SUDénergie: offers, prices and customer service in June 2026
SUDénergie (formerly SUDGAZ) is a long-standing energy player in Luxembourg, a specialist in natural gas and local biogas and, since 2023, a supplier of 100% green electricity. Owned by 14 southern municipalities, it is also the gas network operator for its area and supplies energy nationwide. Here’s the essentials: positioning, offers, contact, emergencies, and our verdict.
Compare SUDénergie with other suppliers
Energy prices change every month. Compare SUDénergie with competing offers available at your address, based on your real consumption.
Overview and positioning of SUDénergie
SUDénergie is a major local public player, owned by 14 southern municipalities of Luxembourg (Esch, Differdange, Pétange, Schifflange, Sanem, Käerjeng, Bettembourg, Kayl, Rumelange, Mondercange, Roeser, Reckange-sur-Mess, Dippach, Garnich). Historically a natural-gas specialist — and also the gas network operator in its area — it distributes gas and electricity nationwide.
SUDénergie’s strengths:
- ✓ Long gas expertise — over 125 years of experience, with competitive rates on the entry offer.
- ✓ A local biogas range — SUDgaz Green 50 and Green 100, to adopt green gas at your own pace.
- ✓ 100% green electricity — since 2023, notably from the SUDWAND wind farm (co-developed with Soler).
- ✓ Strong local roots — local, multilingual customer service and investment in local energy generation.
Good to know
SUDénergie’s electricity offer is recent and more limited than its gas range. Depending on your profile, other suppliers may offer more options (electric mobility, multi-year fixed price). To check the best choice, compare on our gas and electricity comparators.
SUDénergie offers in June 2026
SUDénergie offers three natural-gas plans (from conventional to 100% biogas) and a 100% green electricity offer. As prices change, find up-to-date rates and the comparison with other suppliers on our comparators.
Natural-gas offers
- ✓ SUDgaz Classic — conventional natural gas, at the most accessible rate.
- ✓ SUDgaz Green 50 — 50% biogas produced in Luxembourg, a good ecology/budget compromise.
- ✓ SUDgaz Green 100 — 100% Luxembourg biogas, the most eco-friendly offer.
→ Compare SUDénergie and competing gas offers
The electricity offer
- ✓ 100% green electricity — from renewable sources (wind, solar), introduced in 2023.
→ Compare SUDénergie and competing electricity offers
How to contact SUDénergie customer service?
For any commercial, contract or billing question:
- ✓ By phone — on +352 55 66 55 1 (Mon–Fri, 8am–12pm and 1:30pm–5pm).
- ✓ By email — [email protected].
- ✓ Online — via the contact form.
Head office: 150, rue Jean-Pierre Michels, L-4243 Esch-sur-Alzette (postal address: B.P. 383, L-4004 Esch-sur-Alzette).
Gas emergency, outage or problem: what to do?
SUDénergie is the gas network operator in its 14 municipalities: for a gas smell or leak in that area, it is the one to call in an emergency. For electricity, the network is not operated by SUDénergie: a power cut is reported to Creos.
🔥 Gas smell or leak (SUDénergie area) — leave the premises, do not operate any switch, then call SUDénergie’s gas emergency on +352 55 66 55 66 (24/7). Outside the SUDénergie area, call Creos’s gas emergency on 8007-3001.
⚡ Power cut — the network is run by Creos: call 8002-9900 (24/7).
📄 Billing or contract issue — contact SUDénergie customer service (see above).
Good to know: switching supplier never causes an outage. Supply is guaranteed by the network operator, whatever your supplier.
The history of SUDénergie: from gasworks to green electricity
The story began in 1899 with a gasworks built in Esch-sur-Alzette by the Carl Francke company (Bremen), intended for public lighting. In the 20th century, the company modernised and expanded: acquisition by several municipalities, conversion to natural gas in 1972, then transformation into SUDGAZ S.A. in 1989.
The 21st century marks the energy-transition turning point: first renewable projects, renaming to SUDénergie in 2021, launch of a green electricity offer in 2023, and inauguration of the SUDWAND wind farm (a joint venture with Soler) to provide the cleanest possible energy to its customers.
Frequently asked questions — SUDénergie
Is SUDénergie a reliable supplier?
Yes. SUDénergie is one of Luxembourg’s main energy suppliers, with over 125 years of experience. A public company owned by 14 southern municipalities, it is also the gas network operator for its area, making it a particularly solid, locally rooted player.
What energies does SUDénergie offer?
Two: natural gas (three plans — Classic, Green 50, Green 100) and 100% green electricity, introduced in 2023. The company also develops its own renewable installations (wind, solar).
What is the difference between SUDénergie’s gas offers?
SUDgaz Classic is conventional natural gas at the best price. Green 50 contains 50% Luxembourg biogas (ecology/budget compromise). Green 100 is 100% local biogas, the most eco-friendly offer. Compare on our gas comparator.
What should I do in case of a gas smell or emergency?
In the SUDénergie area (14 southern municipalities), immediately call the gas emergency on +352 55 66 55 66 (24/7). Outside the area, the Creos gas emergency is on 8007-3001. Meanwhile, open the windows, do not operate any switch, and leave the premises if the smell is strong.
What is biogas and what are its benefits?
Biogas is a renewable alternative to natural gas, produced locally by anaerobic digestion of organic matter. It cuts the carbon footprint and supports Luxembourg’s energy independence, with the same technical characteristics as conventional gas (no change to your installation needed).
How do I become a SUDénergie customer?
You can subscribe online, by phone on +352 55 66 55 1, or at the head office in Esch-sur-Alzette. Switching supplier is free and causes no interruption. Compare offers first to check the best choice: gas · electricity.