Understanding the Megajoule: A Measure of Energy in Natural Gas

The Megajoule (MJ) is a unit of energy widely used in the scientific, engineering, and energy sectors. It is a metric measurement representing one million joules. To grasp its significance, let's break down the term further:

Joule (J):

The joule is the fundamental unit of energy in the International System of Units (SI). It is named after the English physicist James Prescott Joule, who played a pivotal role in the study of thermodynamics. One joule is defined as the amount of energy transferred when one newton of force acts over a distance of one meter. In simpler terms, it quantifies the energy required to move an object with a force of one newton through a distance of one meter.

Megajoule (MJ):

The prefix "mega" denotes one million units. Therefore, a megajoule is equivalent to one million joules (1 MJ = 1,000,000 J). This unit is commonly used to describe larger amounts of energy, especially in contexts where a single joule may not be practical due to the vast energy quantities involved.

Natural Gas and Megajoules:

Now, let's link the concept of megajoules to natural gas. Natural gas is a fossil fuel primarily composed of methane, and it serves as a significant source of energy for various applications. When we discuss the energy content of natural gas, we often use the unit megajoule (MJ) to measure its energy potential. It allows us to quantify the amount of energy released when a specific volume of natural gas undergoes combustion or when it is utilized for heating, electricity generation, or industrial processes.

For instance, if a particular quantity of natural gas contains an energy content of 1000 megajoules (1000 MJ), it means that burning that volume of natural gas will release approximately one million joules of energy.

Comparing Megajoules

This informative infographic provides a relative comparison of various energy types, shedding light on their respective output, cost, and environmental impact in terms of CO2 emissions. Understanding the key differences between these energy sources is essential for making informed decisions about our energy future.


APGA Fact Sheets

In this series of fact sheets we unpack several key issues facing the pipeline and gas industry in the short to medium term. Each fact sheet focuses on a set topic and utlizes the most recently available industry research, and third party data to draw conclusions. 

APGA supports a net zero emission future for Australia by 2050. Renewable gases represent a real, technically viable approach to lowest-cost energy decarbonisation in Australia. As set out in Gas Vision 2050, APGA sees renewable gases such as hydrogen and biomethane playing a critical role in decarbonising gas use for both wholesale and retail customers. 

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Retail renewable gas forecast to cost customers less than retail renewable electricity

Renewable gas cheapest path to domestic decarbonisation

Please note that the information contained herin was correct at the time of publishing.

For more information please contact the APGA on apga@apga.org.au