Energy Content of Hydrogen: A Comparison

Hydrogen, often considered the fuel of the future, is garnering significant attention due to its vast potential as an energy carrier and its environmentally friendly nature. It can be produced using different technologies, including electrolysis, which involves splitting water into hydrogen and oxygen using electricity. Electrolysis is a clean and sustainable method, especially when the electricity used comes from renewable sources like solar, wind, or hydro power. However, it’s essential to understand the energy requirements of various electrolyzer technologies to make informed decisions about their efficiency and potential applications.

Energy Equivalency of Fuels Calculator

Our Fuel Conversion Tool allows you to effortlessly convert between quantities of various fuels, such as hydrogen, methane, methanol, petrol/gasoline, diesel fuel, crude oil, LPG, natural gas, and ammonia, based on their energy content. All you have to do is select the input fuel, input value, input unit, output fuel, and output unit. Then, simply hit the “Convert” button to see the equivalent amount of output fuel. This tool uses the lower heating values (LHV) of fuels for the conversions.

Fuel Conversion Tool






Equivalent amount of output fuel:

Sources: Energy Equivalency of Fuels, Useful Conversions and Thermodynamic Properties

The following table was used to create the calculator:

FuelUnitEnergy Content (LHV, MJ)Energy Content (HHV, MJ)Conversion Factor
Hydrogen (H2)1 kg120142
Hydrogen (H2)1 N-m312.7
Hydrogen (H2)1 pound64.4
Methane (CH4)1 kg5055
Methane (CH4) / Natural Gas1 million cubic feet8538 kg H2
Methanol (CH3OH)1 kg19.9
Petrol/Gasoline1 kg4446
Petrol/Gasoline1 gallon121.31.008 kg H2
Diesel fuel1 kg4246
Crude oil1 kg4247
Crude oil1 barrel47.30 kg H2
Liquefied petroleum gas (LPG)1 kg4651
Natural gas1 kg4255
Ammonia1 kg18.822.5
Energy content and conversion factors for conventional and alternative fuels

This table includes the energy content in MJ for some specific units and the conversion factors between hydrogen and other fuels.

Understanding Hydrogen’s Energy Content

Hydrogen can exist in different states: gaseous, liquid, and solid. The energy content of hydrogen depends on the state it is in, and each state has its advantages and disadvantages.

Gaseous Hydrogen

Gaseous hydrogen has a lower volumetric energy density compared to other fuels, which means it takes up more space for the same amount of energy. However, its gravimetric energy density (energy per unit of mass) is higher. Gaseous hydrogen has a lower heating value (LHV) of about 120 MJ/kg and a higher heating value (HHV) of about 142 MJ/kg.

Liquid Hydrogen

Liquid hydrogen has a higher volumetric energy density compared to gaseous hydrogen, making it more suitable for transportation and storage. Its LHV is similar to gaseous hydrogen, but it requires cryogenic storage (-253°C) to remain in a liquid state, which can be energy-intensive and expensive [1].

Solid Hydrogen

Solid hydrogen has the highest volumetric energy density of all three states. However, it requires extremely low temperatures (-260°C) and high pressures to exist, making it impractical for most applications [2].

Comparing Hydrogen’s Energy Content with Other Alternative Fuels

Now that we’ve discussed hydrogen’s energy content in its various states, let’s compare it with other alternative fuels.

Natural Gas

Natural gas, primarily composed of methane, has an LHV of about 50-55 MJ/kg [3]. This means that hydrogen has more than double the energy content per unit mass. However, natural gas has a higher volumetric energy density, making it easier to store and transport. Natural gas can also be used to produce hydrogen through methane reforming.

Ethanol

Ethanol, a biofuel derived from plants, has an LHV of about 27 MJ/kg [4]. Hydrogen has more than four times the energy content per unit mass. However, ethanol has a higher volumetric energy density and can be stored and transported more easily.

Biodiesel

Biodiesel, another biofuel produced from vegetable oils or animal fats, has an LHV of about 37 MJ/kg [5]. Hydrogen has more than three times the energy content per unit mass. Like ethanol, biodiesel has a higher volumetric energy density, which makes it easier to store and transport.

Electric Batteries

Electric batteries store energy in the form of electrochemical energy. While they don’t have an LHV, their energy density can be compared in terms of watt-hours per kilogram (Wh/kg). Lithium-ion batteries, commonly used in electric vehicles, have an energy density of about 150-250 Wh/kg [6]. To put this in perspective, hydrogen’s energy content of 120-142 MJ/kg is equivalent to about 33,333-39,444 Wh/kg.

Hydrogen Carriers: Expanding Hydrogen’s Potential

While hydrogen has a high gravimetric energy density, its low volumetric energy density poses challenges for storage and transportation. One solution to this problem is using hydrogen carriers, which are substances that can store and release hydrogen.

Metal Hydrides

Metal hydrides are compounds formed when hydrogen is absorbed by metals. They can store hydrogen at relatively low pressures and moderate temperatures, making them safer and more efficient than gaseous hydrogen. However, the overall energy density is lower due to the added mass of the metal.

Chemical Hydrides

Chemical hydrides, such as ammonia borane and sodium borohydride, can store hydrogen through chemical bonds. These compounds can release hydrogen when heated or combined with a catalyst. While they have a higher hydrogen storage capacity than metal hydrides, they often require higher temperatures for hydrogen release and may produce byproducts that need to be managed.

Liquid Organic Hydrogen Carriers (LOHC)

LOHCs are organic compounds that can reversibly store hydrogen in their molecular structure. Some examples include toluene and dibenzyltoluene. LOHCs can store hydrogen at near-ambient conditions and release it upon heating or through a catalytic process. They have a lower hydrogen storage capacity compared to metal or chemical hydrides, but their liquid nature makes them more compatible with existing infrastructure for storage and transportation.

Hydrogen Production Energy Calculator

Our Hydrogen Production Energy Calculator considers three types of electrolyzers: Alkaline, PEM (Proton Exchange Membrane), and Solid Oxide. Each electrolyzer type has its own specific energy consumption range, which influences the overall efficiency of hydrogen production. By using our calculator, you can easily input the desired mass of hydrogen (in grams, kilograms, or tonnes) and select the appropriate electrolyzer type to calculate the energy required for production. You can even choose your preferred energy output unit, such as MJ, GJ, kWh, or MWh, for a convenient and straightforward experience.

Source: Heat Values of Various Fuels

Hydrogen Production Energy Calculator

Hydrogen Production Energy Calculator

Frequently Asked Questions

What is the energy content of hydrogen per m3?

The energy content of hydrogen per cubic meter (m3) depends on its state. For gaseous hydrogen at 25 °C and 1 bar, the volumetric energy density is approximately 12.7 MJ/m3. Methane has a volumetric energy density of 40 MJ/m3 at the same temperature and pressure [7].

How much energy is in 1 liter of hydrogen?

The energy content of 1 liter of hydrogen also depends on its state. For gaseous hydrogen at 25 °C and 1 bar, the energy content is approximately 12.7 kJ/L.

How many kWh can 1 kg of hydrogen produce?

1 kg of hydrogen has a heating value of about 120-142 MJ/kg. Converting this to kilowatt-hours (kWh), 1 kg of hydrogen can produce approximately 33.3-39.4 kWh of energy.

What is the energy content of hydrogen by volume?

The energy content of hydrogen by volume depends on its state and conditions (temperature and pressure). For gaseous hydrogen at 25 °C and 1 bar, the energy content is approximately 12.7 MJ/m3 or 12.7 kJ/L.

How do you calculate the energy of hydrogen?

To calculate the energy of hydrogen, multiply its mass by its lower heating value (LHV). For example, if you have 2 kg of hydrogen with an LHV of 120 MJ/kg, the energy content would be 2 kg * 120 MJ/kg = 240 MJ.

How do you find the total energy of hydrogen?

To find the total energy of hydrogen, you need to know its mass and LHV. Multiply the mass by the LHV to get the total energy. For example, if you have 5 kg of hydrogen with an LHV of 142 MJ/kg, the total energy would be 5 kg * 142 MJ/kg = 710 MJ.

How many MW is 1 ton of hydrogen?

1 ton of hydrogen is equal to 1,000 kg. With a heating value of 120-142 MJ/kg, 1 ton of hydrogen can produce 120,000-142,000 MJ. Converting this to megawatts (MW), assuming a continuous energy output for one hour, 1 ton of hydrogen can produce approximately 33.3-39.4 MW.

How many m3 is 1 kg of hydrogen?

At STP, 1 kg of gaseous hydrogen has a volume of approximately 11.1 m3.

How much energy does 1g of hydrogen produce?

1 gram of hydrogen has a heating value of about 120-142 kJ/g. Therefore, 1g of hydrogen can produce 120-142 kJ of energy.

How many liters is 1 kg of hydrogen?

At STP, 1 kg of gaseous hydrogen has a volume of approximately 11,100 liters.

What is the cost of 1 kg hydrogen?

The cost of 1 kg of hydrogen depends on factors such as production method, location, and purity. As of 2021, the cost of 1 kg of hydrogen ranged from $2 to $16, with an average of around $6. However, prices are subject to change and may vary in the future.