Calculation compensation for home charging at actual cost

In this article, we provide a detailed explanation of the calculation method we apply for the reimbursement of home charging costs for your company car, based on actual expenses incurred.

This only applies if your employer decides to reimburse your home charging sessions at actual cost.

Table of contents

1. Components of your electricity bill
2. Calculation of the actual cost of charging
   1. Electricity consumption
   2. Certificates for Green energy and Combined Heat and Power
   3. Grid costs
   4. Energy contribution
   5. Special excise duty
3. Calculation example per type of contract
   1. Fixed
   2. Variable
   3. Dynamic
4. Conditions for reimbursement at actual cost
5. Data processing and sources

Components of your electricity bill

Your electricity bill is made up of three key tariff components:

• Energy rates: This reflects the cost of the electricity you have consumed during the billing period
• Grid rates: These cover the costs associated with the construction, operation and maintenance of the electricity infrastructure, as well as the transmission of electricity
• Taxes and Levies: A range of government-imposed taxes and regulatory surcharges

Below, we provide a detailed explanation of the components specifically related to the purchase of electricity.

(1) In the context of variable energy contracts, suppliers may, during the term of the agreement, choose to amend the indexation parameter used in the pricing formula. This typically occurs when they determine that the existing parameter no longer accurately reflects prevailing economic conditions.

(2) In certain cases, energy suppliers also reserve the right to revise their tariffs if they believe the existing rates are no longer representative of current market realities. Where this is permitted, suppliers are generally obliged to provide customers with several months’ prior notice of any impending changes. Such provisions are usually detailed in the tariff sheets or within the supplier’s general terms and conditions

Calculation of the actual cost of home charging

When calculating the actual cost of charging your company car at home, only the costs directly attributable to charging sessions are taken into consideration. Specifically, we focus solely on the €/kWh component of your electricity bill.

Injection components are not taken into account. Nor do we include the fixed monthly and annual costs. These costs are charged anyway and are independent of the energy consumption for charging your company car.

The capacity rate is also not included in the calculation. Thanks to the MobilityPlus energy manager, the charging station will not generate a higher monthly peak than you have specified. Read more here

1. Electricity consumption

There are three types of electricity contracts in Belgium, each with distinct pricing structures:

a) Fixed contract

Under a fixed contract, the price per kWh remains unchanged throughout the duration of the agreement

b) Variable contract

In a variable contract, prices fluctuate monthly or quarterly, depending on the energy market. The price per kWh is calculated as follows:

Price (€/kWh)=((Factor (a)×Indexation parameter (X))+Term (b))/100

• Factor (a) (expressed in (1/10) x c€/kWh) and Term (b) (expressed in c€/kWh) are determined by the supplier
• Indexation parameter (X) (expressed in €/MWh), depends on the stock market and exchange prices (such as daily or forward prices) where your energy supplier buys the energy from

As a result, the final energy price may vary based on:

• The indexation period: monthly or quarterly
• The type of energy exchange: daily spot prices vs. forward prices
• The price listing method: average of several days or one single day (risk of high price)

Energy Suppliers determine which indexation parameter to use and may amend it mid-contract if market conditions shift significantly. Should such changes occur, they are required to notify customers in a timely manner. In our calculations, we always apply the indexation parameter that was in effect at the time of your subscription.

If any changes occur during your contract, it is essential to communicate this promptly. Send an email to energiecontract@mobilityplus.be with a copy of your energy contract and rate card attached.

c) Dynamic contract

Dynamic contracts are based on hourly market prices, specified by the BELPEX Day-Ahead Baseload prices. This implies that the electricity rate changes hourly, with prices published one day in advance, allowing consumers to align their usage with lower-cost periods (e.g. charging electric vehicles or running appliances).

The price per kWh is calculated using the following formula:

Price (€/kWh)=((Factor (a)×Hourly rate BELPEX)+Term (b))/100

• Factor (a) (expressed in (1/10) x c€/kWh) and Term (b) (expressed in c€/kWh) are determined by the supplier
• Belpex is the hourly market rate, expressed in €/MWh

2. Certificates for Green energy and Combined Heat and Power

In Belgium, energy suppliers are legally obliged to purchase a designated share of green energy. The costs associated with fulfilling this obligation are passed on to consumers in the form of Green Energy Certificates (GSCs) and, where applicable, Combined Heat and Power (CHP or WKK) certificates.

These certificates confirm that the energy has been produced within Europe from renewable sources. The charges are calculated based on your electricity consumption and are expressed in €/kWh. Consequently, the higher your consumption, the greater the cost.

Please note: CHP-related costs are currently only applied in Flanders, and do not apply in Wallonia or the Brussels-Capital Region.

The way in which these costs are calculated and applied varies between suppliers. For example, the frequency of rate updates and the calculation methods (in €/kWh) for GSCs and CHP certificates may differ.

Supplier-Specific Approaches:

• Eneco
  Eneco applies rates linked to the annual quotas for Green Eenergy Certificates and Combined Heat and Power (CHP) certificates.
  At the start of the contract, the rate is fixed in €/certificate. This rate remains valid for the duration of the contract (e.g. 1 year for a 1-year contract).
  Each year, this rate is indexed based on the certificate quota (number of certificates per kWh).
  The effective rate in c€/kWh for Green Energy Certificates and CHP can be calculated annually by multiplying the rate in €/certificate by the applicable, for the relevant part of the billing period.
• Mega
  For customers billed annually, the rates are updated quarterly. For customers with monthly billing, rates are updated monthly.
• Other suppliers
   We have not yet received comprehensive information from other suppliers regarding their practices. Until such data is made available, we will continue to update this component annually.
  If your energy supplier applies a different update frequency or calculation method, we kindly invite you to inform us. Send an email to energiecontract@mobilityplus.be with a copy of your energy contract and rate card attached.

3. Grid costs

In Belgium, grid costs represent a significant component of the electricity bill. These are levied by the distribution system operator (DSO) and are intended to cover the costs associated with maintaining, expanding and operating the electricity and gas networks. Grid tariffs are determined regionally and may vary annually or by DSO.

Overview of grid costs:

• Grid usage
  Charges for the use of the distribution network, including the transportation of energy to residential or commercial addresses. This fee covers infrastructure, operational and maintenance costs.
• Public service obligations
  These are levies imposed by the government to support societal objectives, such as energy efficiency programmes, the promotion of renewable energy, social tariffs, and the broader advancement of green energy initiatives.
• Surcharges
  These include costs associated with the transmission network operated by Elia, for long-distance energy transport and infrastructure investment.
  • Contributions to cover historical pension liabilities for employees within the energy sector.
  • Charges such as road usage fees and corporate income taxes, which are passed on to end users.
• Other transmission grid costs
  Additional levies may be applied in support of government objectives such as green energy certificates, renewable energy initiatives, or regional funding mechanisms.

These charges are typically passed on to consumers based on actual energy consumption, calculated in €/kWh.

4. Energy contribution

The federal energy contribution is a statutory charge, classified as a general excise duty. It is applied per kilowatt-hour (kWh) of natural gas and electricity consumed. The applicable rate per kWh differs between natural gas and electricity, but is the same for both residential and professional consumers.

Customers who qualify for the social tariff are exempt from paying this energy contribution.

5. Special excise duty

The special excise duty is a federal tax applied to each kilowatt-hour (kWh) of natural gas and electricity consumed.

This duty has been in effect since 1 January 2022. The applicable rates per kWh differ for natural gas and electricity and are determined by the consumer’s annual consumption volume. The consumption brackets are defined as follows:

• Consumption between 0 and 3,000 kWh
• Consumption between 3,000 and 20,000 kWh
• Consumption between 20,000 and 50,000 kWh
• Consumption between 50,000 and 1,000,000 kWh

In the calculation for the actual cost, we use the rate for the 3,000 - 20,000 kWh bracket. This is the bracket where the average consumer is located. The contribution for private consumers is different from professional consumers.

The special excise duty replaces the federal contribution, which you paid until the end of 2021. For electricity, the special excise duty also includes some costs that were part of transmission rates until the end of 2021 (such as certain surcharges and public service obligations).

Calculation example per type of contract

1. Fixed contract

Data:

• Customer type : Residential
• Region : Flanders
• Distribution grid operator : IMEWO
• Contracted meter type : day/night
• Contract type : fixed
• Energy supplier : Engie
• Energy consumption contract : Easy Fixed
• Subscription date : 01/04/2024
• Annual consumption : between 3,000 kWh and 20,000 kWh
• Rate sheet : See attachment ‘Rate sheet fixed contract’ (at the very bottom)
• Charging session at home : 31,25 kWh

Calculation:

For this charging session, € 7,97 will be reimbursed.

2. Variable contract

Data:

• Customer type : Residential
• Region : Flanders
• Distribution grid operator : IMEWO
• Contracted meter type : day
• Contract type : variable
• Energy supplier : Eneco
• Energy consumption contract : Zon en wind flex
• Subscription date : 01/04/2024
• Annual consumption : between 3,000 kWh and 20,000 kWh
• Rate sheet : See attachment ‘Rate sheet variable contract’ (at the very bottom)
• Charging session at home : 42,679 kWh

Calculation:

For this charging session, € 10,21 will be reimbursed.

3. Dynamic contract

Data:

• Customer type : Residential
• Region : Flanders
• Distribution grid operator : IMEWO
• Contracted meter type : day
• Contract type : dynamic
• Energy supplier : Luminus
• Energy consumption contract : Dynamic
• Subscription date : 01/04/2024
• Annual consumption : between 3,000 kWh and 20,000 kWh
• Rate sheet : See attachment ‘Rate sheet dynamic contract’ (at the very bottom) (source VREG)
• Charging session at home
  

  Start	End	Charged
  13/5/24 - 10u22	13/5/24 - 17u29	31,57 kWh

Calculation: see attachment ‘Calculation dynamic contract’ (at the very bottom)

For this charging session, € 4,01 will be reimbursed.

Conditions for reimbursement at actual cost

You have entered your current energy contract in the MobilityPlus app.
Read how to do this here

As long as no energy contract has been registered in the app, we are unable to reimburse your charging sessions. If you rectify this at a later stage, we will process a retroactive refund.

When you change your energy contract, you are responsible for updating the data in the app before the new contract takes effect. In fact, no retroactive corrections will be made. Read how to enter a new energy contract here.

Fixed energy contract

Once all relevant pricing information has been made available, you will receive a monthly overview of the registered charging sessions and their respective cost. This is done on the last working day of the following month.
E.g. For the charging costs of January '26, you will receive the overview on 27 February.

If MobilityPlus is responsible for paying your charging costs, your employer will receive an invoice for your charging costs on the same day. MobilityPlus will pay out your expense as soon as we have processed your employer's payment. Every 2 days we perform this check/payout.

Variable energy contract

• Monthly price change
  When all relevant pricing information is available to us, you will receive a monthly overview of the registered charging sessions and their respective cost. This is done on the last working day of the following month.
  E.g. For the charging costs of January '26, you will receive the overview on 27 February.

  If MobilityPlus is responsible for paying your charging costs, your employer will receive an invoice for your charging costs on the same day. MobilityPlus will pay out your expense as soon as we have processed your employer's payment. Every 2 days we perform this check/payout.
  
  

• Quarterly price change
  When all relevant pricing information is available to us, you will receive a quarterly overview of the registered charging sessions and their respective cost. This is done on the last working day of the month following the quarter in which the charging sessions took place.
  E.g. For the charging costs of quarter 1 2026 (Jan '26, Feb '26, Mar '26) you will receive the overview on 30 April.
  
  If MobilityPlus is responsible for paying your charging costs, your employer will receive an invoice for your charging costs on the same day. MobilityPlus will pay out your expense as soon as we have processed your employer's payment. Every 2 days we perform this check/payout.

Dynamic energy contract

When all relevant pricing information is available to us, you will receive a monthly overview of the registered charging sessions and their respective cost. This is done on the last working day of the following month.
E.g. For the charging costs of January '26, you will receive the overview on 27 February.

If MobilityPlus is responsible for paying your charging costs, your employer will receive an invoice for your charging costs on the same day. MobilityPlus will pay out your expense as soon as we have processed your employer's payment. Every 2 days we perform this check/payout.

Other contract types + charging station abroad

You will receive a monthly overview of the registered charging sessions and their respective cost. This is done on the last working day of the following month.
E.g. For the charging costs of January '26, you will receive the overview on 27 February.

If MobilityPlus is responsible for paying your charging costs, your employer will receive an invoice for your charging costs on the same day. MobilityPlus will pay out your expense as soon as we have processed your employer's payment. Every 2 days we perform this check/payout.

Data processing and sources

Energy rates

• Flanders
  Monthly, we collect current rates via the VREG cost simulator (VREG V-test), provided by the Flemish Regulator of the Electricity and Gas Market.
• Wallonia
  Rates are retrieved monthly via the CWaPE cost simulator (CompacWape), published by the Walloon Energy Commission.
• Brussels-Capital Region
  Each month, we collect tariffs through BRUGEL's Brusim cost simulator.

Grid rates

We gather the latest grid tariff data as published by the respective regional authorities:

For Flanders this is Fluvius, for Wallonia Cwape and for Brussels Sibelga

Indexation parameters variable rate

Indexation parameters used in the calculation of variable tariffs are collected monthly from available sources. While these parameters are applied across suppliers, only a few publish them. We collect data from Eneco, Engie, Dats24 and Luminus.

BELPEX Day Ahead Baseload
We collect daily BELPEX Day-Ahead Baseload prices as published by ENTSO-E. These are used to determine hourly dynamic pricing.

Levies and taxes

Each month, we obtain the current rates applicable to levies and taxes to ensure accurate calculation of reimbursement values.