Hydrogen

A key part of a clean and secure energy future

Hydrogen can help tackle various critical energy challenges, including helping to store the variable output from renewables like solar and wind to better match demand. It offers ways to decarbonise a range of sectors – including long-haul transport, chemicals, and iron and steel – where it is proving difficult to meaningfully reduce emissions. It can also help improve air quality and strengthen energy security.


Why hydrogen?

Hydrogen is not an energy source but an energy carrier, which means that its potential role has similarities with that of electricity. Both hydrogen and electricity can be produced by various energy sources and technologies. Both are versatile and can be used in many different applications.

No greenhouse gases, particulates, sulphur oxides or ground level ozone are produced from the use of either hydrogen or electricity. If the hydrogen is used in a fuel cell, it emits nothing but water. However, both hydrogen and electricity can have a high CO2 intensity upstream if produced from fossil fuels such as coal, oil or natural gas.

The crucial difference between hydrogen and electricity is that hydrogen is a chemical energy carrier, which means it can be stored and transported in a stable way, as is done today with oil, coal, biomass and natural gas.  Hydrogen can also be combined with other elements such as carbon and nitrogen to make hydrogen-based fuels that are easier to handle, and can be used as feedstock in industry, helping to reduce emissions.

Without hydrogen a decarbonised energy system based on electricity would be much more flow-based. Flow-based energy systems must match demand and supply in real time, across wide distances, and can be vulnerable to disruptions of supply. Chemical energy can add a stock-based element to an energy economy and thus contribute significantly to energy system resilience.

What do we use it for?

Producing hydrogen for industrial uses is a major business globally. Demand for hydrogen, which has grown more than threefold since 1975, continues to rise. Today, hydrogen is used mostly in oil refining and for the production of fertilisers.

	Refining	Ammonia	Other
1975	6.2	10.877	1.077
1980	6.831	16.171	1.456
1985	8.563	20	1.847
1990	12.033	21.411	1.9
1995	15.829	21.96	2.042
2000	21.449	28.565	2.484
2005	25.257	26.141	2.691
2010	30.974	28.345	3.105
2015	35.965	31.921	3.813
2018e	38.243	31.458	4.188
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Demand for pure hydrogen is almost entirely supplied from fossil fuels, with 6% of global natural gas and 2% of global coal going to hydrogen production.  As a consequence, production of hydrogen is responsible for CO2 emissions of around 830 million tonnes of carbon dioxide per year, equivalent to the CO2 emissions of Indonesia and the United Kingdom combined. In energy terms, total annual hydrogen demand worldwide is around 330 million tonnes of oil equivalent (Mtoe), larger than the primary energy supply of Germany.

Today's hydrogen value chains

The existing markets for hydrogen build on its attributes: it is light, storable, reactive, has high energy content per unit mass, and can be readily produced at industrial scale. Today’s growing interest in the widespread use of hydrogen for clean energy systems rests largely on two additional attributes: 1) hydrogen can be used without direct emissions of air pollutants or greenhouse gases; and 2) it can be made from a diverse range of low-carbon energy sources.

Broadly speaking, hydrogen can contribute to a resilient, sustainable energy future in two ways:

  1. Existing applications of hydrogen can use hydrogen produced using alternative, cleaner production methods, and from a more diverse set of energy sources.
  2. Hydrogen can be used in a wide range of new applications as an alternative to current fuels and inputs, or as a complement to the greater use of electricity in these applications. In these cases – for example in transport, heating, steel production and electricity – hydrogen can be used in its pure form, or converted to hydrogen-based fuels, including synthetic methane, synthetic liquid fuels, ammonia and methanol.

In both ways, hydrogen has the potential to reinforce and connect different parts of the energy system. By producing hydrogen, renewable electricity can be used in applications that are better served by chemical fuels. Low-carbon energy can be supplied over very long distances, and electricity can be stored to meet weekly or monthly imbalances in supply and demand.

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