Gas workers are preparing to mix gas with hydrogen: what does it mean to consumers and will our pipes cope with it?

Near Kharkiv, cabinet-type gas control points were tested for operation with a mixture of natural gas and hydrogen in a ratio of 80% to 20%. These are known to many "yellow cabinets" that reduce the pressure of gas before it enters homes or businesses.

This is a new technology, the goal of which is to replace some of the natural gas with "green" hydrogen, which, when burned, does not generate carbon emissions. It has both many advantages and many problematic points associated primarily with the cost of switching to it.

Kosatka.Media visited a testing ground and tells how new technology can change our lives, and what experts think about the feasibility of its implementation in Ukraine.

What happened at the test site

The peculiarity of hydrogen is the much smaller size of its molecule compared to natural gas. And if you fill the networks with pure hydrogen, it will disappear very quickly. But a mixture of 80% (gas)/20% (hydrogen) is considered optimal for gas networks, so it can potentially be used for heating houses and cooking.

The tests, which were arranged by the employees of JSC Kharkivgaz, must show whether the cabinet-type gas control points produced by RGC Production are suitable for working with a gas-hydrogen mixture. They are equipped with Pietro Fiorentini H2-ready regulators, which are certified to work with a 20% hydrogen mixture from the manufacturer.

Полигон Харьковгаза, на котором испытывали ШГРП

Kharkivgaz test site, where cabinet-type gas control points were tested. Photo: Kosatka.Media

The five most common types of hydraulic fracturing units have been tested with a capacity of 50 cubic meters or more per hour up to 350 cubic meters per hour, which are used to regulate gas for domestic and small industrial gas consumers.

Now such experiments are being carried out all over the world, and if the Ukrainian experiments are successful, this will not only reduce the "carbon footprint" in the environment (since hydrogen does not form carbon upon combustion), but also sell Ukrainian-made equipment abroad.

At the beginning of the tests, each of the cabinet-type gas control points is purged with an inert gas (nitrogen), after which a mixture of methane and hydrogen is fed.

A cylinder with a mixture of methane and hydrogen. Photo: Kosatka.Media

During a series of experiments, the gas service specialists checked the units and automation of the Cabinet-type gas control points. For example, how the safety shutoff valves work (should stop the gas flow if the pressure gets too high or too low), and whether gas is escaping through the connection.

The main purpose of the tests is to check whether the pressure-assisted hydraulic fracturing systems are holding pressure. To do this, the "cabinets" must stand under operating pressure for noon, and gas workers use gas detectors to periodically check for leaks.

“At the landfill, there are conventional cabinet-type gas control points, the same ones that we produce at our plants. Regulators that are certified to operate with a 20% hydrogen mixture are already on them from the start. That is, we did not modify them especially "for hydrogen". In a few days, the "cabinets" from the landfill will go to their customers," said Ihor Hotsyk, Deputy Head of the RGC hydrogen project.

This is not the first test cycle, before that, similar tests were carried out by Zhytomyrgaz. Later they will be held in Dnipropetrovsk, Volyn and Ivano-Frankivsk regions.

What should Ukraine "fill" its pipe with?

RGC says that they are testing only the technical aspect of the supply of a gas-hydrogen "cocktail". The economics of this process are not calculated. But just in time for the economic dimension of the transition to hydrogen, there are huge questions. At least for now.

First of all, where to get so much hydrogen? Ukraine consumed about 30 billion m3 of natural gas in 2020. Even replacing it with hydrogen by 20% means the need for 6 billion m3 of hydrogen. This is a huge volume.

As President of the All-Ukrainian Hydrogen Council, Oleksandr Repkin explained to Kosatka.Media, it is very difficult to say exactly how much hydrogen is produced in Ukraine now.

“Now these are private enterprises and it is very difficult to find their volumes. But one cannot even compare with the volumes that will be needed - they are ten times less," Repkin explained.

Besides, oddly enough, “not every hydrogen is equally useful”: in modern power engineering, as many as 6 types of hydrogen origin are distinguished - depending on the amount of carbon that enters the environment during its production.

Green hydrogen is produced by the electrolysis of water using electricity from renewable energy sources. This does not create a carbon footprint.
Gray hydrogen is hydrogen produced from methane with CO2 emissions.
Brown hydrogen is produced from CO2-emitted gasified coal. It is considered the least environmentally friendly.
Blue hydrogen is gray or brown hydrogen, but with carbon capture and storage (usually 50-70% efficiency).
Yellow hydrogen or pink hydrogen is electricity produced at a nuclear power plant is used.
Turquoise hydrogen is obtained by pyrolysis of methane with the formation of a by-product - solid carbon.

The very logic of decarbonization says that zero carbon emissions should be already at the stage of hydrogen production. This means that only green and yellow hydrogen can overcome the ecological barrier. At the same time, in 2019, about 96% of global hydrogen production was obtained from fossil fuels and only 4% from electrolysis. The same applies to hydrogen, which will be produced in Ukraine - now it acts as a technical gas and not a green energy carrier.

The second thing is how much green hydrogen will cost. According to the calculations of an expert in the field of energy Heorhii Havrylenko, the energy-consuming part of the cost of hydrogen produced from green electricity by electrolysis of water is UAH 15.2/m3 (excluding VAT). Whereas the lowest price at which natural gas is offered to the population is now 8.8 UAH / m3.

“This is only the energy-intensive part of the cost of hydrogen. The total cost includes the cost of chemical desalination of water, depreciation, transportation, operating costs (cost of reagents, salaries, spare parts, repairs, maintenance, etc.) And it will become at least twice as much, that is, it can reach UAH 30/m3," Havrylenko calculated.

Besides, it will be necessary to adapt gas networks for the use of a gas-hydrogen mixture (since hydrogen penetrates more easily through loose connections).

“We'll have to invest in infrastructure. If we consider hydrogen as a product of the future, then it is necessary to redesign and modernize the networks (replacement of joints, flanges, regulators, etc.), taking into account the hydrogen that can enter the network,” Ihor Hotsyk said.

Hydrogen may be interesting right now

At the same time, Kostiantyn Pyanykh, Deputy Director for Research at the Gas Institute of the National Academy of Sciences of Ukraine, reminds that the cost of green electricity is constantly decreasing. For example, in Saudi Arabia, a project has already been implemented to generate electricity at a solar power plant with a cost of 1 kW 1.3 cents. Under these conditions, the production of green hydrogen becomes economically attractive now.

“If we take the cost of a green kilowatt of 1.3 cents, then 4.5 kW of electricity is needed to produce 1 cubic meter of hydrogen, which costs 6 cents. To replace 1 cubic meter of natural gas, you need 3 cubic meters of hydrogen. Let it cost 20 cents or 6 hryvnia. And now household consumers buy gas at UAH 8/m3, and enterprises at UAH 15/m3. This is already interesting,” Pyanykh told to Kosatka.Media.

He added that Ukraine's gas networks already require replacement. If you do this correctly, then there will be no loss of hydrogen in the networks.

“It has already been worked out what the seals should be, what they should work with. And if everything is done correctly, then there will be no problems with natural gas, and with hydrogen. And even under the condition that hydrogen flows out, then in percentage, it will flow out more than natural gas, but since its calorific value is less than natural gas, it turns out that we will lose less in calories than we have lost would be in natural gas. Also, this gas mixture can be stored in our underground storages,” Pyanykh said.

All other pitfalls in the use of hydrogen, in his opinion, can be solved by legislative stimulation and regulation.

“If the country needs something, such a legislative field can be made to make it interesting. Now we are not talking about the fact that someone will pay less or more. Now we say - we are moving where the world is moving, or we sit and do nothing. Even Russia, which has natural gas, is ready to enter the hydrogen market if there is a demand for it. Why should we stay away from this?” Pyanykh summed up.