Natural Gas: Bridge or Barrier in the Global Energy Transition?

In the global context of the energy transition, natural gas frequently emerges as a relevant component on the path toward a cleaner energy system. Although its role is subject to debate, mainly because it is a fossil fuel that emits methane, its flexibility, lower carbon intensity compared to coal, and established infrastructure make it a strategic vector to advance toward a future dominated by renewable energy sources.

Natural gas, composed primarily of methane (CH₄), produces less carbon dioxide per unit of energy than other fossil fuels. Compared to coal, its combustion generates significantly lower levels of pollutants, such as sulfur oxides, fine particulates, and nitrogen oxides. This lower pollutant load makes it a viable transitional option for sectors that cannot yet be fully electrified, such as heavy industry or long-distance transportation. Its adaptability makes it attractive not only for electricity generation but also for industrial applications, district heating, distributed cogeneration, and mobility, especially in its liquefied and compressed forms.

Moreover, the existing natural gas infrastructure represents a major advantage. Pipelines, distribution networks, compression and storage stations are assets that can be leveraged for emerging technologies, such as the injection of green hydrogen or biomethane. In this sense, natural gas can serve as both an immediate solution and a technological transition platform.

Natural gas remains a central component of national energy strategies. Many countries still consider it fundamental in their roadmaps toward 2030 and 2050. In various scenarios from the International Energy Agency (IEA), gas continues to play a significant role in supporting the phasing out of coal while the share of renewables increases. Its operational flexibility makes it an effective tool for balancing complex electrical grids. Combined cycle gas plants can start up or shut down quickly in response to solar or wind variability and can operate as backup when these clean sources do not generate enough to meet demand.

Another advantage of natural gas is that, in regions where full electrification is currently unfeasible, it offers an immediate improvement over more polluting technologies. Its use in rural, industrial, or low-density urban areas allows the energy transition to move forward without waiting for more advanced solutions to become available or financially viable. Furthermore, its use as a feedstock for producing gray hydrogen — with the potential to convert to blue hydrogen via carbon capture — lays the groundwork for a hydrogen economy that can later evolve into fully renewable production.

Natural gas has also proven to be a viable option for public and freight transportation, particularly in countries seeking a cleaner alternative to diesel while electric or hydrogen technologies are still developing. Buses, trucks, and municipal fleets operating on compressed natural gas (CNG) have achieved significant reductions in local emissions, improving urban air quality.

However, one of the main criticisms of natural gas is that it remains a fossil fuel and therefore emits CO₂ when burned. Moreover, throughout its value chain, from extraction to distribution, methane leaks can occur. Methane is a greenhouse gas with a global warming potential up to 84 times greater than carbon dioxide over a 20-year period. These fugitive emissions can offset the environmental benefits usually attributed to gas compared to other hydrocarbons. For this reason, it is essential to establish robust monitoring, detection, and leak-repair systems to ensure that the use of natural gas aligns with climate goals.

There is also a risk that large investments in gas infrastructure could become stranded assets if the transition to clean energy sources accelerates. In such a case, gas plants, pipelines, or terminals could lose value or become obsolete if market or regulatory conditions turn against fossil fuels. Avoiding this outcome requires a strategic vision that ensures these investments are adaptable or complementary to future technologies, such as hydrogen or biomethane.

In certain applications, particularly urban ones, more efficient and cleaner alternatives to natural gas already exist. For instance, electric heating systems using heat pumps, or the direct electrification of public transport, can offer lower emissions and operational costs in the long term. Relying on gas in such contexts could delay the adoption of more sustainable solutions unless a clear timeline for its gradual phase-out is established.

In terms of production, some countries face limitations that hinder energy autonomy based on natural gas. Mexico, for example, has experienced a sustained decline in domestic dry gas production in recent years. Although demand has increased, domestic supply has been insufficient, leading to a growing dependence on imports from the United States. This raises concerns about energy security and vulnerability to external price or supply shocks.

Despite these limitations, there are clear signs that natural gas continues to play an active role in the energy transition. Globally, it remains the third most used source of primary energy, behind oil and coal. In countries such as Spain, natural gas has been recognized as a key component in replacing coal for electricity generation, especially during peak demand periods. Additionally, technologies such as biomethane, a renewable gas produced from organic waste, are beginning to gain ground as a green substitute for conventional gas, compatible with existing networks and with significantly lower climate impacts.

The rise of biomethane is reshaping the energy landscape. In Europe, numerous utility companies have started injecting biomethane into conventional gas grids, allowing part of domestic and industrial consumption to have a much lower carbon footprint. In Spain, for instance, the energy company Naturgy increased its biomethane injection capacity by more than 30% in a single year, thanks to the operation of new plants based on agro-industrial and urban waste.

On the international stage, the production and export of liquefied natural gas (LNG) have also gained momentum. The United States has become one of the world’s largest suppliers, with over 60% growth in export capacity in the last five years. This has positioned the country as a central player in the global gas market, while also creating new supply routes for European nations seeking to reduce their dependence on Russian gas.

To ensure that natural gas effectively serves as a transition vector, it must be integrated into a comprehensive and coordinated strategy. This means acting on multiple fronts: strengthening methane emission monitoring and control systems, promoting the development of biomethane and green hydrogen, updating regulatory frameworks, designing pricing mechanisms that reflect environmental costs, and planning the progressive phase-out of gas plants once clean alternatives become fully competitive.

In summary, natural gas is not the destination, but it can serve as a necessary and useful bridge toward a more diverse energy matrix in line with the energy transition. If used intelligently and under strict environmental criteria, it can help accelerate the transition without compromising energy security or creating unintended socioeconomic consequences. The challenge lies in ensuring it does not become an excuse for climate inaction, but rather a temporary resource to help build a truly clean energy system.