by Udo Pollmer June 18, 2024
Now that Germany has decided to end its nuclear power industry, it can preserve all its radioactive nuclear waste for future generations because no plants are allowed to be operated to dispose of it. Now a new energy source must also be found. The pig that is now being herded through the media villages is called hydrogen. The German government wants...
...to create a gigantic industry; Germany is to become the "world market leader" "in an absolutely key technology of the 21st century: hydrogen technology".1
So far, hydrogen has mainly been produced from methane. But how useful is it to produce hydrogen from natural gas in order to refuel cars that could also run on methane? The electrolysis of methane produces considerable amounts of CO2 that nobody needs. Now the scene is celebrating the production of hydrogen from water as the long-awaited stroke of genius. After all, there is plenty of water. If energy is required, hydrogen is allowed to react with atmospheric oxygen in a fuel cell in a controlled manner. This produces water - and electricity. We use it to power emission-free electric cars and heat insect farms.
However, splitting water electrolytically into hydrogen (H2) and oxygen (O2) requires a lot of energy. There is a big green devil in this tiny detail: splitting requires much more electricity than the fuel cell generates later. If you factor in the technical losses, you only get back a third of the energy used.2 From an ecological point of view, it is probably better to fire the fireplace directly with banknotes.
Electrolysis is only reasonably effective if very high temperatures are available. Modern nuclear power plants, such as molten salt or dual fluid reactors with their 700° to 1000° C steam, would provide the ideal conditions for high-temperature electrolysis. Without them, an energy transition to a hydrogen economy is doomed to failure anyway.3
A technical nightmare
The hurdles of high-temperature electrolysis to produce hydrogen are high. Atomic hydrogen penetrates the cathode and destroys it.4,5 The elemental oxygen in turn dissolves the coating on the anodes.6,7 At high temperatures, which are essential for economic efficiency, corrosion increases dramatically.8 This is why feverish research is being carried out into new electrolysis systems. The solid oxide fuel cell, which works like a fuel cell in reverse gear, has raised the most hope. However, its success so far has been rather modest.9,10
The physics and chemistry of electrodes are still not fully understood. It is therefore hardly surprising that "significant neutron and alpha-particle emissions" have even been measured in experiments on electrodes. The number of neutrons increased tenfold compared to the background radiation. The number of alpha particles doubled.11 The loss of mass at the electrodes was offset by an equal amount of newly formed elements. Physicists refer to this as spallation.12,13 In this respect, high-temperature electrolysis must also be examined to determine whether radioactive elements are formed by spallation followed by transmutation.14,15
Spallation
In nature, cosmic radiation is the most important cause of spallation. It consists mainly of very fast, high-energy protons, which preferably originate from the sun. When the radiation hits an atom, it is torn into pieces. This creates new atoms, so-called cosmogenic nuclides. As a result, considerably more products of spallation are inhaled in the mountains than by the sea. The nuclides reach the earth with rain or dust. The formation of new elements through spallation takes place right into the soil. There, the atoms that occur in rocks and soils are shattered. (See Bon appétit of September 2023: Physics: treacherous isotopes)
Artificial spallation is the bombardment of a heavy atomic nucleus such as lead with a very fast proton using technical means such as particle accelerators. This causes the nucleus to break apart, ejecting around 20-30 neutrons per atom. These neutrons are then available for the production of fuel such as uranium-233.
The transformation of one element into another is called transmutation, e.g. by spallation with neutrons. If this results in an unstable atomic nucleus, it decays into smaller fragments. On the other hand, radioactive elements can be converted into stable atomic nuclei. Medical radionuclides are also usually obtained by transmutation. If, for example, uranium-233 is created from thorium-232 using a neutron, it takes weeks for the transmutation to be completed through all intermediate stages.
The problems of the hydrogen economy are not limited to the electrodes.16 The gas causes microcracks in the pipes, which open the way for the tiny hydrogen molecule to penetrate the material.17 As a result, even hardened stainless steel becomes brittle and thus represents a source of danger.18 Under mechanical stress, as is unavoidable in the planned expansion of a nationwide distribution network, at high pressures such as those required to transport H2 over long distances and with strong temperature fluctuations, hydrogen penetrates the metal all the more quickly. 16,19
Fire without flame
In the event of leaks, e.g. due to embrittlement, there is a risk of fire. With 4 % hydrogen in the air, there is explosive oxyhydrogen. Hydrogen fires differ from "ordinary" fires: When petrol or diesel leak, they collect near the ground. Hydrogen is the lightest element, and in the event of a leak, the gas quickly spreads upwards. Even a spark of static electricity from a finger can trigger an explosion. The flame burns invisibly and it is difficult to localise the actual "fire".20 According to the safety data sheet, a "water jet is unsuitable for extinguishing", with "CO2 fire extinguishers there is a risk of electrostatic charging" - bang!
This is what happened at the Fukushima nuclear power plant. When the cooling system failed due to the tsunami, the heat split the water vapour into oxygen and hydrogen. This vapour collected under the reactor dome. When it exploded and blew off the roof, the contents of the reactor were released into the sea by air. Three reactors were destroyed in this way.21,22 This was not an isolated incident: the reactor at Three Mile Island (1979) was blown up by a hydrogen explosion, as was the one at Chernobyl (1986).23,24 In addition, there are many other serious "incidents" around the world.25,26
The often-mentioned 2,500°C is by no means necessary for the formation of hydrogen. In the presence of zirconium, a metal that is widely used in reactors, 1,000°C is sufficient.27-30 In Fukushima, tens of thousands of cubic metres of H2 .21 Hydrogen explosions and core meltdowns are two sides of the same coin. The quantities released during normal operation are minimal and are automatically removed with recombiners.31 Thanks to the now recognised explosive nature of H2 formation in the event of an accident, safety requirements have been tightened.
Looking into the tubes
How can this dramatic scenario be reconciled with the fact that hydrogen has long been used for industrial syntheses, such as the production of steel, petrol, fertiliser (ammonia) and foodstuffs such as margarine? Germany also already has hydrogen pipelines with a total length of hundreds of kilometres, the oldest of which was laid in 1938. So you should have experience.
However, this should not be overestimated. Until now, hydrogen has been produced from methane, crude oil or coal using steam reforming. However, the production and distribution of hydrogen from water to replace the existing gas industry, whose pipeline network is over half a million kilometres long, is a completely different dimension.32
The few H2 pipes connect selected industrial companies that are used to handling category 1A hazardous substances. Some of their pipes have a diameter of 11 centimetres.33 It is not known how high the pipe losses are. Hydrogen delivers the most energy in terms of mass, i.e. per kilo. Nobody should be fooled by this and believe that 1 litre of hydrogen also delivers more energy than a litre of petrol. It is exactly the opposite: liquid or cryogenic hydrogen requires three times as much volume as petrol with the same energy content.8 This is why large pipe cross-sections and huge tanks are required.
Pipes with a clear width of at least 60 cm and suitable for compressed, liquid or cryocompressed hydrogen are required. In the latter case, we are talking about temperatures of minus 250°C and pressures of up to 1000 bar.34,35 The industry is now focussing on this cryocompressed hydrogen, a mixture of liquid and gaseous H2 as a supercritical fluid, also in order to be able to transport it long distances over land.
Cryocompressed hydrogen must always be extremely cooled. If the temperature rises, the pressure increases and the pipe can explode. The required insulation can only be achieved with vacuum tubes - as with thermos flasks - or, more precisely, with high-vacuum tubes. If they are defective at even one point and air penetrates, there is also a risk of explosion.
No longer completely tight
The Ministry of Research wants to cover Germany extensively with pipelines and an extensive distribution network: "A hydrogen core network over 11,000 kilometres long is to ... connect all major hydrogen feeders with all major consumers by 2032. In addition, the hydrogen refuelling station network is to be extensively expanded."36
The ambitious goal is to utilise old natural gas pipelines. Even though defects in gas pipelines have decreased by 90 % since 1990, according to the industry association DVGW37 , the gas industry still has to contend with methane leaks along its infrastructure: "The operators ... are sometimes only insufficiently aware of existing leaks," complains Deutsche Umwelthilfe based on its own measurements.38 In addition, natural gas pipelines become mouldy over time. To clean the dirt out of the pipes, they are regularly pigged. Hydrogen, however, must be extremely pure for fuel cells.
Compared to tiny hydrogen, methane is a huge molecule and therefore easy to control in terms of materials. Due to this difference in size, it is practically impossible to transport hydrogen in natural gas networks unless the pipes are dug out beforehand and lined with a plastic - one that politicians have declared war on: plastic based on fluorocarbons.39 In order to slow down the leakage from natural gas pipes, according to energy politicians, they should not transport the pure gas, but should first mix the gas with methane or oxygen. But then it must be thoroughly purified of its additives before use. This costs extra energy.
Any scale
The risks involved in transporting hydrogen in natural gas pipes can be minimised by using a lot of energy to convert the laboriously produced hydrogen into ammonia. The process requires high temperatures of 300-550°C and pressures of 200-350 bar.40 At the destination, it is split back into hydrogen by cracking, which is an energy-intensive process. Subsequent thorough purification is also required here in order to be able to operate fuel cells.
The eco-scene is calling for ammonia production to transport hydrogen in order to fight it vehemently at the same time: when ammonia is used as a nitrogen fertiliser for bread wheat or potatoes. The energy consumption for its production is irresponsibly high, one per cent of all "greenhouse gases" worldwide are caused by the production of nitrogen fertiliser.41 Yet mankind owes a considerable part of its food supply to this fertiliser. The Federal Environment Agency has issued a mandatory warning: ammonia endangers "human health" and damages "plants and ecosystems".42 It would probably be better to harvest feed wheat for the pig trough instead, as it requires less nitrogen.
Ahoy!
In sobering words, the industry magazine electrified has this to say: "Traditional natural gas pipelines are not tight enough, meaning that large quantities of the substance would be lost over distance. If the hydrogen is mixed with the natural gas, which would reduce the losses, it can hardly be separated later if required. Pressurised hydrogen pipelines are only likely to become available in the next decade. The hydrogen gas at German hydrogen refuelling stations therefore currently mostly comes by lorry. This is not very efficient ... A significant fleet of fuel cell cars cannot be refuelled in this way."43
As Germany produces too little hydrogen, it will have to import most of it in the foreseeable future. Transport by ship is possible in principle, but according to the expert it is "years away from being an established, commercial, and dependable method for transporting large quantities of hydrogen".35 The gas must first be compressed, cooled down and liquefied to -253°C. The energy required for compression to 700 bar is approx. 12% of the energy content of the gas, and approx. 20% for liquefaction.
The need to keep liquid hydrogen at very low temperatures throughout storage, transport and handling again costs energy and increases infrastructure costs - e.g. for cryogenic storage tanks, pipework and other equipment. In addition, there are considerable boil-off losses if gas is produced during transport. This must be drained from the tanks to prevent them from bursting due to overpressurisation. After landing, the hydrogen is heated and converted back into gas form, which again requires energy.34,35
It's not just nuclear power stations that explode from hydrogen, ordinary H2 refuelling stations can also be destroyed by oxyhydrogen. This happened in Norway because - according to the explanation - a screw was loose.44 An investigation by the German TÜV shows how trustworthy the safety standards are. The result: "A good one in five refuelling stations has significant defects".45 In accidents involving hydrogen cars, rescue operations are a challenge due to the pressurised container.
The emergency services cannot protect themselves against the pressure wave in tunnels. They ask themselves how "can people be rescued and fires fought effectively?"46 The simplest solution would be to ban these vehicles from travelling through tunnels, as well as from using underground car parks and ferries.
Windy "lighthouse projects"
Hydrogen should actually solve the storage problems caused by surplus energy from wind and sun. These do not always generate electricity when it is needed, but at other times they provide too much of a good thing. Then, according to the theory, hydrogen could be produced from water using high-temperature electrolysis instead of giving away surplus electricity to neighbouring countries.
Larger quantities can only be stored in underground caverns. The hydrogen is compressed for storage. When the gas is removed from storage, it has to be purified, as other gases, such as sulphur compounds and hydrocarbons, are released from the rock. The stored gas also absorbs water until it is saturated. This must also be completely removed before utilisation. Then there are microorganisms that obtain their energy from hydrogen. They are happy to have a table set for them, which favours rapid reproduction. Instead of odourless gas, there is then smelly bacterial slime. In addition, there are losses due to outgassing through cracks in the rock.39
The prospects for this type of energy storage are therefore bleak. Why else would Germany's "lighthouse project" among high-temperature electrolysis plants, called "Westküste 100", have been buried without a sound at the end of 2023?47 The existing offshore wind turbines would have repeatedly contributed surplus energy.
As "decarbonisation" with hydrogen from water will fail spectacularly, Europe's industry is responding to the coming energy slump by tapping into new natural gas fields in the North Sea.48,49 In order to produce the politically desired hydrogen, at least by steam reforming, a lot of natural gas is needed. Even the environmental scene is getting queasy: if H2 from "fossil natural gas" is to be an essential pillar for "ramping up the hydrogen economy", then something is going very wrong: this would not only be "devastating" for nature, but decarbonisation would generate even more carbon dioxide.50
Even Greenpeace has now realised that there is something fishy going on: "For water splitting, we use ... electricity from power plants that are fuelled with natural gas. And because of the efficiency losses in the power plant and electrolyser, we actually need around three times more natural gas than if the fossil fuel had gone directly into the gas turbine without being converted into hydrogen."51
At least technical progress is giving us a silver lining on the horizon. A new process, plasma pyrolysis, allows hydrogen to be produced much more economically for technical purposes, albeit from natural gas: methane is broken down using accelerated electrons. Around 3.3 kWh of hydrogen can be produced from methane using plasma pyrolysis from one kWh of electricity. Unfortunately, only 0.6 kWh of hydrogen can be produced from water with the same amount of energy. In addition, no carbon dioxide is produced, but coal (so-called "turquoise" hydrogen).52
New pranks
The next farce is already waiting to happen. There are not only microbes that digest hydrogen, but also those that produce it, so-called oxyhydrogen bacteria.53,54 The first company is already thinking about pumping bacteria and their nutrient solution underground, as in fracking, in order to extract the gas via another borehole.55
Genetic engineering could still give the bacilli a leg up. As they feed on sugars, amino acids and fatty acids, there is a new idea for the climate-conscious household: Hydrogen in reusable bottles made from fermented organic food with an eco-label. By the way: oxyhydrogen bacteria also live in the human gut ...
When the curtain falls
In order to "decarbonise" steelworks in the Ruhr region, Thyssen-Krupp was subsidised by the government to build a 4 km long hydrogen pipeline. Now the company is complaining about constant losses that are forcing it to cut back production. Its attempt to sell the steel division failed. It is complaining about a "lack of demand".56 Because energy has become extremely expensive in Germany and will rise to astronomical heights as a result of the hydrogen transition, economic production is impossible. Is it any wonder that energy-intensive industries are moving abroad?57
In Wiesbaden, the public transport company put 10 hydrogen buses into service. The joy of the successful eco-coup did not last long: "Expensive hydrogen adventure ends after just one year" wrote the press. First the vehicles ended up in storage and now they are to be sold on. A state capital "as it sings and laughs" has already struck. The new petrol station (costing around €2 million) is also moving with the buses, true to the slogan "Mainz fools stand together".
In Koblenz on the A 61 motorway, the only hydrogen filling station in Rhineland-Palatinate is closing down. Not profitable, despite subsidies. Another reason is the "ageing technology", which is from 2017. The material apparently has to pay tribute to the aggressive hydrogen and becomes brittle.58
Although the insurance industry insures local hydrogen plants, it is reluctant to get involved in large-scale networked projects to produce hydrogen from water. While the conventional method of producing hydrogen from methane only produces harmless carbon dioxide, the electrolysis of water releases oxygen instead. "A general process failure", warns Swiss Re, "that allows the hydrogen and oxygen streams to mix could lead to a much larger fire or explosion" than in a pure hydrogen catastrophe.59
Nuclear physicist Manfred Haferburg doesn't mince his words: "Green hydrogen", i.e. from water, "is an energy transition project whose governmental time and scope plans are characterised by megalomania, fantasies of omnipotence and physical-economic dilettantism. Not even the State Planning Commission of the GDR would have dared to go public with such nonsense."60
His colleague Hans Hofmann-Reinecke: "I have no doubts. This will be the final act in the drama known as the energy transition, a tragedy characterised by wilful blindness to economic realities, driven by ideology and dogmatism, devoid of logic and professionalism. And with this final curtain call, the success story of German industry comes to an end - "Not with a bang, but with a whimper."2
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