With green hydrogen, we're in our element

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Hydrogen is a hot topic. Some tout it as a miracle solution - others dismiss it as ‘techno-topian’ nonsense. So what’s really going on?

Octopus Hydrogen believes that the right kind of hydrogen is lovely ‘green hydrogen’. This precious gas could play a huge role in decarbonising some tricky, long-neglected areas like aviation, heavy transport and industry.

Still, when talking about this cutting-edge tech you’ve got to be careful. Hydrogen comes in many colours - not just ‘green’, but also ‘blue’ and ‘grey’, which can be considered less clean. And what’s more, when it comes to decarbonising other areas - like home heating - the UK has more viable alternatives like heat pumps.

Between Octopus Energy Generation and Octopus Hydrogen, Octopus Energy has assembled an elite, relentlessly-focused team of hydrogen experts, who are spending a whopping £3bn to put the right kind of hydrogen towards the right kind of solutions…

So what is this mysterious thing we call hydrogen?

Hydrogen is the most common chemical element out there. It makes up three quarters of the matter in our universe; the vast majority of the Sun is made of hydrogen (which it uses for fuel) - so are the giant planets Jupiter and Saturn.

A graphic showing a hydrogen atom

Here on Earth there’s tonnes of the stuff too - but it can be pretty difficult to find in its raw form. Hydrogen is usually locked away, bound up together with other common substances: for example, hydrogen is the ‘H’ in H2O (water), and the ‘hydro’ in ‘hydrocarbons’ (such as coal, oil, and gas). All you have to do is break substances like these down, separating them into their chemical constituents - and voila! You’ve got a ready supply of hydrogen.

Once separated, this hydrogen gas can then be used in a 'hydrogen fuel cell', which in practice, works a bit like a battery. Inside the fuel cell, hydrogen and oxygen 'recombine' to create an electrical current - generating power.

As a flammable gas, hydrogen can be also burnt to generate heat (energy) on demand. This is more useful when it comes to decarbonising industrial processes than transport. What’s exciting here is that hydrogen burns clean. Burning it (at least) doesn’t give off any greenhouse gas emissions - the only by-products are water and water vapour!

Here then, we have the potential for a low-carbon energy source - just as long as we can find a low-carbon way to produce it…

What different types of hydrogen are there?

We can produce hydrogen in a number of ways, and some of these methods are much greener than others, so it’s helpful to know the difference…

Grey hydrogen


‘Grey’ hydrogen is usually made by separating natural gas (methane) a ‘hydrocarbon-based’ fossil fuel, into hydrogen (useful) and both carbon monoxide and carbon dioxide (dirty). Sadly, the large amounts of carbon given off in this process make grey hydrogen extremely carbon intensive - and this is how 98% of the World’s hydrogen is made today.

Blue hydrogen


‘Blue’ hydrogen is usually made in the same way as grey hydrogen, but *in theory* the resulting carbon emissions are captured and stored - often by pumping them underground.

In practice, this is proving difficult. Carbon capture technologies come with big risks, and often fail on their proposed C02 capture and storage targets - by as much as 80%. In the future we might see more success, but for the time being this puts blue hydrogen firmly in the ‘not worth it’ category. Others have also been quick to point out that getting hydrogen from hydrocarbons like natural gas will keep us dependent on fossil fuels for the foreseeable future.

Green hydrogen


‘Green’ hydrogen is the gold standard in hydrogen generation. Here, hydrogen is produced via an electric current, which separates water (H2O) into hydrogen and oxygen in a process called ‘electrolysis’. For one, electrolysis is tried and tested - we’ve been doing it for hundreds of years to separate metallic ores and cover objects with metal coatings, for example. What’s more, so long as the electricity used to power the process comes from renewable sources, hydrogen production can be carbon neutral!

Still, it’s worth noting that making green hydrogen is fairly energy intensive for the time being, and so this method currently makes up a relatively small portion of hydrogen production overall.

That’s what Octopus Hydrogen is here to change.

Green Hydrogen or go home

Given that ‘grey hydrogen’ is heavily polluting - dirtier, even than coal, and ‘blue hydrogen’ is proving difficult to roll out in practice, green hydrogen clearly looks the most promising. Beyond the fact that it burns without carbon emissions, what’s so exciting about green hydrogen is that it can also be produced with renewable energy when we've got more than we can use.

a graphic showing solar and wind farms

To give a little more backstory: tomorrow’s electricity will be powered by massive amounts of clean, green, solar and wind energy. This is already good news for green hydrogen - more renewable generation will make electricity cheaper, making green hydrogen cheaper to produce too.

But that’s not all, given that we can’t control exactly when the sun shines or the wind blows, there will be times when there’s tonnes of excess green energy in the electrical grid (in fact, on some especially windy days this happens already!) To avoid an ‘imbalance’ on the grid (which can be dangerous) extra renewable supply is often turned off. This is a terrible waste, especially when we still rely on fossil fuels at other times.

Instead of turning off the turbines, we should be using some of this extra green energy to generate green hydrogen. That hydrogen could then be used, instead of gas and oil, to tackle a whole load of carbon-intensive industries. Over the next few years, as renewable energy continues to get cheaper (and green hydrogen with it), we could see this hydrogen being used for more and more.

Octopus are investing £3 billion in green hydrogen production

an image of an Octopus Turbine

Octopus is committed to making green hydrogen a reality. Octopus Energy Generation - the arm of the Octopus Energy group who build and operate hundreds of wind and solar farms across Europe - have, together with independent renewable giant RES, pledged to invest a massive £3bn into growing green hydrogen production over the next ten years.

Octopus Hydrogen: driving decarbonisation with green hydrogen

Still, if green hydrogen is going to decarbonise tricky, hard to reach sectors, we’re going to need to develop and scale up hydrogen-based technologies and applications, as well as green hydrogen generation itself.

To this end, in 2021 Octopus founded Octopus Hydrogen. This crack-squad of hydrogen experts are working with a number of cutting-edge green hydrogen projects, supplying the fuel and expertise needed to make green hydrogen work as hard as possible.

Given that producing green hydrogen is still fairly energy intensive, Octopus Hydrogen work hard to decide where to concentrate their efforts. In some areas, it’s worth remembering that green hydrogen still has quite a way to go; in others there are clearly better alternatives. Still, in sectors like transport, hydrogen can already compete with existing, dirtier fuels - and here Octopus Hydrogen has got the ball well and truly rolling... So what do Octopus Hydrogen plan to use Hydrogen for?

Hydrogen-powered heavy transport

The transport sector now makes up a massive 27% of the UK’s carbon emissions. Some modes of transportation, cars being an obvious example, are already undergoing a green electrical revolution - just think about the current EVs boom. But ‘heavy’ transportation - lorries, aviation, shipping, and certain rail routes - are proving much trickier to clean up. Often, the issue is that batteries just don’t quite pack the punch needed to get a lorry trundling, or a plane off the ground.

Hydrogen, however, can do the job well, and so long as it’s generated in a green way, it’s looking like one of the most promising ways to decarbonise these industries. When it comes to transport green hydrogen is already able to compete with existing fuel sources. At the moment, this is where Octopus Hydrogen’s efforts are largely focussed…

Hydrogen lorries

In April, Octopus Hydrogen’s groundbreaking partnership with MIRA Technology Park in the Midlands is set to go live!

Octopus Hydrogen are setting up refueling centres for hydrogen powered lorries across the UK - and this site in the Midlands will be the first of many.

Here you can really see the hydrogen industry picking up pace. It’s taken ages to develop the first hydrogen refuelling stations, but innovation, agility, and snowballing interest mean Octopus Hydrogen have been able to do it in a year!

Hydrogen Powered Planes

Flight contributes a significant portion of global greenhouse gas emissions, and so far, has barely been touched by existing decarbonisation efforts. Hydrogen could be the future of low-carbon travel.

An image of a ZeroAvia plane

Image Credit: ZeroAvia

Octopus Hydrogen is providing 100% green hydrogen to help develop some of the world's first commercial hydrogen-electric planes. They've partnered with green aviators ZeroAvia to power a commercial aircraft with 500 nautical mile range, driven by a 600kW hydrogen-electric fuel cell. ZeroAvia plans to bring their technology to market by 2024, helping commercial zero-emission flights become a reality.

Clean hydrogen power when the wind isn’t blowing

We’ve mentioned that renewable energy generation is ‘intermittent’, we can’t control when the sun shines and the wind blows. This means that at some points we have a huge excess of green electrons, while at others they are relatively scarce.

A graphic showing green energy running into a hydrogen plant

Green hydrogen can help here because it offers a way to ‘store up’ and then ‘call on’ green energy whenever we need it. First, we use renewables to generate green hydrogen via electrolysis when solar and wind energy are abundant, then later, we can burn that hydrogen to generate energy when we need it. Just like we previously did with gas, only without the harmful emissions.

Still, hydrogen is quite energy intensive (and expensive) to make. This means that at the moment, there are only certain times (when energy is in really high demand) when it would be worth burning green hydrogen to generate energy. Often, that green hydrogen would often be better used elsewhere (like transport, as we mentioned earlier).

It’s also worth bearing in mind that the UK’s electricity is always getting greener, but at the moment it’s still only about 40% renewable. We must make sure that we produce hydrogen when the grid is exceptionally green, otherwise generating it to help balance the grid could end up producing more carbon than it would save.

Nevertheless as renewables expand, the grid will get greener and energy will get cheaper, and Octopus Hydrogen's experts are confident that balancing the grid with green hydrogen is only going to become more and more viable - watch this space!

Is it better to encourage customers to use up abundant electricity, or generate hydrogen with it? Technical Level 🌶️


At the moment, the average level of energy demand in the UK is around 30GW, with peak demand reaching 60GW. The UK currently has the capacity to 10GW of energy from offshore wind farms alone. By 2035 we’re aiming for a whopping 40GW. With renewable capacity like that, we’re gonna need to call on everything we can to soak all that extra green energy and make sure it doesn’t go to waste. That means customers will need to be enticed with super cheap energy (as Octopus is already encouraging with their smart tariffs and trials), EVs and batteries are gonna need to turn on and store up what they can, and green hydrogen generation plants are going to have to use up as much as possible too. In short, it’s not an either or - there will be more than enough green electrons to go around!

Heavy industry

In the future, Octopus Hydrogen will also look to provide green hydrogen for heavy industry. Lots of industrial processes, such as the production of concrete, steel, and cement require high temperatures, which are currently generated by burning tonnes of carbon-intensive fossil fuels like gas, coal, and coke. Thankfully, green hydrogen also burns hot, but without any of the emissions.

It’s worth remembering that many industrial processes can be electrified without hydrogen. A recent paper suggested that of 11 industries in Europe - accounting for 92% of heavy industry CO2 emissions - 78% of the energy demand could be electrified with established technologies. For example, electric arc furnaces already account for more than 40% of european steel production, melting down scrap.

Still, even in this scenario, that leaves over a fifth of industrial practices open to decarbonisation via green hydrogen, so there’s little doubt that it’s worth exploring, especially as green hydrogen becomes cheaper.

What shouldn’t we use hydrogen for?

‘We have to be smart with hydrogen. Green hydrogen is great, but there are some areas where alternative low-carbon technologies look much more appropriate.’ Octopus Hydrogen CEO Will Rowe tells me.

Home heating, which currently makes up 14% of the UK’s carbon footprint, is a great example of an area where hydrogen isn’t the best solution.

As fossil fuels continue to lose the fight for energy supremacy, many large fossils giants are making noise about ‘sustainability’ and ‘green energy’, especially where heating is concerned. Some are touting solutions like hydrogen boilers, proposing that they repurpose the existing gas network to carry hydrogen rather than natural gas. Others are suggesting we try and make our gas network a smidge greener by blending 20% hydrogen into the existing gas grid…

In the UK, ‘re-purposing’ the polluting gas network for hydrogen would be a huge job. We’d have to switch out millions of boilers simultaneously, as well as 'relaxing' 15% of the pipes in the network. Estimates are currently somewhere around an eye-watering £1bn, and this still doesn't include the 'hidden' costs of replacing appliances like hobs and fires.

What’s more, you really have to wonder whether those behind these efforts are really driven by a true desire to transform the world’s energy, or if these fossil fuel companies are more concerned about their long-invested gas pipes and other infrastructure that might become redundant in an all-electric world.

A graphic showing a heat pump next to a house

Having weighed the evidence, in the race for green heating, Octopus is backing heat pumps rather than hydrogen boilers. For starters, they’re already here - they’re a tried and tested technology - while hydrogen boilers are still quite some way off. Heat pumps are also up to 4X more efficient, safer, and likely to be far cheaper too.

On a personal level, according to the International Council on Clean Transportation “By 2050, it’s thought that heat pumps will be more cost-effective than hydrogen-only [heating] technologies”. To be precise, they estimate that in Europe, a heat pump will cost an average £496 a year, including energy bills, compared to £1,090 for a hydrogen boiler.

So what’s next for hydrogen at Octopus?

In the next few years, we’re going to see Octopus invest heavily in green hydrogen production. Together with RES, the UK’s largest independent renewable generator, Octopus Energy Generation will use their collective expertise, and resources, to develop, and operate £3 billion worth of hydrogen plants powered by clean, green, renewable energy.

At the same time, Octopus Hydrogen will be going above and beyond to power all sorts of cutting-edge applications. Who knows, maybe one day you’ll find yourself travelling guilt-free on a hydrogen-powered train, or plane, and realise that this is where it all kicked off.

Published on 8th March 2022 by:

image of Jackson Howarth

Jackson Howarth

Senior Writer

Hey I'm Constantine, welcome to Octopus Energy!