At its simplest, green hydrogen is hydrogen produced with zero net carbon emissions.
While hydrogen is the most abundant element in the universe, it does not exist on its own on Earth; it has to be separated from other molecules. The “colour” of hydrogen tells you exactly how it was extracted. While traditional “grey” hydrogen relies on fossil fuels, green hydrogen is created using entirely renewable energy.
How Green Hydrogen is Made
The process relies on water electrolysis. An electric current runs through water inside an electrolysis unit, splitting the water ($H_2O$) into its base components: hydrogen ($H_2$) and oxygen ($O_2$).
For the hydrogen to be truly “green”, the electricity powering that electrolysis unit must come from renewable sources like offshore wind farms or solar arrays. When burned or used in a fuel cell, the only by-product is water vapour, creating a completely closed-loop, zero-emission fuel lifecycle.
Why It Matters for the UK’s Net Zero Goals
The UK has a legally binding target to achieve net zero greenhouse gas emissions by 2050. While renewable electricity can easily power cars and homes, there are major sectors of the economy that batteries simply cannot handle. This is where green hydrogen becomes a necessity.
1. Decarbonising “Hard-to-Abate” Sectors
Heavy industry—such as steel manufacturing, chemical plants, and glassmaking—requires intense high-temperature heat that electric batteries cannot efficiently deliver. Green hydrogen can burn hot enough to replace natural gas in these furnaces. Similarly, heavy transport like shipping, aviation, and HGVs (heavy goods vehicles) benefit from hydrogen’s high energy density and quick refuelling times compared to massive battery packs.
2. Balancing the National Grid (Energy Storage)
Wind and solar power are intermittent; the wind does not always blow when energy demand peaks. When the UK’s massive offshore wind farms produce excess electricity on stormy nights, that surplus power can be directed into electrolysis units. The resulting green hydrogen acts as a “chemical battery”, storing that energy in safety tanks for weeks or months until it is needed to generate electricity back onto the grid.
3. Achieving Energy Independence
By utilising homegrown offshore wind from the North Sea to generate hydrogen, the UK can significantly insulate itself from volatile global fossil fuel markets, securing a domestic, reliable supply of industrial fuel and clean power.
The Government Strategy: The UK government’s Hydrogen Strategy targets up to 10GW of low-carbon hydrogen production capacity, aiming for at least half of this to come from green hydrogen, driving billions in green investment and creating thousands of jobs across regional industrial clusters.