Which sectors are most suited to hydrogen, and which are not? For the answer, six academics from the UK and the Netherlands – Tom Baxter, Ernst Worrell, Hu Li, Petra de Jongh, Stephen Carr, and Valeska Ting – use their areas of expertise to neatly summarise hydrogen’s pros and cons in Road and Rail, Aviation, Heating, Electricity and Energy Storage, and Heavy Industry. Their general message seems clear: hydrogen is still very expensive, so it can be used primarily where there are no emissions-low alternatives, and where other advantages outweigh higher costs. Freight (trucks to trains) and aviation can benefit from liquid hydrogen’s very high energy density. Heavy industry needs the high temperatures that hydrogen can deliver better than electricity. But cars, heating, electricity and storage all have cheaper green alternatives meaning that hydrogen will only be a distraction, argue the authors.
Is hydrogen the lifeblood of a low-carbon future, or an overhyped distraction from real solutions? One thing is certain – the coal, oil and natural gas which currently power much of daily life must be phased out within coming decades. From the cars we drive to the energy that heats our homes, these fossil fuels are deeply embedded in society and the global economy.
But is the best solution in all cases to swap them with hydrogen – a fuel which only produces water vapour, and not CO₂, when burned? Answering that question are six experts in engineering, physics and chemistry.
Road and Rail
Hu Li, Associate Professor of Energy Engineering, University of Leeds
Transport became the UK’s largest source of greenhouse gas emissions in 2016, contributing about 28% of the country’s total.
Replacing the internal combustion engines of passenger cars and light-duty vehicles with batteries could accelerate the process of decarbonising road transport, but electrification isn’t such a good option for heavy-duty vehicles such as lorries and buses. Compared to gasoline and diesel fuels, the energy density (measured in megajoules per kilogram) of a battery is just 1%. For a 40-tonne truck, just over four tonnes of lithium-ion battery cells are needed for a range of 800 kilometres, compared to just 220 kilograms of diesel.
…Hydrogen fuel cells for freight, public transport
With the UK government set to ban fossil fuel vehicles from 2035, hydrogen fuel cells could do much of the heavy lifting in decarbonising freight and public transport, where 80% of hydrogen demand in transport is likely to come from.
A fuel cell generates electricity through a chemical reaction between the stored hydrogen and oxygen, producing water and hot air as a by-product. Vehicles powered by hydrogen fuel cells have a similar driving range and can be refuelled about as quickly as internal combustion engine vehicles, another reason they’re useful for long-haul and heavy-duty transport.
Hydrogen fuel can be transported as liquid or compressed gas by existing natural gas pipelines, which will save millions on infrastructure and speed up its deployment. Even existing internal combustion engines can use hydrogen, but there are problems with fuel injection, reduced power output, onboard storage and emissions of nitrogen oxides (NOₓ), which can react in the lower atmosphere to form ozone – a greenhouse gas. The goal should be to eventually replace internal combustion engines with hydrogen fuel cells in vehicles that are too large for lithium-ion batteries. But in the meantime, blending with other fuels or using a diesel-hydrogen hybrid could help lower emissions.
…Creating emissions-free hydrogen
It’s very important to consider where the hydrogen comes from though. Hydrogen can be produced by splitting water with electricity in a process called electrolysis. If the electricity was generated by renewable sources such as solar and wind, the resulting fuel is called green hydrogen. It can be used in the form of compressed gas or liquid and converted to methane, methanol, ammonia and other synthetic liquid fuels.
But nearly all of the 27 terawatt-hours (TWh) of hydrogen currently used in the UK is produced by reforming fossil fuels, which generates nine tonnes of CO₂ for every tonne of hydrogen. This is currently the cheapest option, though some experts predict that green hydrogen will be cost-competitive by 2030. In the meantime, governments will need to ramp up the production of vehicles with hydrogen fuel cells and storage tanks and build lots of refuelling points.
Hydrogen can play a key role in decarbonising rail travel too, alongside other low-carbon fuels, such as biofuels. In the UK, 6,049 kilometres of mainline routes run on electricity – that’s 38% of the total. Trains powered by hydrogen fuel cells offer a zero-emission alternative to diesel trains.
The Coradia iLint, which entered commercial service in Germany in 2018, is the world’s first hydrogen-powered train. The UK recently launched mainline testing of its own hydrogen-powered train, though the UK trial aims to retrofit existing diesel trains rather than design and build entirely new ones.
Aviation
Valeska Ting, Professor of Smart Nanomaterials, University of Bristol
Of all of the sectors that we need to decarbonise, air travel is perhaps the most challenging. While cars and boats can realistically switch to batteries or hybrid technologies, the sheer weight of even the lightest batteries makes long-haul electric air travel tricky.
Single-seat concept planes such as the Solar Impulse generate their energy from the sun, but they can’t generate enough based on the efficiency of current solar cells alone so must also use batteries. Other alternatives include synthetic fuels or biofuels, but these could just defer or reduce carbon emissions, rather than eliminate them altogether, as a carbon-free fuel like green hydrogen could.
…Liquid hydrogen has x3 the energy density of jet fuel
Hydrogen is extremely light and contains three times more energy per kilogram than jet fuel, which is why it’s traditionally used to power rockets. Companies including Airbus are already developing commercial zero-emission aircraft that run on hydrogen. This involves a radical redesign of their fleet to accommodate liquid hydrogen fuel tanks.
An artist’s impression of what hydrogen-powered commercial flight might look like. Airbus
There are some technical challenges though. Hydrogen is a gas at room temperature, so very low temperatures and special equipment are needed to store it as a liquid. That means more weight, and subsequently, more fuel. However, research we’re doing at the Bristol Composites Institute is helping with the design of lightweight aircraft components made out of composite materials. We’re also looking at nanoporous materials that behave like molecular sponges, spontaneously absorbing and storing hydrogen at high densities for onboard hydrogen storage in future aircraft designs.
…Airport infrastructure
France and Germany are investing billions in hydrogen-powered passenger aircraft. But while the development of these new aircraft by industry continues apace, international airports will also need to rapidly invest in infrastructure to store and deliver liquid hydrogen to refuel them. There’s a risk that fleets of hydrogen aeroplanes could take off before there’s a sufficient fuel supply chain to sustain them.
Heating
Tom Baxter, Honorary Senior Lecturer in Chemical Engineering, University of Aberdeen and Ernst Worrell, Professor of Energy, Resources and Technological Change, Utrecht University
If the All Party Parliamentary Group on Hydrogen’s recommendations are taken up, the UK government is likely to support hydrogen as a replacement fuel for heating buildings in its next white paper. The other option for decarbonising Britain’s gas heating network is electricity. So which is likely to be a better choice – a hydrogen boiler in every home or an electric heat pump?
…Heat pumps are much cheaper than hydrogen-fuelled boilers
First there’s the price of fuel to consider. When hydrogen is generated through electrolysis, between 30-40% of the original electric energy is lost. One kilowatt-hour (kWh) of electricity in a heat pump may generate 3-5 kWh of heat, while the same kWh of electricity gets you only 0.6-0.7 kWh of heat with a hydrogen-fuelled boiler. This means that generating enough hydrogen fuel to heat a home will require electricity generated from four times as many turbines and solar panels than a heat pump. Because heat pumps need so much less energy overall to supply the same amount of heat, the need for large amounts of stored green energy on standby is much less. Even reducing these losses with more advanced technology, hydrogen will remain relatively expensive, both in terms of energy and money.
So using hydrogen to heat homes isn’t cheap for consumers. Granted, there is a higher upfront cost for installing an electric heat pump. That could be a serious drawback for cash-strapped households, though heat pumps heat a property using around a quarter of the energy of hydrogen. In time, lower fuel bills would more than cover the installation cost.
Heat pumps, like this one, are a better bet for decarbonising heating. Klikkipetra/Shutterstock
…Gas grid upgrades needed first
Replacing natural gas with hydrogen in the UK’s heating network isn’t likely to be simple either. Per volume, the energy density of hydrogen gas is about one-third that of natural gas, so converting to hydrogen will not only require new boilers, but also investment in grids to increase how much fuel they can deliver. The very small size of hydrogen molecules means they’re much more prone to leaking than natural gas molecules. Ensuring that the existing gas distribution system is fit for hydrogen could prove quite costly.
…More, better, alternatives to hydrogen
In high-density housing in inner cities, district heating systems – which distribute waste heat from power plants and factories into homes – could be a better bet in a warming climate, as, like heat pumps, they can cool homes as well as heat them.
Above all, this stresses the importance of energy efficiency, what the International Energy Agency calls the first fuel in buildings. Retrofitting buildings with insulation to make them energy efficient and switching boilers for heat pumps is the most promising route for the vast majority of buildings. Hydrogen should be reserved for applications where there are few or no alternatives. Space heating of homes and buildings, except for limited applications like in particularly old homes, is not one of them.
Electricity and Energy Storage
Petra de Jongh, Professor of Catalysts and Energy Storage Materials, Utrecht University
Fossil fuels have some features that seem impossible to beat. They’re packed full of energy, they’re easy to burn and they’re compatible with most engines and generators. Producing electricity using gas, oil, or coal is cheap, and offers complete certainty about, and control over, the amount of electricity you get at any point in time.
Meanwhile, how much wind or solar electricity we can generate isn’t something that we enjoy a lot of control over. It’s difficult to even adequately predict when the sun will shine or the wind will blow, so renewable power output fluctuates. Electricity grids can only tolerate a limited amount of fluctuation, so being able to store excess electricity for later is key to switching from fossil fuels.
…Big cost reductions needed
Hydrogen seems ideally suited to meet this challenge. Compared to batteries, the storage capacity of hydrogen is unlimited – the electrolyser which produces it from water never fills up. Hydrogen can be converted back into electricity using a fuel cell too, though quite a bit of energy is lost in the process.
Unfortunately, hydrogen is the lightest gas and so it’s difficult to store and transport it. It can be liquefied or stored at very high pressures. But then there’s the cost – green hydrogen is still two to three times more expensive than that produced from natural gas, and the costs are even higher if an electrolyser is only used intermittently. Ideally, we could let hydrogen react with CO₂, either captured from the air or taken from flue gases, to produce renewable liquid fuels that are carbon-neutral, an option that we’re investigating at the Debye Institute at Utrecht University.
Heavy Industry
Stephen Carr, Lecturer in Energy Physics, University of South Wales
Industry is the second most polluting sector in the UK after transport, accounting for 21% of the UK’s total carbon emissions. A large proportion of these emissions come from processes involving heat, whether it’s firing a kiln to very high temperatures to produce cement or generating steam to use in an oven making food. Most of this heat is currently generated using natural gas, which will need to be swapped out with a zero-carbon fuel, or electricity.
Furnaces in the steel industry are generally powered by fossil fuels. Rocharibeiro/Shutterstock
…Case study: ceramics manufacturing
Let’s look in depth at one industry: ceramics manufacturing. Here, high-temperature direct heating is required, where the flame or hot gases touch the material being heated. Natural gas-fired burners are currently used for this. Biomass can generate zero-carbon heat, but biomass supplies are limited and aren’t best suited to use in direct heating. Using an electric kiln would be efficient, but it would entail an overhaul of existing equipment. Generating electricity has a comparably high cost too.
Swapping natural gas with hydrogen in burners could be cheaper overall, and would require only slight changes to equipment. The Committee on Climate Change, which advises the UK government, reports that 90 TWh of industrial fossil fuel energy per year (equivalent to the total annual consumption of Wales) could be replaced with hydrogen by 2040. Hydrogen will be the cheapest option in most cases, while for 15 TWh of industrial fossil fuel energy, hydrogen is the only suitable alternative.
Hydrogen is already used in industrial processes such as oil refining, where it’s used to react with and remove unwanted sulphur compounds. Since most hydrogen currently used in the UK is derived from fossil fuels, it will be necessary to ramp up renewable energy capacity to deliver truly green hydrogen before it can replace the high-carbon fuels powering industrial processes.
Green hydrogen is only part of the solution
The same rule applies to each of these sectors – hydrogen is only as green as the process that produced it. Green hydrogen will be part of the solution in combination with other technologies and measures, including lithium-ion batteries, and energy efficiency. But the low-carbon fuel will be most useful in decarbonising the niches that are currently difficult for electrification to reach, such as heavy-duty vehicles and industrial furnaces.
***
Tom Baxter is an Honorary Senior Lecturer in Chemical Engineering, University of Aberdeen
Ernst Worrell is Professor of Energy, Resources and Technological Change, Utrecht University
Hu Li is an Associate Professor of Energy Engineering, University of Leeds
Petra E. de Jongh is Professor of Catalysts and Energy Storage Materials, Utrecht University
Stephen Carr is a Lecturer in Energy Physics, University of South Wales
Valeska Ting is Professor of Smart Nanomaterials, University of Bristol
This article is republished from The Conversation under a Creative Commons license. Read the original article.
I don’t get why professor Hu Li from Leeds University keeps talking about hydrogen trucks for 800 km range. Apparently his knowledge is not state of the art; listen to the interview between Michael Liebreich and Auke Hoekstra. It’s wrong to compare 4 tons of batteries with just 220 kg of diesel. The combustion engine and auxilliaries weigh extra compared to electric. Net weight for batteries is more like 2 tons and declining. Also, trucks aren’t necessarily weight constrained, but can be volume constrained.
https://www.youtube.com/watch?v=ZmeaqJc-jYg&ab_channel=CleaningupwithMichaelLiebreich
The comments re rail and freight are misplaced. The performance of hydrogen, fuel cells and batteries may be relevantt for some very niche applications. The Tare to gross ratio of freight requires a much more powerful energy source. Hydrogen does not have a comparable energy density to diesel fuel, it is expensive and polluting to produce from methane. Electrolysis is equally compromised. Using intermittent wind power is not a viable option
Electrification on rail is a well developed technology set and could be made more effective by lowering the front end costs of wiring up (definitely do-able). The advantages of a wired up network for freight and passenger are clear.The exotics as discussed are an irrelevance in tems of coist competitiveness, life costs and delivered performance capabilities.
Compressed Air is a much more friendly option…. than explosive Hydrogen or Waste Creating-Limited Life Electric Batteries. If Waste Heat is recovered/used then the lower efficiency “penalty” of CA can greatly offset this handicap….. and remember there are no (very) expensive Batteries or explosive Hydrogen to handle….
The lower costs of CAV’s (Comoressed Air Vehicles) needing no battery replacements and more than offsets the higher cost of “recharging” the vehicle (due to lower “apparent” Efficiency) …
The Hindenberg (like The Titanic) Disaster should remind all that “Techno-Arrogance” and handling explosive Hydrogen for mobile applications… is inviting repeating ones past mistakes..
Hydrogen as an Industrial “fuel” is fine… but not so sure about mobile applications.
Also remember the World requires only 1Million km2 of AgriVoltaics on the existing 15MillionKm2 of Farmland to generate ALL ITS ENERGY NEEDS…. a whopping 200,000 TWhrs/yr by a 150TW AgriVoltaic System… no problem of either Energy or Land Supply here….
Therefore, the lower efficiencies (of CA) requiring a marginally larger AgriVoltaics System while ensuring Zero Pollution… is a …. No-Brainer…. may I suggest…
Thanks for the comprehensive overview. I would like to make some minor remarks regarding the statements dealing with heat pumps. The assessment is probably correct for UK but not for countries where the temperatures are much lower in winter time – so below – 4° C. Basically the following remarks are valid for air sourced heat pumps. Below – 4° C the COP (coefficient of performance) is lowered to 1 (instead the mentioned 3-5, whereas 5 is really optimistic) – which means one generates heat directly with electricity. So if air sourced heat pumps are located somewhere in cold regions, and there are thousands and thousands of them in a cold vale , one will need to reinforce the electricity grid which is transporting the electricity to the vale and futher on to the heat pumps. Don’t forget all of them need at the same time electricity despite the heat reservoir of the building itself, this means one needs high investments in the reinforcement of the upstream electricity grids (including high voltage) . Besides in times of lulls – in particular during nights – one will need additional power plants to generate the required additional electricity. These power plants will need fuel gas – hopefully hydrogen in the mid to long term – but still high additional investments are needed into the gas grid as well. On top, older existing heating systems (radiator systems) are designed for inlet temperatures of + 90°C and return temperatures of + 70°C. Heat pumps provide inlet temperatures of “just” + 42° – 45°C and return temperatures of 37° C (or so). With such temperatures one simply can’t heat the existing buildings. So additional huge investments are needed for the thermal insulation of such buildings. In addition one has to mention that the installation of air sourced heat pumps in cities is not that easy because of space restrictions – in particular in old rented apartments. In case one would avoid such restrictions – caused by air sourced heat pumps – one can use water/ground sourced heat pumps but such heat pumps are much more expensive AND even more important, one needs a lot of space to lay the heat collectors in the ground or to drill for water. So much the worse if you are located somewhere in a cold narrov vale in the Alps. One simply doesn’t have the space for the collectors and if the house is an old one, you can’t start to dig up the plot – even if the plot were big enough. To drill a hole for water is probably not possible because of the solid rocks below the layer of earth. Sorry for being that critical but these are facts. Best regards
The changes you refer to are ALL PART of the upgrade from the existing 7TW, 25,000 TWhrs/yr Global Fossil based Electric Grid…. to a 150TW, 200,000TWhrs/yr FULLY SOLAR POWERED ENERGY CUM STORAGE SYSTEM… remember as sale of Electricity goes… UP… so will the infrastructure to support it…. and as the sale of Fossil Fuels goes down… the support infrastucture (Oil/Gas Wells, Refineries, Mines, Pipelines rtc… go DOWN….
The Users of Energy (EV’s, Industry etc…) will also have to convert including use if HeatPumps with/without Electric Heaters…
REMEMBER WE ARE UNDOING THE 200+YEAR HARM DONE BY THE INDUSTRIAL AGE ….. POLLUTION… HOPEFULLY BY 2050…. ALL THIS IS FOR OUR…. GRAND CHILDREN…
Why all of these professors are avoiding give a minimum reference to the BLUE H2, generating it from NG and capturing / storing the CO2?.
Why if there are licensees, experiences, techonology and enough knowledge and the option is far cheaper than the “pure” green one?.
“How many years will it take for man to learn…. that too many people have died… the answer my friend… is blowing in the wind… the answer is blowing in the wind”….
The above was written/sung by Bob Dylan in the USA in the 1960/70’s during the Vietnam War.
Today we are facing a “GLOBAL WAR” against Pollution that kills 8+ Million/yr…. about the same as during WWII (believe it or not..)… with 250Million DALY (Disability Adjusted Life Years) of Human Suffering…. much much more than WWII wounded… too…
The major cause of Pollution are Fossil Fuels in Power Generation, Transportation, Industry and even HVAC too. NUCLEAR WASTE PROMISES us to leave behind a legacy of Nuclear Waste for 100,000+ years in
to the future…..
…. so the answer to your query is ” when will we ever learn.. too many people have died” due to Pollution and Fossil Fuels…. or maybe “One day you will join us”… as John Lennon would have said…
Proponents and Users of Fossil Fuels gave had a “great party” for the last 200+ years and destroyed the lives of hundreds if millions…. and continue to wallow in these killings…
In the past…. except for Nuclear (which promised… then failed… to leave no Radioactive Waste behind) Fossil Fuels were the ONLY Energy Source available.
However…. The “Energy/Pollution” World has been turned upside down thanks to economical PV Panels in the last decade and more.
Mankind is really fortunate, today, to have a Green, Sustainable, Non-Polluting Technology that can also eliminate the curse if the 200+ year old Industrial Age…. Pollution…. WHY IS MAN NOT EMVRACING THIS BENIGN ENERGY SOURCE RATHER THAN POLLUTING (MOSTLY) FOSSIL FUELS.
To put things in perspective…. Mankinds Global Energy (in the form of Electricity) needs in 2050 is about 200,000 TWhrs (20MWhrs/pp/yr…. 10 Billion Population) and would require a 150TW Solar System. These PV Panels will require about 1 Million km2 are sun exposure… with TODAYS TECHNOLOGY.
The above PV Panels can EASILY be accomodated on ONLY ~6% of the 15Million km2 of Agricultural Land…. using the AgriVoltaics (AV)Technology WITHOUT compromising Food Production.
[ In AV one places AV/PV Panels on AV Structures about 10-20ft above the Farmland below. This allows “dual-use” of fertile agricultural land… as it Generates Electricity from the AV roofs while growing food etc… below… AT THE SAME TIME).
As one can see…. the “Supply Side” of Energy can readily be met with TODAYS TECHNOLOGY by merging Agriculture and Solar PV Panels… no need for ANY SPACE TECHNOLOGY (Oooops…. Just as a reminder… PV Panels were “developed” for the NASA Space Program in the 1960’s… so here you have Space Technoligy behind AV… after all…)..
So…. with the Supply Side readily resolved…. with lots and lots of margin… elbow room.. etc… why use ANY POTENTIALLY POLLUTING FUELS (including Nuclear) AT ALL…
All “Colors of the Rainbow” Gases, Fuels etc…. have NO PLACE IN A ZERO POLLUTION WORLD OF OUR GRAND CHILDREN…. and are just ….Trojan Horses…. designed to PROTECT FINANCIAL ASSETS RATHER THAN HUMAN LIVES AND SUFFERING FROM POLLUTION….. ASAP.
Those still ADDICTED TO FOSSIL and OTHER POLLUTING FUELS… I say… “I hope that someday you will join us” … (is that John Lennon moving in his grave…???).
I can´t answer what is no based on data. I´ve no time for propaganda or endless discussions about ideologic poisons.
Have you ever tried to see the data behind Einsteins E=mc2… so should you ignore nuclear power bevause you have not “seen or understood” the data behind it…. Anyways….
“The Data” is simple….. for 2050…
• Estimated Annual Global Energy (in the form of Electricity) needs…. 20,000KWhr/person/yr…(one has to estimate as we are still 30 years away from “Real Data”).
• Estimated Global Population… 10 Billion.
• 20,000KWhrs X 10 Billion = 200 TWhrs/yr….
• System Size… 150TW…. @ 1333W/W/yr… (Global ramge varies from 1200-1500W/W/yr….
Do…. there is your data…. for 2050… believe it or not…. hope it helps… you DONOT HAVE TO RESPOND… it is upto you to “do your research” and get your Data… I also donot have time to prove E=mc2 to one and all… (actually I tried to understand the Physics behind this… and tried.. and tried… and failed… jyst FYI…).
The “Truth” is very very very elusive…. a man called Gautam Buddha tried to find “The Truth” abput 2500 years back… the rest is history…. I am NOT A BUDDHA I can assure you…. so what I have provided is good enough for me after reviewing hundreds of publications for many many years…
But one thing is clear and evident tp me…. Fossil Fuels when burnt…. Kill someone… somewhere… just like I believe the Earth is round (even though The Flat Earth Society exists)…
I have NO AGENDA OR PROPOGANDA… and consider your insinuation…. quite insulting, patronizong and derogtatory… just triyng to stop the 8.5 Million Pre-Mature Deaths Annually and 250 Million DALY of Suffering… maybe…. “one day you will join us”….
Is it true that: “Hydrogen fuel can be transported as liquid or compressed gas by existing natural gas pipelines”? I believe pure hydrogen is too corrosive for existing natural gas pipelines, which would necessitate building new pipelines
No. H2 is not corrosive. Only a very high temperature and pressure it develops intergranular inclusion and cracking. I would say that gas H2 can be transported in existing gas pipelines (subjected to clear safety on materials and conditions) without major risks, being easily separated from NG CH4. I don´t know abbout real pipelines transporting LNG (liquid natural gas) out of short sections on or around liquefaction and gasification plants.
Major or Minor Risks are…. I would think… is unacceptable for an “explosive gas” like Hydrogen…. take “short cuts”… like replacing Helium with Hydrogen in the Hindenberg… and be preprared to face the consequences. In case of The LTA (Lighter Than Air) Industry…. total shutdown….
I was not born during the Hindenberg era…. but I feel those Trans-Atlantic Cruises must have been…. super enjoyable and relaxing…. all destroyed because of a “minor..???” risk… ???
Always better tp be SAFE THAN SORRY…. I would think….
Many Piwer Plants around the Globe use Hydrogen to reduce windage losses…. perhaps you can “research” how Hydrogen is handled and their safety record… Best of luck….
About twenty years back we proposed using (Natural) Gas Pipelines for Coal Gas…. much more similar to Natural Gas than Hydrogen.
Sure enough, we soon found out that these Gas Pipelines were not very flexible.
Further investigation showed that no one had patented a Coal Gas Pipeline and after “due diligence” we filed a Patent Application and obtained the one year provisional “reservation” for this propisal from the US Patent Office.
We decided to “drop the idea” as we would NOT be able to protect ourselves / our patent easily…. and that was it….
I am telling you this…. because Natural Gas (and other) Pipelines generally have very limited Operating Boundaries …. unless major modifications… mostly of non-metals (gaskets, seals, valves, compressors etc..) are carried out.
So…. if you want to have a Hydrigen National/International Pipeline…. be prepared to “start from scratch” … except of course ROW (Right if Way)… which could still face major Public Hearing headaches…
Hope this helps out…. somewhat…
Good summary. However, it is missing a discussion of the other carbon-free energy carrier, which is particularly applicable to space heating: hot water.
Back during the oil shocks of the 1970s, in order to move away from oil heat, the US deployed our natural gas infrastructure. Many other countries deployed district heat networks instead. Heat networks use hot water pipes (formerly steam pipes) to supply space heating in homes and businesses. They can theoretically carry heat from any primary energy source, but most popular are geothermal, biomass, industrial waste heat, industrial-sized water-sourced heat pumps, and especially combined-heat-and-power thermal electrical production. China is starting to replace coal-fired heat with clean and sustainable nuclear heat in heat networks in their northern cities.
Heat networks can employ insulated tanks at the building, neighborhood, or city scale for low cost energy storage.
Compared to heat networks, electric heat pumps have numerous disadvantages. Heat is a very seasonal demand, with strong daily cycles, so their incremental load is often carried primarily by less efficient fossil fuel fired peaking power plants. For grids that are partly coal-fired, heat pumps are particularly polluting. The air-source out-door unit is noisy; ground source equipment is expensive and hard to maintain.
Heat networks main disadvantage is that they are a decarbonization solution which requires that we work together as a community. In other words it mirrors the climate change problem.
I dont recognise the issues with air sourced heat pumps, they are really quite quiet, realively easy to retrofit.
They certainly increase the requirement for electricity but there is twice as much windpower in the winter as the summer. Wind power is inherently variable, and storage very difficult.
Wind is still the way to go but with natural gas turbines/Allam cycle as back up with CCS or ideally CCUS.