Time-of-Use Tariffs Explained for Fleet Managers

Most fleet managers who have spent their careers operating diesel vehicles have never needed to understand electricity pricing in any detail. Diesel has a price; you pay it. Electricity has a price too, but it varies by hour, by day type, and sometimes by season, and the total invoice includes components that have no diesel equivalent at all.

When an operator transitions 20 or 30 vehicles to electric, suddenly the electricity contract becomes a significant operational cost driver rather than a background utility expense. This guide explains how time-of-use pricing works in the Netherlands, what the main contract components mean, and what fleet managers should look for when reviewing their tariff schedules.

What is a time-of-use tariff

A time-of-use (TOU) tariff is an electricity pricing structure where the cost per kWh varies depending on when you consume it. The underlying logic is straightforward: electricity is more expensive to produce and distribute at times of high demand (typically weekday mornings and evenings), so the grid operator or supplier passes that cost signal on to commercial consumers.

In the Netherlands, commercial electricity contracts are supplied by energy traders and suppliers operating under the regulatory framework of ACM (Autoriteit Consument en Markt). The underlying network transport tariffs are set by the regional network operators (Alliander, Enexis, Stedin, and Westland Infra being the main ones). Suppliers build their own pricing on top of those network costs, adding their margin and any additional services.

A typical commercial TOU contract for a logistics depot in the Netherlands distinguishes between peak hours (roughly 07:00 to 23:00 on weekdays), off-peak hours (23:00 to 07:00 on weekdays and all day on weekends), and sometimes a mid-peak band in between. The exact time windows and price differentials vary significantly by supplier and contract type.

Reading a Dutch commercial electricity bill

A standard Dutch commercial electricity invoice has several distinct line items that are worth understanding separately.

Energiekosten (energy cost): The cost of the actual kWh consumed, billed at the applicable tariff rate for each hour. On a TOU contract, this will show peak consumption billed at the higher rate and off-peak consumption at the lower rate. The difference between peak and off-peak energy rates on commercial contracts typically ranges from 30% to over 100% depending on the contract and market conditions.

Transporttarief (network transport tariff): The charge for using the network to deliver electricity from the generator to your meter. This is paid to the network operator (not the supplier) and is regulated by ACM. It includes a component based on the connection size (in kW of contracted capacity) and a usage component based on kWh consumed.

Capaciteitstarief or piekverbruikstarief (capacity or peak demand charge): This is the most important and often least understood component for fleet operators. The charge is calculated based on your peak power draw, typically measured as the highest 15-minute average kW reading during the billing period. The rate is set per kW per month.

Opslagduurzame energie (renewable energy surcharge, ODE): A national levy on energy consumption that funds renewable energy subsidies. Rates are set annually by the Dutch government.

BTW (VAT): 21% VAT on the total electricity cost for commercial consumers.

Why peak demand charges matter so much for depot charging

Fleet operators who are new to electric vehicles often focus their attention on the energy rate component of TOU tariffs. If I can shift charging to off-peak hours, I save on the kWh cost. That is true and the saving is real. But for depots where vehicles return in the late afternoon and early evening, the capacity charge is often a larger cost driver than the tariff arbitrage.

Here is why: the capacity charge is based on your highest 15-minute average draw in the month, not your average draw or your total consumption. If you have 30 vehicles plug in simultaneously when they return at 18:30, even for just one evening, that spike determines your demand charge for the entire billing period. One unmanaged evening can set your demand charge for 30 days.

Consider a depot with a contracted connection of 400 kW. If peak usage reaches 380 kW once in November, the demand charge for November is based on 380 kW regardless of what happens the rest of the month. At a capacity tariff of €9 per kW per month, that is €3,420 for November from that single spike. The same depot with managed charging that never exceeds 160 kW would pay €1,440 per month.

This asymmetry is important: demand charges reward consistent behavior, not average behavior. You cannot offset a bad evening in week one by being disciplined about charging in weeks two through four.

Seasonal and day-type variations in Dutch TOU tariffs

Some Dutch commercial contracts include seasonal pricing bands, where winter tariffs (typically November through March) are higher than summer tariffs, reflecting higher overall grid demand. The magnitude of this varies, but winter peak rates on some contracts can be 15% to 25% higher than summer peak rates.

Weekend pricing is more consistently favorable. Most Dutch commercial TOU contracts treat Saturday and Sunday as off-peak for the full 24 hours. For depots with weekend operations or where vehicles return on Friday afternoon and depart Monday morning, the weekend window represents a particularly good charging opportunity: an extended off-peak period without the constraint of an early Monday departure bearing down on a 7-hour overnight window.

Some contracts also distinguish between public holidays (treating them as weekend days) and normal weekdays. The exact holiday calendar that applies to your contract should be specified in the contract annexes.

Dynamic versus fixed TOU contracts

The Dutch electricity market has seen growing adoption of dynamic pricing contracts, where the per-kWh rate varies with real-time wholesale market prices (typically the APX/EPEX hourly day-ahead market). These contracts can offer lower costs during periods of high renewable generation (when prices occasionally go negative or very low), but they also expose the buyer to price spikes during supply crunches.

For fleet operators, dynamic contracts are more complex to optimize against because the price schedule is only known a day ahead (day-ahead prices are published around 13:00 for the following day). A charging scheduler that can consume day-ahead price data and plan overnight sessions accordingly can extract real value from dynamic contracts, shifting charging to the cheapest hours based on actual market prices rather than fixed time windows.

Fixed TOU contracts are simpler to plan against: the peak and off-peak windows are defined in the contract and do not change. For fleet operations teams without technical resources to set up live price feeds, fixed TOU is usually the more practical starting point.

What to check in your current contract

If you are currently operating diesel vehicles and about to add EVs, or if you have already added EVs and have not yet reviewed your electricity contract specifically for depot charging implications, there are three things worth checking immediately.

First, identify the exact peak and off-peak time windows in your contract. The answer may be in the contract itself or in an annex from the network operator. If your vehicles return during the peak window and your contract's peak rate is significantly higher than off-peak, you have a tariff arbitrage opportunity that a charging schedule can capture.

Second, find the capacity tariff component and understand the unit rate per kW per month. Multiply your estimated peak simultaneous charging load (charger count times charger power in kW) by that rate to get a worst-case demand charge estimate. Compare that to what you are paying now with diesel vehicles, which typically have much lower peak demand.

Third, check whether your current connection size (contracted capacity in kW or the fuse rating on your feed) is adequate for the charging load you are planning to add. Network operators publish their capacity tariff schedules, and upgrading a connection is a process that typically takes 6 to 18 months in the Netherlands, depending on the required grid reinforcement work in your area.

We are not saying every operator should rush to renegotiate their contract. In many cases, the existing contract is fine and the issue is purely one of charging behavior. But understanding the structure of what you are paying is the prerequisite for identifying where smart scheduling can actually move the needle for your specific situation.