Glossary

Excise duties due on electricity; on shared kWh, they appear on the invoice issued by the sharing representative.

Also known as: excise duty, excise

Solar generation combined with a farming activity: roofs of farm buildings, shade structures over pasture, raised arrays over crops. In Wallonia only roofs are exempt from planning permission; ground-mounted arrays remain a derogation in agricultural zoning and still await their implementing order.

Also known as: agrisolar, agricultural solar

Automatic Meter Reading: a remotely read meter recording quarter-hourly values, usually fitted on higher-capacity connections. CWaPE accepts it on the same footing as a communicating meter for taking part in energy sharing.

Also known as: AMR meter, automatic meter reading

Non-profit association (Belgian 'ASBL'), a common legal form for shared-energy projects.

Also known as: non-profit association

Legal person automatically grouping all the co-owners of a building, responsible for preserving and administering it. Its assets are limited to the movable property needed for that purpose (art. 3.86, § 3, of the Civil Code), so it cannot own the photovoltaic installation that feeds an energy sharing operation.

Also known as: ACP, co-owners' association

An assessment carried out by an approved auditor who produces a report and a prioritised list of works. In Wallonia it is a precondition for almost every Habitation grant — only roof interventions are exempt — and the entitlements it opens remain valid for eight years.

Also known as: energy audit

Consuming your own electricity generation instead of feeding it into the grid. It is the most profitable use of an installation, since a self-consumed kWh avoids buying one at the full retail price.

Also known as: self consumption

Self-consumption carried out by several parties, within one building or a defined perimeter. It falls under a regulatory framework distinct from individual self-consumption and requires an allocation key between participants.

Prior approval from the regulator, required when a community steps outside the standard framework — in particular for an allocation key that does not belong to the families recognised in its region.

Also known as: authorization

The category of participants to which the Walloon decree reserves effective control of an energy community, alongside natural persons and SMEs. The list of eligible entities was annulled by the Council of State on 28 March 2025 — leaving only the municipality, the sole entity named by the electricity decree — then restored and widened by the decree of 5 February 2026, in force since 26 February 2026. The restored list covers municipalities, provinces, public social welfare centres, inter-municipal companies and every school, whatever its network.

Also known as: local authorities

A fixed charging point for an electric vehicle, wired into the dwelling's installation. Controllable models modulate their power continuously to follow solar generation; in single phase, modulation stops below 6 amps, roughly 1.4 kW.

Also known as: wallbox, charging point

The Brussels regulator for the electricity and gas markets. It defines the allocation methods permitted in the Brussels-Capital Region and supervises the energy communities operating there.

Generic abbreviation for energy community, covering the different legal statuses that exist — REC, CEC or LEC, depending on the originating European directive and the Belgian region concerned.

Also known as: energy community

Citizen energy community, as defined by the European internal electricity market directive. Technology-neutral but limited to electricity, it imposes no geographic proximity requirement on its members.

Also known as: citizen energy community

Local energy community, a status specific to the Brussels framework. It allows electricity sharing between participants inside a local perimeter set by regional rules, under BRUGEL's supervision.

Also known as: local energy community

Renewable energy community, as defined by the European RED II directive. It covers renewable energy only, and its members must be located in proximity to the generation assets the community owns.

Also known as: renewable energy community, REC

Support mechanism for renewable electricity; on shared energy, the obligation to surrender quotas (PSO) is passed on to the sharing representative's invoice.

Also known as: green certificates, green-certificate quota

A domestic hot-water tank fitted with a heat pump, with a coefficient of performance between 2.5 and 3.5. For the same hot-water need it consumes about three times less electricity than a resistive tank — and therefore absorbs about three times less solar surplus.

Also known as: heat pump water heater, thermodynamic water heater

An electricity supply chain reduced to the minimum of commercial intermediaries between a local producer and its consumers. Unlike the food short supply chain, defined by the Walloon administration as allowing at most one intermediary, it never removes the network operator, whose charges remain payable: it shortens the energy component of the bill, not the physical path of the current.

Also known as: short supply chain for electricity, short circuit

The rule determining how shared energy is split between participants, applied quarter-hour by quarter-hour to actual meter readings. Each Belgian region recognises its own families of standard keys.

Also known as: repartition key, distribution key

A household that, because of its social situation, benefits from the social tariff and from specific protections. Federal protected customers — recipients of certain forms of public welfare assistance, of certain Federal Pension Service allowances or of disability-related allowances — generally obtain it automatically through data matching. Regional protected customers must request a certificate and pass it to their grid operator. Increased-reimbursement status alone has not conferred this entitlement since 1 July 2023.

Also known as: protected customers

Unique 18-digit identifier of a supply point, starting with 54 in Belgium; it changes neither when the meter is replaced nor when the supplier changes.

Also known as: EAN, EAN number

The ratio between the heat an appliance produces and the electricity it draws to produce it. A coefficient of 3 means three kilowatt-hours of heat for one kilowatt-hour drawn. The higher it is, the less the appliance consumes — and the less solar surplus it can absorb.

Also known as: COP

A Walloon municipal body convened, at the request of the network operator or the customer, before a supply suspension. It brings together the social welfare council, the network operator, the CPAS social energy guidance service and the customer, and rules by majority on guaranteed minimum supply, debt relief, heating oil vouchers or meter reopening. An appeal lies to the justice of the peace.

Also known as: Local Energy Commissions

An entity that brings members together to produce, consume, store or share energy.

Also known as: energy community

The mechanism known as the meter running backwards: injections are annually netted off withdrawals. Banned under European law beyond 31 December 2023, it remains secured in Wallonia until 31 December 2030 for systems commissioned before 1 January 2024 — and must be given up to take part in energy sharing.

Also known as: net metering, meter running backwards

The share of the bill corresponding to the price per kWh set by the supplier, around 40 % of the total; the only competitive component, and the only one energy sharing acts on.

Also known as: pure energy component

A meter able to record and transmit consumption in quarter-hourly steps. It is the technical precondition for energy sharing: without data at that granularity, no allocation key can be applied.

Also known as: communicating meter

A meter that measures electricity drawn from the grid and electricity injected separately. Mandatory in Wallonia for any solar installation commissioned from 1 January 2024, it makes compensation impossible and is the precondition for selling the surplus at the injection tariff.

Also known as: bidirectional meter, two-way meter

A second meter, with its own EAN code, feeding only a dedicated circuit — hot-water tank or storage heating — during a night-time window, most often 22:00 to 07:00 or 21:00 to 06:00 depending on the substation. Since 1 January 2026 ORES has aligned its distribution rate with dual-rate off-peak hours: it therefore no longer offers any advantage to a dual-rate customer, and it heats water at night, when no panel is producing.

Also known as: exclusive night meter, night-only meter

A consumer-unit device that closes the circuit of a large load — typically the hot-water tank — when the meter switches to off-peak, and cuts it when peak hours return. Now that Walloon off-peak hours cover 11:00 to 17:00, it heats water partly during solar production; you still have to check it has not been left in a forced position.

Also known as: off-peak contactor, water heater contactor

The contract under which a supplier pays for the electricity a producer feeds into the grid. It is separate from the supply contract and its price is regulated nowhere in Belgium. Without compensation, it is the only way to monetise a surplus other than through sharing or self-consumption.

Also known as: export contract, feed-in contract

Contract between the participants in an energy-sharing scheme setting out their rights and obligations, including the allocation key and the price of the shared electricity.

Also known as: energy sharing agreement

A voluntary European initiative through which a municipality commits to cutting its greenhouse gas emissions by at least 55 % by 2030 and to submitting an action plan within two years of its decision to join. 230 Walloon cities and municipalities out of 262 had signed by mid-September 2024.

A structure with variable capital and democratic governance, often chosen to host an energy community. The "one person, one vote" principle answers the European requirement of effective control by members.

Also known as: co-op

Situation of a building divided into at least two units held by different owners and containing at least one common part. In Brussels, that definition matches almost word for word the definition of the building that opens the right to share energy.

Also known as: co-ownership, condominium building

A representation of the power drawn by a supply point over time, in Belgium at quarter-hourly resolution. It is the curve, not the annual volume, that decides what a participant can actually absorb in a sharing operation: two profiles consuming the same amount over the year but not at the same hours are worth entirely different things to the group.

Also known as: load profile, consumption curve

Levelised cost of production: the methodology that has set, since 1 June 2024, the green certificate grant rate for new Walloon installations, in every technology except photovoltaics below 10 kW. The rate is fixed by ministerial order and revised annually against market prices, so it must be checked on the day of the application.

Also known as: levelised cost of production, CPMA regime

The Walloon energy regulator. It defines the families of standard allocation keys, receives the notification of energy communities, and authorises non-standard keys.

Also known as: Walloon Energy Commission

Settlement invoice based on the meter readings; it calculates real consumption over the period and settles the instalments already paid.

Also known as: settlement invoice, annual settlement

Real right allowing someone to own constructions on another's land, for up to 99 years since Book 3 of the Civil Code. It is the structure through which a cooperative or a third-party investor becomes owner of panels installed on a common roof; granting it requires four fifths of the votes at the general meeting.

Also known as: superficies

Water heated for domestic uses — showering, dishes, washbasin — as opposed to water in the heating circuit. When produced electrically, it is the most attractive load to shift onto solar production: its consumption is daily, fully shiftable in time and independent of whether anyone is home. The tank must nonetheless reach 60 °C regularly to prevent legionella.

Also known as: DHW, hot water

A deliberate reduction of the power injected by a generating installation, imposed by the grid operator when the local grid is constrained, or chosen at the design stage. Curtailed energy simply does not exist: it can be neither injected nor shared, and no sharing agreement recovers it.

Also known as: clipping, output curtailment

Energy produced and consumed within a nearby area, without passing through the transmission grid. Proximity is a legal criterion for renewable energy communities, not merely an intention.

Energy from renewable sources such as solar, wind or hydropower.

Also known as: green energy

The share of your consumption that sharing does not cover and that your supplier keeps billing at your contract price. It always exists, because sharing only applies during the quarter-hours when local production is available.

Also known as: complementary energy

The process of calculating and issuing the amounts due for energy and related charges.

Also known as: invoicing

Periodic advance calculated from an estimate of annual consumption, usually the previous year's; it does not reflect actual consumption.

Also known as: instalment, advance invoice

Invoice issued when moving home or switching supplier, drawn up from the final meter reading to close the supply point.

Also known as: final invoice

Document in which a supplier publishes the prices and parameters of a product; it is the binding reference for checking the amounts shown on an invoice.

Also known as: tariff sheets, price sheet

The ability to adjust generation, consumption or storage according to the grid's needs.

The distribution system operator for the whole of Flanders. It supplies the quarter-hourly metering data and applies the allocation keys recognised by the Flemish regulator VREG.

A federal fund contributing, through the CPAS, to the purchase of heating gasoil, bulk propane or kerosene by modest-income households. In 2026 the allowance runs from €0.14 to €0.20 per litre, within a limit of 1,500 litres and €300 per year, or a €210 flat rate for purchases at the pump. It is the only scheme covering heating fuels that have no social tariff.

Also known as: Heating Fund

The company that sells energy to the final customer and bills their residual consumption. In an energy-sharing setup, its invoice coexists with the one issued by the sharing representative.

Also known as: energy supplier

An electronic certificate attesting that one megawatt-hour of renewable electricity was produced somewhere in the European Economic Area. It is sold independently of the electricity, stays valid for twelve months and travels between countries: it proves production, not delivery.

Also known as: guarantees of origin

How decision-making and the community's internal rules are organised.

Distribution system operator: the company responsible for the low- and medium-voltage grid up to the meter. It collects the quarter-hourly data and applies the allocation key.

Also known as: distribution system operator, DSO

Presenting a product or service as more environmentally friendly than it is. The FPS Economy targets a claim that is false, presented in a misleading way or that cannot be verified, prohibited by articles VI.93 to VI.100 of the Code of Economic Law.

Also known as: green washing

Transmission system operator: the company responsible for the high-voltage grid that carries electricity to the distribution networks. In Belgium this role is held by Elia.

Also known as: transmission system operator, TSO

A network of 16 offices and 40 consultants run by the Walloon public service, providing personalised, neutral and entirely free technical advice on household energy: grants, tariffs, insulation, heating, photovoltaics. First contact through the 1718 freephone number.

Also known as: Walloon Energy Desks

Energy sent back to the grid when local generation exceeds instantaneous consumption. It is paid at the injection tariff, generally far below the retail price of electricity.

Also known as: grid injection

A cycle of recalculating the allocation or sharing within an algorithm.

A Walloon subsidy for modest-income households covering energy-saving works in the main dwelling: window frames, insulation, a stove, chimney lining, a boiler or a water heater. It reaches €2,000 since 13 June 2022 and can be doubled depending on the type of works. It is filed exclusively through the CPAS, with a minimum of five years between two applications.

Also known as: MEBAR grant

Body of appeal in a dispute with a supplier or a network operator, after a prior written step; the federal service handles the contract and the price, the regional services the meter and the network.

Also known as: energy ombudsman, SRME

A person or entity that joins an energy community and takes part in its governance. The European directives reserve effective control to natural persons, local authorities and small enterprises.

Also known as: participant

The composition of the electricity that no guarantee of origin claims, once every holder has withdrawn theirs. It is the mix assigned by default to a customer without a green offer: 18.07 % renewable in Belgium in 2024, against 49.38 % in the Walloon supply mix.

Also known as: Belgian residual mix

Prior declaration filed with the regulator before a sharing operation starts. In Wallonia, CWaPE acknowledges receipt, and that acknowledgement conditions the actual launch of sharing with the grid operator.

The device that converts the direct current produced by solar panels into usable alternating current. Its rating in kWe is the net deliverable capacity used to compute the Walloon prosumer tariff; it is usually replaced around year twelve.

Also known as: solar inverter

Electricity sharing between two supply points only, for instance between two neighbours, without creating a legal entity. Operational in Brussels and Flanders; provided for by the Walloon decree since 2022 but still inoperative for lack of an implementing order.

Also known as: P2P sharing

Splitting locally generated electricity between the participants of a community or a single building. It is an administrative and tariff operation: the electrons keep flowing across the grid exactly as before.

The operation by which energy is distributed among the participants of a given sharing scheme.

A person or entity whose supply point is included in a sharing operation. Being a participant does not necessarily mean being a member of the legal structure behind the community.

Also known as: member

A constituted legal entity, mandatory to host an energy community: the European directives require it explicitly. In practice, the non-profit association and the cooperative are the commonest forms in Belgium.

Also known as: legal person

The technology that converts solar radiation directly into electricity. It supplies most of the energy shared in Belgium, with a fleet of 12.8 GWp at the end of 2025 generating more than 10 TWh.

Also known as: solar panels, solar panel, solar photovoltaic

The document adopted by a municipality that has signed the Covenant of Mayors, to be submitted within two years of the council's decision to join. It rests on an emissions inventory and structures actions around three families: energy efficiency and sufficiency, renewable energy generation, and shifts between energy carriers.

Also known as: SECAP, climate action plan

The contractual delivery point for energy, identified by a unique EAN code. It is the base unit of a sharing operation: the allocation key applies per supply point, not per person.

Politique locale Énergie Climat: the Walloon programme that has supported municipalities committed to the Covenant of Mayors since 2012. Coordinated by APERe with the Walloon Air and Climate Agency and the Union of Walloon Cities and Municipalities, it funds an energy-climate coordinator and part of the external support. The carbon neutrality decree provides for its move from annual calls for projects to a drawing right, optional and to be activated by the Government.

The legal person — municipality, province, Wallonie-Bruxelles Enseignement, a denominational or non-denominational non-profit — that organises a school and acts as its legal counterpart. For energy sharing its identity matters little: the decree of 17 March 2023 ranks all schools among local authorities, whatever their network, in order not to create discrimination between school networks.

Also known as: organising authorities

The situation of a household that faces particular difficulty, in its home, in meeting its basic energy needs. The Royal Decree of 19 April 2024 sets three official indicators, computed on Statbel's SILC survey: measured poverty (an excessive share of income spent on energy), hidden poverty (abnormally low consumption, a sign of self-restriction) and perceived poverty (self-declared difficulty keeping the home warm).

Also known as: fuel poverty

Walloon regional support for home renovation, conditional on a prior housing audit. The temporary support scheme runs until 30 September 2026; a new scheme built around the Rénopack and Rénoprêt is due to take over on 1 October 2026.

Also known as: Habitation grants

Price per kWh at which shared electricity is transferred between members of an energy community; it covers the energy component only, excluding network fees and taxes.

Also known as: internal price, shared energy price

The energy a solar installation produces in a year per unit of installed capacity, expressed in kWh/kWp. In Wallonia the accepted order of magnitude is 950 to 1,000 kWh/kWp a year for an unshaded, due-south roof at 35°.

Also known as: annual yield, kWh/kWp

A user who both consumes and produces electricity at the same supply point, typically a household with solar panels. In Wallonia this status triggers the prosumer tariff and determines the regime applying to the injected surplus.

Also known as: prosumers

The maximum electrical capacity an installation can inject into the grid, in practice that of the inverter expressed in kWe. It is the basis for computing the flat prosumer tariff in Wallonia — not the peak capacity of the panels expressed in kWp.

Also known as: net developable power

A 15-minute measurement interval used to calculate energy sharing.

Also known as: quarter-hourly, 15-minute interval

A connection granted to a generating installation on condition that the grid operator may limit its injection during the hours when the local grid is constrained. It allows a faster and cheaper connection on a saturated grid, at the price of curtailment whose extent must be quantified before sizing the installation.

Also known as: flexible access, dynamic limitation

The ability of an electric vehicle to return energy from its battery to the home (V2H) or to the grid (V2G). In Belgium in 2026 the offering remains marginal: bidirectional charge points at €4,000-8,000, few compatible models and an unsettled connection standards framework.

Also known as: V2G, V2H, vehicle-to-grid, vehicle-to-home

Flat annual amount charged by the supplier regardless of the kWh consumed; it must be pro-rated to the actual duration of supply.

Also known as: fixed fee, standing fee

Person or entity designated in the agreement to organise the sharing and invoice the shared energy to participants, based on the grid operator's data.

Also known as: energy sharing representative

A device that continuously measures the electricity about to leave for the grid and redirects it to a resistive load, most often the hot-water tank, watt by watt. At €400 to €900 installed, it is the cheapest way to absorb a solar surplus.

Also known as: power diverter, surplus diverter

The electricity and gas distribution operator for the nineteen Brussels municipalities. It reads the meters and applies the allocation methods approved by BRUGEL.

The rule that governs energy sharing: only electricity produced, injected into the local network and consumed within the same quarter hour is allocated. It forbids any carry-over from one slot to the next — whatever is not absorbed within the quarter hour leaves the sharing arrangement and falls back to injection.

Also known as: simultaneity rule, concurrency

Temporarily holding energy, most often in a battery, to release it later. It raises the self-consumption rate by shifting consumption towards the hours when generation happens.

Also known as: battery

Electricity that is generated but not consumed on site, which can be injected into the grid or sold.

Also known as: production surplus

The portion of surplus generation actually sent to the grid after local consumption and sharing. Reducing it is the direct aim of a good allocation key, since it earns far less than a consumed kWh.

Agent who carries out the decisions of the general meeting and runs the building day to day. The mandate may not exceed three years and, unless the meeting expressly decides otherwise, no commitment may be entered into beyond that term — a decisive point for an open-ended sharing agreement.

Also known as: property manager, syndic

The power a home draws continuously, even when empty: fridge, freezer, ventilation, router, standby. In the order of 200 to 300 W in a Belgian house, it is the only guaranteed self-consumption of a household away during the day — around 1.5 kWh over the 11:00 to 17:00 window, where a 4 kWp system produces more than ten on a June day.

Also known as: baseload, standing consumption

A grid tariff formula distinguishing two time bands, whose split differs from one region to another. In Wallonia since 2026 the bands are identical every day, weekends included: off-peak from 11:00 to 17:00 and from 22:00 to 07:00. In Brussels the historic split still applies: off-peak from 22:00 to 07:00, plus weekends and public holidays. In Flanders the distribution tariff no longer distinguishes day from night since the 2023 capacity tariff. Do not confuse the Walloon bands with the Impact tariff bands, which differ.

Also known as: dual-rate, off-peak hours, peak hours

The Flemish distribution tariff in force since January 2023, calculated on monthly peak power rather than on the hour of consumption. The average peak recorded by the VREG is around 3.15 kW, with a billed minimum of 2.5 kW. It removes the day/night distinction from the grid part of the bill: the useful move is no longer to consume at night, but to avoid running everything at once.

Also known as: capacity term

Price per kWh paid by a supplier for electricity injected into the grid; unregulated in Belgium, it acts as the floor for the internal transfer price.

Also known as: buyback tariff, feed-in tariff

A contribution to network costs owed by owners of a photovoltaic installation in Wallonia, calculated on net deliverable capacity — €80.98/kWe excluding VAT on the ORES 2026 schedule, i.e. €85.84/kWe including VAT. It applies as a flat charge only to meters that do not record actual gross withdrawals.

Also known as: prosumer charge

The share of the bill covering use of the transmission and distribution grids. These costs remain payable on shared electricity: sharing acts on the energy component, not on the network component.

Also known as: network tariff

A maximum price for electricity, gas or heat, reserved for protected customers. It is set by the CREG every quarter, published in the Belgian Official Gazette and identical across every supplier: switching operator changes nothing. It covers the energy and grid components, but not the special excise duty or the connection charge.

Also known as: social energy tariff

A contract whose electricity price follows hourly wholesale market prices: advantageous for anyone who genuinely shifts consumption, riskier otherwise. Requires a smart meter.

Also known as: dynamic tariff, dynamic contract

The Walloon network tariff structure available from 2026, which varies the proportional term across time bands (ECO, MEDIUM, PIC) to discourage consumption peaks. Optional, reversible, restricted to smart meters — marketed by ORES as the Impact tariff.

Also known as: Impact tariff

Share of local generation consumed on site rather than fed into the grid. Expressed as a percentage, it is the indicator that measures the economic performance of an installation or an allocation key.

The share of generated energy actually distributed between participants rather than fed into the grid. Together with the self-consumption rate, it is the indicator used to compare two allocation keys.

Tax levies applied to the energy bill according to the local framework.

Also known as: levies

The part of the network tariff calculated on the power drawn rather than on the kWh consumed. In Flanders it is based on the highest quarter-hour peak of the month, with a 2.5 kW floor; in Brussels it is tied to connection capacity.

Also known as: capacity tariff, power term

An operator that finances, installs and maintains a photovoltaic installation on someone else's roof, is remunerated on the electricity produced, then transfers the panels at the end of the contract — often about ten years. As long as it owns the output, the operator and not the occupier has the surplus at its disposal: without an express clause, the installation cannot feed any energy-sharing operation.

Also known as: third-party investment, third party investor

An adviser employed by a Walloon CPAS and subsidised by the Region since a Walloon Government decision of 28 August 2008. They visit the household, read the bills with it, spot costly usage and activate the support it is entitled to without knowing. Funding largely runs through the preventive energy action plans (PAPE).

Also known as: energy tutors

Value-added tax: 6% for a residential customer, 21% for a professional customer; due on the shared energy invoiced by the sharing representative.

Also known as: value-added tax, value added tax

Allocated value: the share of generation assigned to a participant, expressed either as an absolute value or as a percentage depending on the allocation key.

Also known as: allocated value

Allocated value as a percentage: the allocated share of generation expressed as a percentage of the allocation key.

Also known as: allocated value percentage

The Flemish energy-market regulator, renamed 'Vlaamse Nutsregulator' on 1 January 2025.

Also known as: Vlaamse Nutsregulator