Hydrogen: The Invisible Giant Fueling the Clean Energy Revolution

Posted Date : 23 December 2025

Posted by : Preeti Wani

Hydrogen, the universe's most abundant element, is gradually stepping into the limelight. Despite its simplicity, comprising just one proton and one electron, hydrogen holds tremendous potential to transform the global energy landscape. Despite accelerating climate change, nations are shifting toward this invisible gas as a foundation of the transition toward a low-carbon, sustainable future.

From fueling zero-emission vehicles to decarbonizing heavy industry, hydrogen provides unmatched flexibility and scalability. But while it may seem to be a futuristic solution, the hydrogen economy is no longer a distant vision. With well-planned investments, technological breakthroughs, and international cooperation, hydrogen is on the verge of becoming a central pillar of the clean energy revolution.

What is Hydrogen and Why is it Significant?

Hydrogen is the lightest component and makes up about 75% of the universe's elemental mass. On Earth, it rarely exists in its original form and is mostly bound to other elements such as oxygen or carbon. To be used as an energy carrier, hydrogen is retrieved through various processes. Hydrogen is unique as it is clean at the point of use, producing only water vapor when used in fuel cells. Secondly, it has a high energy content per unit mass, nearly three times more than gasoline. It can be produced from a variety of resources, including water, natural gas, biomass, and renewables. Its versatility makes it a promising solution for sectors that are hard to electrify, such as long-haul transport, steelmaking, and chemical production.

Understanding Hydrogen's Color Codes

The environmental impact of hydrogen depends heavily on how it is produced. The industry segregates hydrogen based on color to represent its source and its related emissions.

Grey Hydrogen: Grey hydrogen is the most common type in use today. It is produced from natural gas via steam methane reforming (SMR), where natural gas reacts with steam at extreme temperatures. The process releases hydrogen, but it also produces a large amount of carbon dioxide into the atmosphere. Because the CO₂ isn't trapped or reused, grey hydrogen contributes significantly to greenhouse gas emissions. It is mainly used in oil refineries and fertilizer industries, but it's not aligned with global climate goals.

Blue Hydrogen: To reduce emissions, blue hydrogen builds on the same SMR process but adds carbon capture and storage (CCS). This means that instead of releasing CO₂ into the air, much of it is captured and either stored underground or put to use in other processes. Blue hydrogen is seen as a better option than grey hydrogen, offering a bridge between today’s modern technologies and the future of clean energy. Still, it depends on fossil fuels and on CCS systems, which aren’t always highly effective.

Green Hydrogen: Green hydrogen is regarded as the cleanest and most sustainable option. It is created by splitting water into hydrogen and oxygen using electricity, a process known as electrolysis. When that electricity comes from renewable sources like wind, solar, or hydropower, the hydrogen is produced without any emissions. Green hydrogen has the potential to clean up sectors that are difficult to electrify, such as steelmaking, aviation, and freight transport. Although it's currently more expensive due to the high cost of renewable electricity and equipment, prices are expected to come down as the technology matures.

Pink Hydrogen: Another rising option is pink hydrogen, made using the same electrolysis process as green hydrogen, but powered by nuclear energy instead of renewables. Because nuclear power doesn't produce carbon emissions during operation, pink hydrogen is also a low-carbon choice. It's especially relevant for countries with a strong nuclear energy base, like France and South Korea. One of its biggest strengths is the steady supply of energy, which isn’t affected by weather conditions.

Turquoise Hydrogen: Turquoise hydrogen is a newer and less-known method. It is made by heating methane in a process called methane pyrolysis, which breaks it down into hydrogen and solid carbon. Unlike grey or blue hydrogen, this method doesn't release carbon dioxide, just solid carbon, which can be stored or used in products such as tires or batteries. Although it's still in the testing phase, turquoise hydrogen could become a reliable, low-emission option if the technology becomes cost-effective and scalable.

Altogether, these color codes provide a helpful way to understand the environmental impact of different hydrogen sources. For policymakers, investors, and industries working to cut carbon emissions, knowing the difference is crucial. While green hydrogen represents the clean energy ideal, blue and turquoise hydrogen may help pave the way as we build up the technology and infrastructure needed for a zero-carbon future. As costs fall and innovation continues, hydrogen is expected to play a bigger role in the world’s clean energy mix.

Applications of Hydrogen: Fueling the Next Generation

• Transportation: Hydrogen fuel cells power electric vehicles (FCEVs) that emit only water. They are suitable for long-route trucks, buses, trains, and ships due to their fast-refueling times and long range.
• Industrial application: Hydrogen can serve as a substitute for fossil fuels in high-temperature industrial processes like steel and cement production. Additionally, it is used in applications such as purification and ammonia synthesis.
• Energy storage: Hydrogen can collect excess electricity generated by renewables. It helps to balance energy production with consumption and assures a stable grid functioning.
• Residential and commercial heating: Integrating hydrogen with natural gas or pure hydrogen in boilers can lead to lower carbon emissions.
• Aviation and maritime: Airbus and other aviation leaders are investing in hydrogen-powered aircraft. Similarly, hydrogen fuel cells in waterways can act as a substitute for diesel in marine transport.

Global Hydrogen Initiatives

The Challenges Ahead

Beyond its transformative promise, hydrogen faces many challenges before it can be adopted across different industries and landscapes. These challenges include economic, technological, infrastructural, and societal fields:

• High Production Expenses: In recent times, the cost of green hydrogen, generated through renewable-powered electrolysis, is comparatively more expensive than grey (fossil-based) and blue (carbon-captured) hydrogen. As of 2024, the cost of green hydrogen ranges between $4 and $6 per kilogram, whereas grey hydrogen can be produced for as little as $1 to $2 per kilogram. This cost disparity hampers its competitiveness in the market, especially in price-sensitive industries. Governments are offering subsidies, tax credits, and production incentives. Technological innovations, economies of scale, and falling renewable energy costs are expected to reduce green hydrogen prices by up to 60% by 2030, according to the IEA.
• Infrastructure Gaps: Hydrogen needs a dedicated infrastructure, i.e., pipelines, high-pressure storage systems, refueling stations, and safe transport mechanisms. At present, much of this infrastructure either doesn't exist or is dispersed and costly to build. Public-private partnerships are accelerating infrastructure build-outs. The EU's Hydrogen Backbone initiative, for example, aims to create a 40,000 km hydrogen pipeline by 2040.
• Energy Efficiency Concerns: Hydrogen's round-trip efficiency, from electricity to hydrogen and back to electricity, is low compared to direct battery storage. Electrolysis, compression, transport, and fuel cell conversion can result in energy losses of up to 60%. In many applications, especially in power storage or short-distance transport, batteries are more efficient. This makes hydrogen more suitable for long-term, high-capacity energy storage and industries that can’t be electrified easily. R&D efforts are guided to improve electrolyzers efficiency and create new materials and system designs to lower energy loss.
• Safety and Handling of Hydrogen: Hydrogen is highly flammable and is prone to easily leak due to its smaller molecular size. It burns with a nearly invisible flame, creating detection challenges, and requires specialized sensors and ventilation. International safety standards (e.g., ISO 14687) are being developed. Safety training, leak detection technologies, and strong storage protocols are being deployed in pilot projects.
• Public Awareness and Perception: Despite its advantages, hydrogen remains misunderstood by the general public and by few policymakers. Misconceptions about safety, feasibility, and environmental impact persist. Public support is important for project approvals, policy development, and consumer adoption, particularly in transport and heating.

While the road ahead is challenging, the emergence is undeniable. With continuous heavy investment and innovation, hydrogen can overcome these hurdles and fulfill its role as a foundation of the clean energy future.