Green electricity in Belgium: really green?
In 2024, suppliers active in Wallonia declared a supply mix that was 49.38 % renewable. That same year, the Belgian residual mix — what is left once every guarantee of...
News
The latest news from the OptimCE project
Two reference articles to start with: the Belgian framework in “Energy communities in Belgium: CER, CEC, CEL” and the sharing calculation in “Allocation key in Belgium: the 3 regions”. The sector's vocabulary is collected in our glossary.
Solar surplus: the 5 options compared
A 4 kWp installation generates around 3,800 kWh a year, and nearly 2,400 of them leave the house with nobody to use them. Five options exist to do something about...
Energy community: CWaPE documents and deadlines
The CWaPE has ten working days to declare your notification complete, and a dossier left incomplete for six months lapses altogether. The annual report, for its part, falls every year...
Solar panels 2026: still worth it in Wallonia?
Wallonia added only about 100 MWp of solar in 2025, when 500 to 600 a year would be needed to stay on its 2030 trajectory. The doubt is therefore measurable,...
Energy poverty in Wallonia: available support
Wallonia has the highest energy poverty rate in Belgium: 29.2% of households, against 16.4% in Flanders. Support exists — social tariff, MEBAR, Social Heating Fund, energy tutor — but it...
Cheaper electricity without switching supplier
Every guide to saving on electricity ends with the same sentence: compare, then switch supplier. Yet one mechanism lowers the bill without cancelling anything — energy sharing. The question is...
Which electricity tariff to choose in Belgium?
Social tariff, night rate, dynamic contract: three answers to the same question, and they do not act on the same part of your bill. This costed comparison separates them using...
Read your Belgian electricity bill line by line
You receive a dozen documents a year called an invoice, and only one of them actually tells you what you owe. Since 2022, a royal decree has imposed five identical...
Reduce your electricity bill: Wallonia 2026
The official comparator, the new Impact tariff, the social tariff, the 30 September grant deadline, self-consumption and energy sharing: ten Walloon levers costed from the ORES 2026 tariff schedule approved...
Why your electricity bill stays high in Belgium
Energy prices have collapsed since 2022 and excise duties drop on 1 August 2026. Yet your bill barely moves. A euro-by-euro breakdown of the four blocks — energy, network costs,...
Invoicing shared electricity in Belgium
In energy sharing, two invoices coexist: your supplier's and the sharing representative's. Who issues what, which VAT rate applies (6 or 21%), how to handle excise duties and green certificates,...
Internal transfer price in an energy community
What price per kWh should apply to the electricity shared between members? What the internal price really covers, the defensible range between injection tariff and energy component, five calculation methods,...
Billing in an energy community
New OptimCE feature: automatically generate your energy community's invoices, from the price per kWh to the PDF and payment tracking.
Engaging energy community members
An energy community is first and foremost a social project. Here's how to inform, engage and involve your members in decisions — with a news board, polls and participatory governance...
Simulate an allocation key: test your scenarios
New OptimCE feature: simulate an allocation key on your own data and measure self-consumption, surplus, self-sufficiency and the sharing rate.
Energy self-consumption in Belgium
Understanding self-consumption in Belgium: definition, the self-consumption rate and how to raise it, collective self-consumption and its link with energy communities, the differences between Wallonia, Brussels and Flanders, who benefits,...
Reduce your electricity bill: energy communities
Joining an energy community lets you pay less for electricity at a more stable price. We explain the savings levers, a worked example, the differences between Wallonia, Brussels and Flanders,...
Automatic allocation key generation
OptimCE's automatic generation module is now live. It proposes optimised allocation keys from a community's real production and consumption data, with two algorithms — brute force on standard keys and...
Allocation key in Belgium: the 3 regions
Allocation key in an energy community — types accepted by CWaPE, BRUGEL and VREG, regional differences across Wallonia, Brussels and Flanders, and practical guidance to choose one.
Join an energy community in Wallonia
How to join an energy community in Wallonia: eligibility, where to find an open sharing operation (OptimCE registry, SPW facilitator, Énergie commune), steps to enrol and points to check before...
Create an energy community in Wallonia
How to set up an energy community (CER or CEC) in Wallonia: choosing the model, legal structure, CWaPE notification, acknowledgement of receipt, and launching the energy sharing with ORES, RESA...
Energy communities in Belgium: CER, CEC, CEL
Understand energy communities in Belgium — differences between renewable, citizen and local energy communities, how energy sharing works, key actors and benefits.
May 2026 release: public registry and guide
A new OptimCE release is out, with bug fixes, a brand-new user guide and a public registry to discover open energy-sharing operations.
Install OptimCE: quick start guide
Two ways to get started with OptimCE: the hosted version, with nothing to install, or a local deployment of the full stack with Docker Compose. Prerequisites, cloning with submodules, environment...
Energy communities in Europe: RED II and IEMD
Two European directives govern energy communities: RED II for renewable energy communities, the internal electricity market directive for citizen energy communities. What separates them, what they share, and how Belgium,...
Launching OptimCE: the origins of the project
OptimCE was not born in an incubator but in a laboratory. A look back at Locomotrice, the Walloon research project that produced the platform, at the partners behind it, and...