A hidrogén energiahordozó, amit először elő kell állítani, hogy aztán a fogyasztók kinyerhessék és felhasználhassák a benne tárolt energiát. Általánosságban véve ez kétféleképpen tehető meg: elektrolízissel, valamint fosszilis üzemanyagokból. Amennyiben az ehhez felhasznált villamos energia megújuló energiaforrásokból (pl. napelemek, szélerőművek) származik, a folyamat fenntartható energiatermelési módot biztosít. Ezért nevezik zöld hidrogénnek.
WHAT IS HYDROGEN?
Hydrogen is an explosive and pure combustion gas. Because hydrogen weighs less than air, it rises in the atmosphere, so it is rare in pure form (H2).
In the flame of pure hydrogen gas burning in air, hydrogen (H2) reacts with oxygen (O2) to form water (H2O) and release energy.
The energy released allows hydrogen to act as a fuel. This energy can be used with relatively high efficiency.
Hydrogen can be produced by the cleavage of water with electricity (electrolysis) or by the cleavage of fossil fuels or biomass with heat or steam, “reforming” or “pyrolysis”. CO2 can be captured and stored.
Hydrogen can be stored, liquefied and transported via pipelines, trucks or ships. Hydrogen can be used to produce fertilizer, as a vehicle fuel, to heat homes, to generate electricity, or to drive heavy industry.
Hydrogen is generally considered an energy carrier as electricity because it must be produced from a primary energy source.
In the hydrogen economy, hydrogen would be used instead of fossil fuels, which currently account for four-fifths of the world’s energy supply and account for much of global greenhouse gas emissions. This could help climate goals, as it only emits water when hydrogen is burned and can be produced without CO2 emissions.
What is blue hydrogen?
Blue hydrogen is when natural gas is decomposed into hydrogen and CO2 by steam-methane reforming (SMR) or automatic thermal reforming (ATR), but the CO2 is sequestered and then stored. As greenhouse gases are captured, this mitigates the environmental impact on the planet. Simply put, hydrogen is considered blue if emissions from the steam process are isolated and stored underground through industrial carbon capture and storage (CSS).
What is gray hydrogen?
Gray hydrogen is produced from fossil fuels and currently accounts for about 95 percent of global production. The oldest way to produce hydrogen is to convert coal to gas. This gasification process converts fossil-based materials to carbon dioxide, carbon monoxide and hydrogen. Gasification takes place at an incredibly high temperature, without combustion, with the addition of a controlled amount of oxygen and / or steam. The carbon monoxide then reacts with water to form carbon dioxide and additional hydrogen through a water-gas transfer reaction.
Coal-fired gas produced by coal gasification and hydrogen can be separated from the other elements by means of absorbers. This is the result of a highly polluting process as both CO2 and carbon monoxide cannot be recycled and are released into the atmosphere.
What other hydrogen is there?
Hydrogen from biomass.
It can also be produced from hydrogen biomass by gasification. Depending on the type of biomass, but depending on the use of carbon capture and storage technologies, net CO2 emissions may be lower using these technologies.
Hydrogen obtained from nuclear electrolysis is pink.
What is green hydrogen?
Instead of fossil fuels, green hydrogen is produced from electricity produced from renewable energy sources such as solar energy, biomass, electricity (eg in the form of solar photovoltaics or wind turbines). It currently accounts for 1% of total hydrogen production.
Green hydrogen can provide clean energy for manufacturing, transportation and many other areas – and its only by-product is water. Green hydrogen produces zero carbon emissions. Essentially, this hydrogen is the gold standard for the clean energy sector.
Why is green hydrogen a big deal?
Green hydrogen is one of many potential low-carbon fuels that could take the place of today’s fossil hydrocarbons. True, hydrogen as a fuel is far from ideal. Due to its low density, it is difficult to store and transport. And its flammability can be a problem.
However, the arguments in favor of hydrogen are clear; the world needs a zero-emission fuel that is well known, has extensive regulations and standards, is easily scalable, and can be used in a variety of energy sectors. Hydrogen is the fuel. Only in the next decade, according to research by the Fuel Cells and Hydrogen Joint Undertaking, hydrogen could reduce CO2 emissions by 1.7-6.3 million tonnes by 2030, supporting the further deployment of 1800 MW-9 GW of wind power and 830 MW-4 GW of solar energy. .
Hydrogen is already widely used in industry, so the technical problems of storage and transportation are not insurmountable. The potential for widespread use of green hydrogen means that many companies are looking for opportunities to exploit and utilize the hydrogen fuel economy. The most significant of these are oil and gas companies (which are increasingly facing calls to reduce fossil fuel production). The interest of large oil companies in green hydrogen can be crucial in achieving fuel commercial viability. Reducing the cost of producing green hydrogen requires huge investments and huge sizes, which large oil companies can provide in a unique way.
Are we late for that too? Where is Hungary?
Given that on 8 July 2020, the European Union presented a roadmap for the promotion of green hydrogen, which is “one of the key priorities of the European Green Agreement and of Europe’s transition to clean energy”. It is seen as a technology that can bridge the gap between renewable electricity generation and the goal of a high-carbon decarbonization of the EU’s energy supply.
Similar policy developments are taking place in Australia, Canada, Japan, the Netherlands, Germany, France, Portugal and the United States – ministers are under great pressure to prepare Hungary in time to become a competitive exporter in this sector.
What about hydrogen-powered vehicles?
In addition to oil and gas companies, renewable energy developers also see green hydrogen as an emerging market, and last month offshore wind market leader Ørsted announced the first major project targeting the transport sector exclusively in Denmark. The eye-catching Toyota Mirai helped fuel early hopes that hydrogen fuel cell vehicles could compete with electric cars to replace internal combustion engines. But as the electric vehicle market boomed, the prospects for hydrogen to become a serious competitor faded, at least in the passenger car segment. There are currently roughly 18,000 hydrogen fuel cell cars and 31,000 forklifts on the world market, compared to more than 373,600 electric outlet cars by December 2020.