Back to list

Gas : 11 key words and phrases about energy transition you need to know

Biomethane, biogas, cogeneration, NLG, Power-to-Gas: these are words we hear a lot when gas is mentioned in the context of energy transition. Do you know exactly what they mean?


Biogas : unlike natural gas, biogas or “green gas” does not come from underground sources; it is produced by the transformation of organic matter (wood, plants, organic domestic, agricultural and industrial waste, sewage sludge) by the action of microorganisms in an oxygen-free envi (anaerobic digestion). It is a renewable gas principally composed of methane, an energetic gas that is used to produce electricity and heat or as vehicle fuel. Illustration : Gabriel Quintana, via


Biométhane : this is biogas that is purified in such a way that it has the same properties as natural gas and can be injected into the natural gas transport and distribution network. It can also be used for heating, producing hot water and as vehicle fuel, as bio-NGV. Illustration : KOIVO, via

Centrales à Cycle Combiné Gaz Turbine (CCGT)

Combined Cycle Gas Turbine (CCGT) plants (CCGT) : CCGT power plants are developing very strongly and are increasingly contributing to the energy mix. They combine They combine a gas turbine and a steam turbine to produce electricity: heat resulting from the combustion of the gas is used to the maximum to increase energy efficiency. Illustration : Danny Ivan, via


Cogeneration : cogeneration involves the combined production of electricity and heat from a single source of primary energy, such as natural gas. Generally, electricity generation releases a large amount of waste heat. Cogeneration reuses this heat, and the energy efficiency of such an installation can reach and even exceed 85%. Illustration : Hyo Kim, via

GNL (Gaz Naturel Liquéfié)

LNG (Liquefied Natural Gas) : LNG is simply natural gas that has been transformed into liquid form thanks to cooling at a temperature of approximately -161° C at atmospheric pressure so it can be more easily stored and transported around the world in LNG tankers. It is also used as a fuel for vehicles as well as for river and sea transport. Illustration : Florent Bodart, via

GNV (Gaz Naturel pour Véhicules)

NGV (Natural Gas for Vehicles) : NGV is simply natural gas used as a fuel for vehicles, whether in compressed form (CNG: Compressed Natural Gas) or liquefied form (LNG: Liquefied Natural Gas). It is an alternative fuel offering both ecological and economic benefits. It reduces CO2 emissions by 25% in comparison to gasoline, and it reduces emissions of nitrogen oxide particulates by 80% in comparison with light-duty diesel vehicles. It can be used by passenger cars as well as by heavy trucks, buses and garbage trucks. NGV is even less polluting in its low-carbon or carbon-free and renewable versions: Eco-NGV (incorporating 30% biomethane), Bio-NGV (100% biomethane) and Bio-LNG. Illustration : Roland Banrevi, via


Hydrogen : hydrogen is a light gas found very abundantly on Earth. In oxidation with oxygen it produces electricity. It is a means of storing energy, particularly useful for renewable energies when not all the energy produced can be used. It can also be used to produce energy, particularly when used in fuel cells, to power hybrid vehicles and autonomous energy production systems. Illustration : Hyo Kim, via

Loi sur la Transition Energétique

Energy Transition Law : French legislation coming into effect in August 2015 on energy transition for green growth, also known as the “energy transition law”, sets the key targets for a new French energy model in both global and European contexts: aims include reducing the country’s greenhouse gas emissions by 40% between 1990 and 2030 and ensuring that 10% of gas consumed is from a renewable source by 2030. Illustration : Leonardo Dentico, via

Mobilité verte

Green mobility : this notion covers the use of alternative fuels to petroleum, particularly LNG and CNG and their carbon-free and low-carbon versions, as well as electricity, with the aim of reducing CO2 emissions in cities and in long-distance freight transportation.
Illustration : Vanessa Gonzales, via

« Power to Gas »

Power-to-Gas (aka P2G) : these technologies consist in converting surplus electricity produced by wind turbines and solar panels into hydrogen or synthetic methane (methane syngas). This produces renewable gas with numerous possible applications in industry and transport. The gas can also be injected into the gas distribution network. Illustration : Robert Farkas, via

Back to list