Is Hydrogen the Fuel of the Future?
It's Friday. It's 24th November. I'm Anthony Day and this is the Sustainable Futures Report. Thank you for listening wherever you are in the world, and listeners to the last episode were in 40 different countries; predominantly the UK and the United States, but increasingly in Australia, (G’day - I’ll be there next month), regular listeners in Canada and a big hello to my one listener in the Cayman Islands. Maybe that's my bank manager on holiday. Thank you to my patrons. More about patrons at the end of this episode, and thank you to all those who have got in touch with suggestions and ideas.
This week I'm going to talk about hydrogen. The big question is,
“Is Hydrogen the Fuel of the future?”
The first supplementary questions are, “What will the fuel of the future look like? What characteristics must it have? What are we going to use it for?”
What characteristics must our fuel of the future have?
There are several undesirable characteristics of the fossil fuels that provide much of our energy at present, which is why we are considering moving away from them. The principal reason is pollution. Fossil fuels produce carbon dioxide when burnt; carbon dioxide is a greenhouse gas and increasing levels of greenhouse gases in the atmosphere are leading to climate change, or what some would prefer to call the climate crisis. Fossil fuels also emit particulates, which is really a fancy name for soot: microscopic fragments which pollute the atmosphere, which we all inevitably breathe in and which can cause long-term lung damage and disease.
There’s no doubt that fossil fuels have desirable characteristics which we would like our fuel of the future to share. For example, petrol and diesel are energy-dense, which means that just a small volume can contain enough energy to do a significant amount of work. It’s been calculated that one gallon of gasoline contains the energy-equivalent of between 2 days and 2 weeks of human labour, (depending on what the human is doing, and there is a very wide range of estimates - links on the blog.) Nevertheless, all that energy is concentrated in one container which anyone could carry.
I hesitate to say that fossil fuels are cheap, but at least they are affordable. Our ideal fuel must compete on price or show very clear advantages to justify a higher cost. Our ideal fuel must not emit greenhouse gases, particulates or other pollutants like sulphur dioxide and nitrous oxide, and depending on the application, it must be at least as energy-dense and portable as fossil fuels.
What about storage?
Coal, petrol, diesel and gasoil can all be relatively easily stored at ambient temperature and ambient pressures. Of course the right sort of container is needed to prevent leakage, fires or explosions, but this is all relatively low-tech. Natural gas is more demanding in that it has to be delivered by pipeline at carefully controlled pressure, but the national gas grid is well established and runs safely and reliably without any of us thinking about it much.
At this point I think we should talk about electric batteries which are becoming an increasingly important method of storing energy. There is a tremendous amount of research going in to improve batteries, but at the moment they are not nearly as energy dense as petrol or diesel. They also require conflict minerals in their manufacturer: materials that come from war-torn failed states, some of them with child miners guarded by child soldiers. And once the batteries reach the end of their lives there is much more than an empty metal tank to recycle. Let’s look at production and distribution.
How will our ideal fuel measure up on that?
Oil has a long-established supply chain between refineries and consumers. Industries can be served by rail tanker or pipeline. Home heating fuel is delivered by road tankers. Petrol stations are far less numerous than they used to be, but most motorists live within a mile or so of their nearest one. The other side of the refinery, the upstream side, can be more problematic. Crude oil can be delivered to the refinery by ship or by pipeline but the ultimate source of the oil is increasingly controversial. While new techniques mean that more oil can be recovered from reserves than was previously possible, oil companies have been forced to exploit wells in increasingly hostile environments like the Arctic regions and the deep oceans. It's not always successful, and BP's Deepwater Horizon is only one example of things which have gone spectacularly wrong.
The oil and the gas markets have been revolutionised by the spread of fracking in the United States. By injecting high-pressure water into the crevices in shale and oil-bearing rock, producers have been able to extract oil and gas. Not without controversy. Many claim that there are risks of polluting the water table and drinking water supplies. They claim that fracking for natural gas can release fugitive methane emissions, and methane is a significantly more potent greenhouse gas than carbon dioxide. (Some say 20 times as bad, some say 120 times.) Some countries, like France and Scotland have put a total ban on fracking. In England preliminary drilling has taken place and protesters have been arrested. It is expected that the Secretary of State will shortly give approval for production to start. Apparently the decision has been held over, because it was not considered to be a good idea to announce the approval during the recent COP 23 climate conference in Bonn.
Our ideal fuel should not cause GHG emissions from the production process, and ideally should be distributed using existing pipelines and tankers.
According to Wikipedia, 20% of energy is used in residential and commercial buildings and a further 26% by transport. The remaining 54% is consumed by industry.
Our ideal fuel should serve all those needs.
How does Hydrogen measure up?
First of all - is it clean?
Hydrogen releases energy either in an internal combustion engine - like the engine of a petrol car - or in a fuel cell. The internal combustion engine is attractive, because it’s existing technology and only needs a modification to the fuel delivery system. There's a company in the United Kingdom which will convert to your road vehicle all your stationary engine to run on hydrogen. For some reason they're based in Shetland, equidistant from Scotland, the Faroe Islands and Norway. Hydrogen burnt in an internal combustion engine is very clean. The process produces pure water and very low levels of nitrous oxides.
The fuel cell is a completely different technology from the internal combustion engine. It is fed with hydrogen and produces electricity, some heat and pure water. The most important difference between the fuel cell and the internal combustion engine running on hydrogen is that the internal combustion engine is about 20 to 25% efficient, whereas the fuel cell is closer to 60% efficient. Carmakers BMW and Ford have produced internal combustion engined cars running on hydrogen but Toyota has chosen to go with fuel cells. A small company in Wales, UK, has developed a fuel cell car with some quite innovative ideas. I strongly recommend you watch the video. Search for riversimple hydrogen cars, or find the link on the blog at www.sustainablefutures.report.
What about energy density?
Liquid hydrogen has a very high energy density. This is great for space rockets where it has been used successfully to blast them into orbit. The problem with using liquid hydrogen in other applications is that it boils at 20° Kelvin which is about -253°C. It takes vast amounts of energy to cool hydrogen to this level and masses of insulation to keep it cool.
Toyota’s Mirai fuel-cell car takes 5kg of hydrogen and needs to store it at 700 bar (that’s around 10,000psi) to reduce it to an acceptable volume. That gives a range of around 300 miles or just under 500 kilometres. Commercial vehicles; lorries, buses, trains can all use hydrogen. They can use bigger storage tanks which will still be much smaller in relation to the payload than that in a passenger car. Stationary engines or static fuel cells have far less constraint on space for fuel storage, so the tanks can be bigger and can operate at lower pressure.
Storing and distributing hydrogen
Storage and distribution are an issue. There are only three public hydrogen filling stations in the UK at present, although more are planned. The existing infrastructure of tankers and pipelines used for oil and natural gas can certainly not be used for hydrogen. [Unless the iron gas mains have been replaced with plastic] According to Wikipedia, “Hydrogen poses a number of hazards to human safety, from potential detonations and fires when mixed with air to being an asphyxiant in its pure, oxygen-free form. In addition, liquid hydrogen is a cryogen and presents dangers (such as frostbite) associated with very cold liquids. Hydrogen dissolves in many metals, and, in addition to leaking out, may have adverse effects on them, such as hydrogen embrittlement, leading to cracks and explosions. Hydrogen gas leaking into external air may spontaneously ignite. Moreover, hydrogen fire, while being extremely hot, is almost invisible, and thus can lead to accidental burns.”
The US Office of Energy Efficiency and Renewable Energy publishes guidance on hydrogen storage and related challenges.
There are two main processes for the production of hydrogen. The first is extraction from natural gas. Natural gas is principally made up of methane and the chemical formula is CH4, which means one carbon atom to four hydrogen atoms. Stripping out the hydrogen leaves the carbon which reacts with oxygen in the extraction process and produces CO2 or carbon dioxide. Thus a hydrogen engine or fuel cell can be almost completely clean in operation, but the CO2 emissions have been released at the point of hydrogen production. It's a similar argument to electric power. Electricity is totally clean at the point of use, but it may have come from a polluting power station.
The other process is electrolysis, which involves passing an electric current through water. Water is H2O, two hydrogen atoms to one of oxygen, and the process splits them apart. There are no greenhouse gas emissions, but electrolysis is not very efficient and the hydrogen produced can contain as little as 40% of the energy in the electricity used. This may make sense where there is excess renewable electricity, but it is a very inefficient use of electricity produced by a traditional gas, coal or nuclear-power station.
What it costs
The currently UK pump price makes the fuel cost per mile comparable with a petrol or diesel car, although hydrogen is significantly more expensive than gasoline at the pump in the US. Are very few hydrogen cars on the road at present, but the Toyota Mirai is on sale at £65,000. That's about US$85,000. It's an expensive car although it's designed to be a luxury car and is still less expensive than the Tesla Model S, their pure electric vehicle. At this stage Toyota prefer to lease the Mirai rather than sell it outright. Interestingly the River Simple hydrogen car company in Wales is planning the same approach.
How does hydrogen measure up?
- It’s almost totally clean and emission-free at the point of use.
- The cost of fuel is currently about the same per mile as petrol or diesel.
- A hydrogen car can be refuelled as quickly as a petrol car and much faster than an electric car.
- Current methods of production are either very inefficient produce greenhouse gas emissions.
- There is no distribution infrastructure at present, apart from three vehicle filling stations in the UK, and similarly small numbers in the United States and in some European countries.
- Hydrogen cannot be distributed using existing tankers or pipelines. These must be built specifically for transporting hydrogen.
On balance, hydrogen doesn’t look like a good idea, but there’s a whole lot more to this story.
Apart from Toyota; BMW, Ford, Mercedes, Nissan and many others are all working on hydrogen fuel cell cars. These companies are members of the Hydrogen Council and so are Shell, Total, Statoil, Mitsubishi and other major corporations. At COP23 in Bonn last week they claimed that hydrogen could power between 10 and 15 million cars by 2030. Clearly they expect the problems to be overcome. The Nikola Corporation is launching its hydrogen-powered Nikola One truck, with a million miles free hydrogen fuel. Do look at their website - nikolamotor.com/one - it’s very detailed.
There is promising research into new methods of extracting hydrogen cleanly from natural gas. It has been known that metallic catalysts can trap the carbon and prevent it from reacting to become CO2. The problem is that the surface of the metal soon becomes coated with carbon and absorption stops. Now scientists have developed a process which involves bubbling natural gas through a molten metal catalyst. The hydrogen is released and the carbon floats to the surface of the metal as a solid.
Other researchers have developed a solar-powered electrolysis system using cheaper materials for the electrodes and incorporating super-capacitor storage. No data is available yet on the efficiency of this process.
In Japan researchers have found a compound which allows them to create hydrogen from water using near infra-red light.
In January, in Brussels, Belgium, the Hydrogen and Fuel Cells Energy Summit takes place. Sadly I can’t go. Over two days, followed by site visits, they will be talking about
• Overview of the actual hydrogen and fuel cells market
• Latest technologies involved in the renewable sources
• Policy and regulations
• Power-to-gas solutions
• Decarbonisation of the energy sector
• Hydrogen storage improvements
• Security aspects in hydrogen production, storage and distribution
• Monetisation advice and partnership
• Hydrogen mobility applications
• Integration and standards
One of the conference partners is Hydrogenics, a Canadian company with branches across the world. They were also involved in last week’s Hydrail Symposium staged in Toronto. The Ministry of Transportation and rail operator Metrolinx invited industry leaders to take a look at how hydrogen fuel cell technology could potentially electrify the entire Ontario rail network. Without overhead wires. There was a live web cast of the event and the archive recording is still available on the website. Links to this and many other things that I've covered in this episode are on the blog at www.sustainablefutures.report as always.
The Hydrogenics company offers a whole range of energy solutions involving hydrogen. A link to their website is below.
And this is a very important part of the hydrogen story. I'm coming closer to home, to Leeds in West Yorkshire in United Kingdom.
Leeds City Gate - H21 is a plan to establish a hydrogen economy in Leeds.
Let me quote from the Executive Summary of the report:
“The H 21 Leeds City Gate Project is a study with the aim of determining the feasibility, from both a technical and economic viewpoint, of converting the existing natural gas network in Leeds, one of the largest UK cities, to 100% hydrogen.
The project has been designed to minimise disruption for existing customers and to deliver heat at the same cost as current natural gas to customers.
The project has shown that:
- The gas network has the correct capacity for such a conversion
- It can be converted incrementally with minimal disruption to customers
- Minimal new energy infrastructure will be required compared to alternatives
- The existing heat demand for Leeds can be met via steam methane reforming and salt cavern storage using technology in use around the world today
The project has provided costs for the scheme and has modelled these costs in a regulatory finance model.
In addition, the availability of low-cost bulk hydrogen in a gas network could revolutionise the potential for hydrogen vehicles and, via fuel cells, support a decentralised model of combined heat and power and localised power generation.”
Now that’s a vision!
Is hydrogen the fuel of the future?
What do you think?
I certainly wouldn’t rule it out.
And that's it for another week. I'm Anthony Day. Thank you for listening to the Sustainable Futures Report. By the way, I told you last week that I was going to commission some researchers to write articles for this podcast. I asked them to write about hydrogen. You should have seen the rubbish I got. It might have suited an encyclopaedia. Come to think of it, that's probably where they got it from. No, as usual, I have written and researched all this myself. If you like it please get in touch and let me know. If you don't like it please get in touch and tell me why. firstname.lastname@example.org
Next week we are in December and next week’s Sustainable Futures Report will be devoted to another element: this time it’s copper. The week after that, 8th December, we have an interview with George Monbiot which you certainly shouldn't miss. After that I'm going to take some time off until after Christmas. I expect you'll want some time off too.
If you're thinking of Christmas presents, well why don't you sign up as a patron of the Sustainable Futures Report? Just go to patreon.com/SFR where you’ll find all the details. I'm grateful to all my current patrons and their contributions to covering the expenses of running this podcast. You know who you are. Thank you all - wherever you are in the world.
And yes, that is it for this week. Have a great week.
I will catch up again on 1 December.
This is Anthony Day.
That was the Sustainable Futures Report.
That's all for now.
Cars and road vehicles
Read more at https://www.shropshirestar.com/news/motors/2017/11/20/car-manufacturers-say-hydrogen-could-power-10-to-15-million-cars-by-2030/#OoO20t2dSwtvgWuQ.99
Fuel Cell v Internal Combustion Engines
Organisations, Conferences and Plans