Author: Bernadette Ballantyne
Supporter: Mott Macdonald
Hydrogen is the most abundant and energy dense element in the Universe. It is the conversion of hydrogen to helium through nuclear fusion in the core of the sun that generates its incredible power. Burning it creates clean electricity and heat without generating carbon emissions, but to utilise it, first it must be released from the organic materials or water that host it. So how do we capture its potential to create clean energy systems of the future in a safe and cost-effective way? A step that the government’s Committee on Climate Change says is vital if the UK is to meet its ambitions of being a net zero carbon country by 2050.
“In our report there is a call to arms for two things. One is a very deep electrification of the economy. The second is a move to hydrogen and without both we are very unlikely to get to net zero in the UK,” says Chris Stark, chief executive of the Committee on Climate Change. Getting to net zero is the focus of a new report that reassesses the UK’s long-term emission targets. Produced at the request of the government, it says that to meet the UK’s obligations in the Paris Agreement, which aims to keep global carbon emissions down to under two degrees, the UK should set a new target. It should aim to become a net zero emitter of greenhouse gases by 2050, which means a 100 percent reduction on 1990 emission levels. The current target is an 80 percent reduction.
But if it were easy to convert hydrogen to electricity or heat surely, we would all be using it by now? “The difficulty that we have with hydrogen is that it has to be synthesised or extracted from its compounds. It is a very flexible gas it serves as an energy transport and potential storage, but it comes with challenges,” says Ian Clarke, global sector leader for energy at consultant Mott MacDonald. “There are a few technical challenges with how we might store and transport it. It is very clean, particularly in combustion, it has very environmentally friendly by products, typically water vapour which is clearly an advantage.”
Timing Critical for Hydrogen
Ian says that it is these benefits of clean combustion, flexibility, and its ultimate ability to connect energy sources with a multitude of end users, which mean that although a hydrogen energy system has not yet taken off, the idea never goes away. In fact as global efforts to combat climate change accelerate, and decarbonisation becomes increasingly urgent, hydrogen is back on the agenda.
In fact Chris says that the period between now and 2050 is crucial with a potential doubling of the global economy and massive investment in global infrastructure, making it even more vital that we find new ways to meet energy demand through greater electrification and harnessing the benefits of hydrogen. “If we lock in fossil fuels and that paradigm of growth over that period then we are stuffed,” says Chris.
Instead of locking in fossil fuels the report calls on government to set policies that support the deployment of renewables and decarbonisation of back up generation including using hydrogen as a low carbon fuel for industry, transport and powering homes.
“Hydrogen is the answer to how we get to the full zero emissions that we will need probably by the mid 2030s and 2040s in electricity production as we convert and fuel switch CCGTs and OCGTs to zero emissions using hydrogen,” explains Chris. “We must now have a proper strategy for carbon capture and storage and the link there is with hydrogen supply and we still see that the majority of the hydrogen that the UK will use will come from natural gas and SMR.”
SMR stands for steam methane reformation and In exploring hydrogen’s potential in the energy system there are a lot of terms that we need to understand, like SMR, and to do that we need someone who knows all about hydrogen. “Steam methane reforming is the basic and the oldest type of hydrogen production technology available,” says Chris De Beer, energy storage specialist at Mott MacDonald. “It is heavily used in industry. So the basic concept is that you take methane or a hydrocarbon, you run it through a steam methane reforming cycle, which consists of a catalyst bed, where you basically crack the hydrocarbon into hydrogen and carbon dioxide. These days they use a carbon capture back end on the system to really reduce the emissions.”
Splitting out the Hydrogen
And this is crucial because although combustion of hydrogen to make electricity is carbon free, production of hydrogen through steam methane reformation is not, and furthermore it requires natural gas to make it. Looking ahead there are other technologies that can be used to create fossil fuel and carbon free hydrogen such as electrolysis. “Electrolysis is the mechanism that we refer to for splitting water into its constituent elements, which is really hydrogen and oxygen,” says Chris De Beer.
Two molecules of hydrogen and one molecule of oxygen or H2O is better known as water, the most abundant resource we have on the planet. “You take electricity and you run it through a cell, it can either be a polymer electrolyte membrane cell or an alkaline cell – there are various technologies – and what it effectively does is it enforces the electrochemical reaction whereby you take the electricity that comes in and the water that comes in as a reactant and you split it into hydrogen and oxygen,” says Chris De Beer.
Making hydrogen via electrolysis is something that experts are able to do, but although it has the advantage of being fossil fuel free, it requires electricity to make it work and it is more expensive than the SMR method. Arnaud de Lhoneux, is the business manager for renewable hydrogen at hydrogen production company Hydrogenics, which has made over 500 electrolysers, explains the cost considerations.“The main cost of hydrogen by electrolysis is the power cost. And if you have Euro20 per MW/h that results with the efficiency of conversion into one euro per kg. So that means if you pay 10 cents per kWhr, that would result in 5 Euros per kg just in power costs so we need cheap renewable electricity to produce cheap renewable hydrogen.”
Lowering Cost with Green Hydrogen
Cheap, renewable hydrogen produced from wind or solar power is becoming known as green hydrogen. “It is probably the key area where everyone is concentrating because it gives immediate decarbonisation and immediate value,” says Faiez Sallie, oil and gas practice leader at Mott MacDonald. He has no doubt that the green hydrogen model will be used to create decarbonised power systems. “Some of the main projects are the WindGas project in Falkenhagen in Germany, the HyStock in the Netherlands and then in Europe there are around 45 power to gas projects in development at this point in time.”
The challenge, he says is about ensuring that industry can collaborate to scale up these technically feasible projects and that the end users are being connected with the producers. This brings us on to considering one of the key challenges that the hydrogen industry must overcome in order to get this gas to the end users – the transportation and supply issue. It is not possible to simply send hydrogen through existing natural gas supply pipelines.
“The actual pipelines, many pipelines can be prone to stress corrosion or stress cracking and this is due to hydrogen embrittlement of the pipelines,” says Faiez.
The flammability of hydrogen is a key concern for the general public too. So how do we manage these risks? “From an industry point of view we are very familiar with the risks associated with hydrogen and the gas industry has been looking at putting safety measures in place for managing the risks associated with these different materials and gases,” says Chris De Beer. “In saying that yes there are additional risks that probably come into play with hydrogen, especially rolling it out in mass scale – the flammability and the ignition point is much lower than natural gas. You also need to store it at very high pressures if you want to store significant quantities of it so that needs to be taken into account.”
Safety Standards Established
So how does Hydrogenics, a company that has been making hydrogen for 70 years, manage that risk? “Hydrogen is explosive, it has high flammability and flammability range more than other gases that’s definitely true and therefore it is the first thing we need to address as an industry that is our responsibility’” says Arnaud. “We are dealing with many other gases all across different industries so why not hydrogen? We have been developing high redundant systems, safety equipment, over pressurised rooms and zones with hydrogen. And we have very strong and accurate measurement which are redundant and allow us to detect hydrogen presence much before we are going into an explosive mixture with air and hydrogen does not explode by itself – it needs an oxidant.”
Arnaud says that standards and safety equipment requirements vary around the world but that these are very well understood after years of experience. Hydrogen may not yet be the backbone of clean energy systems but it has been widely used in other industries such as for fertilizer production and around 70 million tonnes of it are produced every year.
But to really explore how hydrogen could transform energy systems, experts say we need more projects to scale the technology up and get the costs down. This is something that Andy Lewis of UK gas distribution network company Cadent knows all about. As a transmission company they want to know exactly how much hydrogen they can safely blend into their existing gas network without risking hydrogen embrittlement or forcing customers to change their behaviour. “HyDeploy is a project that is being hosted by Keele University. Cadent is leading the project along with our project partners. We are trying to prove that a hydrogen blend, so 20 percent volume or 7 per cent energy, can be injected into a working gas network and that will require no change from the customer. The hydrogen can be accepted by their boilers for commercial applications and they won’t have to go switching out any of their boilers or changing any of their habits so more or less they are decarbonising by making no change.”
Hydrogen with Carbon Capture
The project team have used an electrolyser in order to begin injecting hydrogen into Keele University’s gas grid. At the same time Cadent is also seeking funding from the industrial strategy challenge fund for a combined carbon capture storage and hydrogen production project called HyNet that will prevent 1 million tonnes of carbon being released into the atmosphere every year. “So what makes HyNet possible is the fact that we have got offshore fields in the East Irish sea that are due to be decommissioned and they are due to be decommissioned in the early 2020s and we are looking to repurpose those to hold CO2 and if we do that then we can have a large hydrogen production facility on the southern banks of the Mersey, and then we can supply a huge quantity of hydrogen to industry, a blend into our network and also to transport,” says Andy.
Andy says that sending the CO2 offshore can be done using existing pipelines serving the Hamilton and Lennox Gas Fields in Liverpool Bay. This is captured from the new hydrogen production plant, which uses another methane reformation process called autothermal reforming. A new 109km transmission system, made from 18 to 24-inch diameter high strength steel, will provide industrial users with hydrogen in place of natural gas. For local domestic gas customers HyNet will explore blending hydrogen with natural gas building on the work done in the HyDeploy project. Andy estimates that a small number of system entry points could provide a blended mix for around 2 million customers in the area.
Having taken the project through feasibility and into preliminary design, the next stage is the front-end engineering design or FEED stage, and a final investment decision will be made in 2022. If this is positive, then deployment is planned for 2025.
HyNet is also the UK’s first carbon capture usage and storage project and Andy says that combining CCUS, or CCS, with hydrogen, as explained by Chris Stark earlier in this episode, would give the UK a world leading advantage in deployment of this technology. Andy says that government should support a number of schemes that are planned in this space, to kickstart this industry and build UK expertise.
Reducing Costs to Boost Industry
One of the issues that this fledgling industry has to consider is how to bring down costs, and one of the proposals is building clusters around industrial hubs and ports where existing infrastructure can enable trading as well as the use of stranded renewables to produce hydrogen.
Mott MacDonald’s energy economist Guy Doyle points to this as being one of the ways that hydrogen could become cost competitive. “So what do I mean by stranded renewable energy? I mean renewable energy that is away from the main markets and is ultra-low cost. So here we are looking at solar in the desert, the best wind sites, then you electrolyze it, then you bring it through the logistics chain and in this case, you need to rely on the hydrogen carrier to get it there.”
From an economic perspective Guy points to industrial process heat as being a good market, as a competitive, low carbon alternative to natural gas but he finds that the biggest potential lies in another area – back up power. “This is the one I spend most of my time looking at. Hydrogen is the natural winner in long duration storage and back up in a low carbon world.”
To be truly cost competitive hydrogen has to get down to parity with electricity which when transmission costs are included sits somewhere between 8 and 12p per kWhr. Guy says this is equivalent to around £3 per kilo for hydrogen production and the industry is a long way above that today.
Policy to Unlock Potential
But for these projects to happen more direction is needed from government, which has so far failed to set out a strategy for hydrogen. Energy transformation in the past has required government support though policy levers like the renewables obligations and the creation of The Gas Council that drove the £500 million switch over from Town Gas to Natural Gas in the late 1960s. Similar leadership is needed now if the UK is going to meet its own obligations to the Paris Climate Agreement, let alone have any hope of exporting its expertise into other markets.
Increasing collaboration between the wide array of industry players, could be another way of facilitating progress in the hydrogen arena. Much like hydrogen is an energy vector bringing together disparate parts of the energy system, a new task force could prevent duplication and fragmentation in the industry and accelerate the technical and economic development required to scale up hydrogen production and operation. This is especially important as we start to see ever greater breakthroughs in hydrogen production that could push costs down further, from Stanford University where researchers achieved electrolysis of sea water, to developments in direct hydrogen production from sunlight.
So could hydrogen become a transformative element in decarbonising UK and global energy markets? Well the answer is clearly yes. But unless projects move ahead, the evidence base expands allowing hydrogen production costs to fall, it will fail to live up to its potential.
