Hydrogen Flashcards
(31 cards)
What is hydrogens melting and boiling points?
- Melting point: -259˚C
- Boiling point: -252˚C
What is needed to keep hydrogen liquid?
- High pressures or cryogenic temperatures
How does hydrogen usually exist?
Not naturally available alone, but abundant in compounds with other elements
What are some key characteristics of hydrogen?
Colourless, odourless, tasteless, non-toxic, and highly combustible
What are the colours of hydrogen?
Green
Blue
Grey
What is “green” hydrogen?
Produced from electrolysis and renewable electricity
What is “blue” hydrogen?
From fossil fuel but CO2 is captured and stored underground
What is “grey” hydrogen?
From fossil fuel and commonly uses steam methane reforming
(SMR) method
What was hydrogen used for in 1840s?
Fuel cells
What was hydrogen used for in 2010s?
Hydrogen-fueled combined cycle power plant
By what years did the Hydrogen Council predict medium/large hydrogen-powered cars would be fully accepted in the market?
2023 or 2025
In what industry is hydrogen used for heating purposes?
Steel industry
Besides heating and fuel for cars, what is another use of hydrogen mentioned by the Hydrogen Council?
Used for making fertilizers
As of the current time from the Hydrogen Council’s outlook, how many hydrogen production plans exist worldwide?
There are a lot of hydrogen production plans in the world
What is the expected capacity achievement for hydrogen production in the next 5 years according to the current status?
The expected capacity is 440,000 MW
What is the efficiency range of electrolysis in hydrogen production?
70% to 85%
What is a common method for producing hydrogen from methane?
steam-methane reforming reaction
What conditions are typically required for producing hydrogen from methane?
high temperature (700-1000°C) and/or high pressure.
In what two states can hydrogen be stored?
Liquid or gas
What is the pressure range for storing hydrogen gas in tanks?
Hydrogen gas is stored in high-pressure tanks ranging from 350 to 700 bar (5000-10,000 psi)
Why is hydrogen stored at cryogenic temperatures when in liquid form?
So it doesn’t boil back into gas
How can hydrogen be stored in solid materials?
Hydrogen can be stored on the surface of solid materials through adsorption or within solid materials through absorption
What is the efficiency range of fuel cells for energy extraction from hydrogen?
40% to 60%
What is the only residual output of hydrogen fuel cells?
water (H2O)
