-based systems in agricultural practice. In addition, the cost of hydrogen production based on renewable energy such as solar and wind varies from $2.92/kg to $6.69/kg depending on local conditions and technological level, and has gradually decreased with technological advances (Sadeghi Chamazkoti et al., 2025). This successful integration of renewable energy and hydrogen production is an important demonstration of the potential for energy-independent agriculture, providing a useful foundation for achieving carbon neutrality.

In Germany, the Hydrogen Power Storage & Solutions East Germany (HYPOS) project aims to produce and utilize renewable energy-based green hydrogen. As a full-cycle demonstration network, HYPOS has established an operating model that converts and stores solar and wind power into hydrogen and combines pipeline-based local supply with large-scale storage (HYPOS e.V., 2023). The project has been promoting the utilization of hydrogen in various sectors, including agriculture and local communities. In agriculture, fuel cells have been applied in smart greenhouses and watering systems to provide power and efficient energy management based on real-time monitoring. This is a prime example of an infrastructure-first approach to mitigate renewable energy intermittency and support energy independence in agriculture. In North America, cloud-based management platforms have been integrated with hydrogen fuel cells to increase energy independence and sustainability in rural areas, simultaneously boosting productivity and efficiency. Based on its hydrogen economy roadmap, Japan has also demonstrated advances agricultural production and energy self-sufficiency related to hydrogen fuel cell applications in smart farms and cultivation facilities.

In the Republic of Korea, hydrogen-based energy systems have been actively adopted in the agricultural sector to achieve its 2050 carbon neutrality goal. In Gyeongsangbuk-do, a pilot project is underway to apply hydrogen production in conjunction with solar power generation to heat and power greenhouses on smart farms, with initial results showing energy cost savings and productivity improvements. In Jeollabuk-do, the Korea Institute of Energy Research reported that a smart farm energy model integrated with hydrogen infrastructure demonstrated simultaneous heat and power supply using a small 1.5 kW fuel cell for a smart greenhouse. Private companies have also been attempting to build self-sustaining agricultural facilities utilizing hydrogen fuel cells, but initial investment costs and economic feasibility remain challenging. In parallel, biogas-based hydrogen production technology utilizing agricultural by-products and wastes has been investigated, and resource circulation and energy efficiency improvement strategies are being explored.

In the Republic of Korea, hydrogen-based energy systems have been actively adopted in the agricultural sector to achieve its 2050 carbon neutrality goal. In Gyeongsangbuk-do, a pilot project is underway to apply hydrogen production in conjunction with solar power generation to smart farms to heat and power greenhouses, with initial results showing energy cost savings and productivity improvements. In Jeollabuk-do, the Korea Institute of Energy Research reported that a smart farm energy model integrated with hydrogen infrastructure demonstrated simultaneous heat and power supply using a small 1.5 kW fuel cell for a smart greenhouse. Private companies have also been attempting to build self-sustaining agricultural facilities using hydrogen fuel cells, but the initial investment cost and economic viability remain challenging. In parallel, biogas-based hydrogen production technology utilizing agricultural by-products and wastes has been investigated , and resource circulation and energy efficiency improvement strategies are being explored.

In addition to the smart farm sector, the agricultural machinery sector may have a significant role in reducing GHG emissions from agriculture using alternative hydrogen technology. Hydrogen can be utilized in off-grid areas or in agricultural machinery and transportation applications that require high-powered energy. Hydrogen fuel cells offer higher energy density and longer run times than electric batteries, contributing to the wider use of renewable energy (Varlese et al., 2025). According to Market Research Future (2024), the hydrogen fuel cell-based tractor market is expected to grow in North America and Europe from approximately $200 million and $150 million in 2023 to $1.8 billion and $1.5 billion by 2032, respectively. During the same period, the market in Asia is expected to expand from $100 million to $1 billion, Latin America from $50 million to $500 million, and the Middle East and Africa from $40 million to $200 million. These trends show that hydrogen fuel cell technology is likely to be rapidly adopted in the agricultural sector.

Hydrogen fuel cell tractors have the advantages of zero emissions, low noise, and high energy efficiency compared to conventional diesel-based tractors (Lombardi et al., 2023). In a recent study, hydrogen fuel cell-based agricultural machinery showed 47.9% energy efficiency in plowing operations, compared to the 29.3% of diesel engines (Jeon et al., 2024). Similarly, hydrogen-fueled hydraulic engine systems that convert hydrogen directly into hydraulic energy have shown conversion efficiencies of up to 43.8%, significantly exceeding the average efficiency of conventional internal combustion engines (about 30%) (Varlese et al., 2024).

The main technical challenge for hydrogen fuel cells in agricultural machinery is efficient energy management under different working conditions. In a distributed-drive hydrogen-electric tractor, fuel consumption could be reduced by 15.39-25.40% by optimally distributing the drive power according to the working conditions (Li et al., 2024). In addition, a predictive energy management strategy (Predictive EMS) has been proposed that predicts the average load of an agricultural field in advance and operates the fuel cell at a constant power level, which mitigates the degradation of fuel cell performance that occurs due to load fluctuations and high and low power operation (Varlese et al., 2024).

Economic analyses are also underway. A hydrogen fuel cell hybrid system (FCS), which can replace a diesel engine, showed about 81-88% higher efficiency than diesel engines. A total cost of ownership analysis revealed that hydrogen is economically feasible at a diesel price of 3.25 USD/gal, hydrogen price of between 5.79 and 6.85 USD/kg, and FCS system cost of approximately 323 USD/kW (Ahluwalia et al., 2022). However, liquid hydrogen storage systems and equipment packaging technologies require improvement to achieve and maintain operating conditions. In addition, a novel energy management strategy utilizing empirical mode decomposition (EMD) and variational mode decomposition (VMD) has been proposed to improve fuel cell responsiveness; the VMD strategy improved efficiency by up to 27.31% compared to EMD, reduced hydrogen consumption by 3.49%, and achieved a maximum output efficiency of 55.0% (Zhang et al., 2024).

Based on these technical and economic advances, various empirical studies are being conducted in the industry. In a review on the technological trends, Son et al. (2023) reported that New Holland Agriculture developed and launched an NH2 hydrogen fuel cell tractor. In addition, Fendt in Germany has built a hydrogen tractor prototype and is preparing to launch a product. In the Republic of Korea, a consortium of industry, academia, and researchers centered at Chungnam National University, Hyundai Mobis, and KAIST, with support from the Ministry of Agriculture, Food, and Rural Affairs, has been developing a 110 kW hydrogen fuel cell tractor. The prototype was unveiled in November 2024 at the Korea International Exhibition of Machinery, Equipment, Science and Technology for Agriculture (KIEMSTA). Daedong Corporation and LS Mtron are also involved in the project, and aim to develop a hydrogen fuel cell-based agricultural machinery platform by 2026. Hyundai Motor Company has also been conducting initial research but has avoided commercialization due to a lack of charging infrastructure and high initial investment costs. Expanding the hydrogen supply chain, reducing the cost of fuel cell systems, and improving technical issues are key challenges in the Republic of Korea.

Conclusions and Implications

This study reviewed the current status of carbon neutrality in the Republic of Korea, among other countries, and analyzed the application of hydrogen technology in the agricultural sector. As the international community strengthens efforts toward carbon neutrality in response to the climate crisis, it is essential for the agricultural sector to transition to sustainable technologies. In particular, the use of hydrogen energy in smart farms and agricultural machinery has gradually increased, and hydrogen technology has been key for realizing carbon neutral agricultural initiatives. In the smart farm sector, renewable energy-based green hydrogen systems have been demonstrated and operated at national and regional levels in other countries. In the Republic of Korea, demonstration projects are also pursued in Gyeongsangbuk-do and Jeollabuk-do, but there are limitations such as lack of hydrogen infrastructure and burdensome initial investment costs. In the field of agricultural machinery, major manufacturers in Europe and North America have been seeking commercialization through prototype development and empirical research, and the Republic of Korea has developed the world’s first 110 kW hydrogen fuel cell tractor through a collaboration among industry, academia, and research institutions. However, expanding infrastructure, securing affordability, and strengthening system durability are key challenges.

In terms of policy and technological implications, a phased approach is needed. In the short term, it is necessary to promote demonstration projects nationwide, government-led charging infrastructure, and technological standardization. In the medium term, joint research based on industry－academia－research collaboration should be strengthened to address technological issues associated with the characteristics of agricultural sites and secure economic feasibility. In the long term, it is essential to establish financial incentives and institutional support systems as well as education to increase farmer acceptance of the technology.

A limitation of this study is its focus on case studies and literature analysis. Thus, future research should incorporate LCA and LCC studies based on empirical data. Furthermore, a comparison of international cooperative cases and the validation of the rural hydrogen hub model would greatly contribute to the diffusion of hydrogen technology in agriculture.