The Bill That Catches Everyone Off Guard
You plugged in your EV, put the oven on, and ran the dishwasher — all at the same time. Fifteen minutes later, your entire month's network bill changed. That's Belgium's capacity tariff, or capaciteitstarief, and it's one of the most misunderstood charges on Belgian electricity bills.
The good news: once you understand how it works, it's highly avoidable. And with the right setup, you can keep it at the absolute minimum every single month.
What Is the Capacity Tariff?
Since 2023, Fluvius has calculated your monthly distribution network cost based not on how much electricity you use, but on how much you draw at once — specifically, your single highest 15-minute average power peak of the month.
The formula is simple but the consequences are not:
Monthly network cost = your highest 15-minute peak (in kVA) × the Fluvius rate per kVA
The minimum is capped at 2.5 kVA. So even if you live very efficiently, you'll pay for at least 2.5 kVA every month — roughly €25–30 on your distribution bill depending on your grid operator.
But if your peak goes higher — which it easily does with an EV charger — the cost jumps proportionally.
The Real Numbers: What It Actually Costs
Monthly Peak | Typical Cause | Approx. Monthly Network Cost |
2.5 kVA (minimum) | Basic household, no EV | €25 – €30 |
4 kVA | Occasional EV charging + cooking | €40 – €48 |
7 kVA | Unmanaged 11kW EV charger + appliances | €70 – €84 |
11 kVA | EV + heat pump + oven simultaneously | €110 – €132 |
The difference between a managed and unmanaged household is often €50–100 per month — €600–1,200 per year — purely from how that peak is shaped, not from how much electricity you actually use.
What Triggers a High Peak?
The most common culprits are:
EV charging at full speed. An 11 kW EV charger running while the oven (3 kW) and heat pump (6–9 kW) are active. That's 20+ kW in one 15-minute window.
Heat pump startup. Heat pumps draw significant power on cold mornings, especially when defrosting. Combined with morning showers, cooking, and appliances, this is a classic spike.
Electric boiler. Older boilers drawing 6–9 kW. If you haven't switched yet, this is a hidden peak contributor.
Laundry + dishwasher simultaneously. If your dishwasher runs at the same time as the washing machine and dryer, the combined load easily reaches 5–7 kW.
The key insight: it only takes one 15-minute window. One bad morning can define your entire month's bill.
5 Ways to Avoid a High Capacity Tariff
1. Never charge your EV at full speed during peak hours
Set your EV charger to a maximum of 6 kW during the hours when other appliances are running. Most chargers — Easee, Wallbox, go-e — let you set a current limit directly in the app. Drop from 16A (11 kW) to 10A (7 kW) and you free up headroom for everything else.
2. Schedule EV charging at night
The simplest fix: set your charger to start after midnight and finish before 6am. Household consumption drops to almost nothing overnight — your EV charges alone and your peak stays at the minimum.
3. Use solar surplus charging
If you have solar panels, configure your charger to only draw the surplus your panels are producing at that moment. This is sometimes called 'solar-only mode' or 'green mode'. You charge for free from your own production and add zero load to your grid connection.
4. Stagger your appliances
Don't run the dishwasher, washing machine, and dryer at the same time. Spread them across different hours. The rule of thumb: if you can hear your heat pump running, avoid starting anything else with a heating element.
5. Monitor your real-time consumption
Connect to your smart meter's P1 port and monitor what's happening live. Knowing that you're currently drawing 4 kW gives you context before you plug in the car or start the oven. Awareness alone reduces peaks significantly.
The Automatic Approach
Manual rules work, but they require constant attention. A smart energy management system like Lyvra does this automatically: it reads your real-time power draw from the smart meter, knows when your EV is connected, sees what your solar panels are producing, and adjusts the charging speed in real time to keep your monthly peak as low as possible.
Lyvra users in Belgium typically maintain a monthly peak below 4 kVA — even with daily EV charging — saving €40–80/month on the capacity tariff component alone.
The automation runs continuously in the background. You don't adjust anything. The algorithm handles every 15-minute window throughout the month, so you never have to think about it again.
Is the Capacity Tariff Here to Stay?
Yes. The capacity tariff is now the structural basis of how Fluvius charges for grid access. The rationale is sound: the grid needs to be sized for peak demand, not average demand — so heavy peak users pay more for the grid infrastructure they require. As EV adoption grows, this becomes more pronounced.
The households that adapt early — either through manual discipline or smart automation — gain a sustained cost advantage over those who don't.
Summary: Your Monthly Peak Checklist
EV charging scheduled at night or limited to solar surplus
Heat pump, oven, and EV never running simultaneously at full power
Dishwasher and laundry staggered, not simultaneous
Smart meter connected and real-time consumption visible
EV charger maximum current configured, not left at factory default
If these five things are true for your household, your capacity tariff will stay at or near the minimum every month. If you'd rather not think about it at all — that's exactly what Lyvra is built for.
