getty
Hydrogen often comes up in conversations about clean energy, and a range of colors is sometimes used to describe a completely colorless clean-burning chemical that can be used as a substitute for coal, oil or gas in a wide variety of applications. But for its use to have net environmental benefits, hydrogen must be produced from clean sources, rather than from fossil fuels, which is the current standard method.
So-called “brown hydrogen” is usually obtained from coal and has been produced to supply cities with light since the early 19th century: through water and heat, the coal undergoes gasification, and in that process, the chemicals in the coal react to produce what is known as town gas, now known as synthesis gas, which contains a mixture of carbon dioxide, carbon monoxide, hydrogen, methane and ethylene, along with small amounts of other gases. The first two are of no value for power generation, making the process highly polluting compared to other methods, although chemical companies can distill hydrogen from this mixture relatively easily. In addition, waste-to-energy incinerators often use similar processes to generate brown hydrogen from biomass and petrochemicals. The vast majority of synthetic gas still comes from coal.
So-called “grey hydrogen” makes up the vast majority of the hydrogen produced today, and is obtained from natural gas. Generally, when hydrogen comes up in conversations, the interests of an oil company are behind it. Its production generates large amounts of carbon dioxide, and although it is the cheapest process, its price is being driven up by taxes on carbon dioxide generation, and will logically be more costly in the future.
Blue hydrogen is also produced from hydrocarbons, but by incorporating carbon dioxide capture and storage (CCS) technologies into the process, which eliminate the emissions from the production of grey hydrogen and reduce its environmental impact. Production has has been slow, but as CCS-related projects grow to avoid taxes on carbon dioxide generation, its price is beginning to decline.
Green hydrogen does not come from any type of fossil fuel, and instead from the hydrolysis of water by means of electricity obtained from renewable sources. According to energy market analysts, green hydrogen made from wind and solar electricity could become the cheapest form of a much faster-than-expected transformative fuel. Several Chinese manufacturers have succeeded in making electrolysis systems to create hydrogen from renewable energy at costs up to 80% lower than estimates from just two years ago. At those prices, hydrogen would become the best way to store energy from the sun or wind for use when the sun is not shining or the wind is not blowing, as well as for a growing range of industrial uses.
Taxes on carbon dioxide emissions are the best means to trigger the transition to clean energy: a carbon price of $50/tCO2 would be sufficient to make the switch from coal to clean hydrogen in steelmaking by 2050 attractive. If we get to $60/tCO2, hydrogen is the best way to make cement, at $78/tCO2 it can be used to make chemicals like ammonia, and at $145/tCO2 it makes economic sense to power ships with clean fuel. If hydrogen costs drop to $1/kg then running heavy trucks will also be cheaper with hydrogen than with diesel by 2031, although batteries will still be the logical and cheaper solution for cars, buses and light trucks.
The European Union has a strategic plan for the transition to green hydrogen, with a view to decarbonization and climate neutrality in the future. Hydrogen, therefore, is fundamental for the future of energy and decarbonization, but not all hydrogen is valid in this transition: we need to accelerate the transition to green hydrogen obtained from clean sources. The oil industry is deliberately trying to sow confusion over whether hydrogen could replace electric vehicles: green hydrogen will most likely be used as energy storage and in a growing range of industrial processes in the future, instead of for refueling our vehicles. But from now on, when we hear about hydrogen, let’s clarify what we’re talking about, what we mean, and what color it is. Even if it’s still colorless.
"use" - Google News
October 05, 2020 at 05:01PM
https://ift.tt/36wtCyP
What Does “Green” Hydrogen Mean, And What Can We Use It For? - Forbes
"use" - Google News
https://ift.tt/2P05tHQ
https://ift.tt/2YCP29R
Bagikan Berita Ini
0 Response to "What Does “Green” Hydrogen Mean, And What Can We Use It For? - Forbes"
Post a Comment