The switch from "lean" to "rich" gas in Brussels: a successful 3-year conversion

Remember? In 2020 and 2021, no fewer than 11 of Brussels’ municipalities (i.e. nearly325,000 households ) were converted to rich gas. On the basis of a timetable agreed at federal level, the Brussels-Capital Region had been divided into 3 zones, successively converted in 2020, 2021 and 2022.

Towards the third and final conversion wave

On the 1st of September, 2002, the remaining municipalities, namely Forest, Uccle, Ixelles, Etterbeek, Auderghem, Watermael-Boitsfort, Woluwe-Saint-Pierre and Woluwe-Saint-Lambert, successfully switched to rich gas. 

Why this change? 

Until 2020, the Brussels-Capital Region was exclusively supplied with lean gas from the north of the Netherlands. However, due to dwindling gas reserves, the Dutch government has decided to gradually reduce exports of lean gas from 2024 until exports cease completely by 2030. It was therefore essential for Belgium and Brussels to quickly turn to alternative sources of supply such as rich gas, which comes from other regions such as Norway, Algeria, the United Kingdom and Qatar. 

“Although this conversion is not a result of the war in Ukraine, it nevertheless makes it possible to diversify sources and contribute to the security of natural gas supply for more than 500,000 Brussels customers” 

Inne Mertens, Managing director, Sibelga

No impact on your energy bill

The conversion of the distribution network by Sibelga will have no impact on your energy bill or your gas consumption. The difference between these two gases lies in their calorific value: for the same volume of gas used, rich gas generates more heat than lean gas. The supply of rich gas will therefore have no impact on the bill, as the amount of the bill is calculated on the basis of the number of kilowatt-hours consumed and not on the volume of gas delivered.

98% of the appliances in Brussels ready for the conversion

98% of the appliances in Brussels are ready for conversion to rich gas with or without pre and/or post conversion adjustment. In fact, the appliances sold in Belgium since 1978 are adapted to both types of gas (lean and rich). 
Appliances installed before 1978 or purchased abroad are not compatible with rich gas and will have to be replaced.

Tip: performed at the same time as the mandatory 2-yearly periodic inspection of the boiler and water heaters, the compatibility check by an authorised technician should not generate any additional costs for the user. 

Finally, it is important to note that an appliance that is not compatible with rich gas or that is incorrectly adjusted will not work optimally. It could therefore consume more gas, deteriorate faster or present safety problems (produce more carbon monoxide).

Subsidies granted by Brussels Environment and

A regional subsidy is available to help disadvantaged households carry out the mandatory periodic inspection. Find out more on the Brussels Environment website.
To replace a boiler purchased before 2000, it is also possible to apply for a subsidy on the website


For address-by-address conversion details, a list of approved technicians or the appliances affected, visit or call free of charge on 0800/11 744.