36h
planned ahead
15min
between plans
4
devices in one plan
3min
until Victron is back on your settings after an outage
What it does with your Victron
In the high rate the house runs on the battery.
It recharges cheaply or from the sun.
Solar power stays at home.
Store the surplus first, sell it last.
Heating and hot water when power is cheap.
Always within the temperatures you set.
The car is full in the morning.
At the lowest price, or right away when you are in a hurry.
How the Victron battery control works
It sees the whole house.
Battery, sun, grid per phase, heat and car. Every 10 seconds.
It knows what is coming.
Prices from your tariff, sun for your roof, consumption the way your house really lives.
It plans 36 hours.
In quarter hours: when to charge, when to heat, when to charge the car.
The AI watches the details.
Morning fog, sauna in the evening, car on the road. It may only fine-tune the plan, it never switches anything on itself.
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It sees the whole house.
Battery, sun, grid per phase, heat and car. Every 10 seconds.
House overview: battery, grid, sun, load, price, hot water, car It knows what is coming.
Prices from your tariff, sun for your roof, consumption the way your house really lives.
Price per kWh today and tomorrow, with high and low rate It plans 36 hours.
In quarter hours: when to charge, when to heat, when to charge the car.
36-hour plan: grid, battery, sun, consumption and state of charge The AI watches the details.
Morning fog, sauna in the evening, car on the road. It may only fine-tune the plan, it never switches anything on itself.
AI advisor: what it sees, what it adjusted and why
House overview: battery, grid, sun, load, price, hot water, car
Runs our own home. Every day.
A family house in Slovakia: since October 2026 Gridzilla has run it around the clock, without intervention.
79kWh
Victron battery
26.1kWp
solar
8
underfloor heating zones
2
electric cars
“It does exactly what I would do by hand. Only it does it every 15 minutes and tells me why.”
What it saves
Simulation on a year of real hourly data from our reference house (2025) with real day-ahead market prices (EPEX, German bidding zone) and a dynamic tariff. The plan is recomputed every hour and the forecasts are wrong the way they are in real life.
around 5 %
of the electricity bill on a dynamic tariff, compared with a normally configured Victron ESS
On a dynamic tariff most of it comes from the car: it charges in the cheapest night hours instead of right away in the expensive evening. With a flat price there is nothing to shift. On a two-rate tariff the battery itself does the work, mostly from November to February.
The Home plan costs 46.80 € a year. A typical house saves more than that, and if it does not, we refund the difference.
Large house, dynamic tariff
39 MWh, heat pump, 79 kWh battery, two electric cars
≈ 330 €
Typical house, dynamic tariff
11 MWh, heat pump, 15 kWh battery, one electric car
≈ 100 €
Typical house, two-rate tariff
Slovak example: the high rate 4 hours a day runs from the battery, recharged in the low rate.
60 – 90 €
Reference house: PV 26.1 kWp, Viessmann Vitocal 300 heat pump, two electric cars, 39 MWh a year. Dynamic price: market price plus 19 ct grid fees, levies and margin, plus 19 % VAT; feed-in 7.9 ct, zero at negative prices. Every house is different. We estimate yours from your VRM data for free.
You have the last word.
First it only watches.
You switch control on once you see what it would do.
An outage breaks nothing.
Within 3 minutes Victron is back on your settings.
The battery is safe.
Never below the minimum, never sold from the battery to the grid.
Runs in your home.
No third-party cloud, your data stays yours.
Gridzilla pricing
Monthly subscription, no setup fee. You pay the first year up front, then monthly, and you can cancel any time.
Home
Most popularBattery up to 15 kWh
3.90 €
a month · incl. VAT · 3.17 € net
first year up front: 46.80 €
- Battery and solar
- Your tariff: two-rate, fixed or dynamic
- Heat pump and hot water
- EV charging
- AI advisor and 36-hour plan
- Remote setup, updates, support
Large home
Battery over 15 kWh or consumption over 20 MWh
9.90 €
a month · incl. VAT · 8.05 € net
first year up front: 118.80 €
- Everything in Home
- Underfloor heating by zone
- Several cars and chargers
- Two weeks of fine-tuning on your data
- Priority support
Savings guarantee
If Gridzilla saves you less in the first 12 months than you paid for them, we refund the difference. The savings are measured daily and shown in the overview.
- All prices include 23 % Slovak VAT (the service is provided from Slovakia). You need a Victron Cerbo GX and an internet connection.
- If needed, we supply a ready-made mini PC: 270.60 € incl. VAT (220 € net).
- Custom work: 147.60 € incl. VAT (120 € net) per hour, with an estimate up front.
- Customers from any EU country can order. The same service is offered in Slovak and in German.
- Terms and conditions
Guides to Victron energy management
- Read more
Victron battery on a dynamic tariff: what it really saves
Dynamic tariffs like Tibber or aWATTar promise cheap power in the right hours. We worked out how much of that actually reaches a house with a Victron battery.
- Read more
Setting up Victron ESS properly: the settings that really count
A Victron ESS already does a lot right without extra software. A few settings are often misunderstood, though, and cost money. We learned this running our own system.
- Read more
PV surplus charging with the Victron EV Charging Station
In Auto mode the Victron EV Charging Station can charge on solar surplus only. For that to really work you need to know three settings.
- Read more
PV forecasts in fog: why weather models get winter wrong
A battery controller is only as good as its PV forecast. In valleys with winter fog all the major weather models are regularly wrong. We measured by how much, and what helps.
Frequently asked questions about Victron battery control
What does Gridzilla work with?
Victron ESS on a Cerbo GX: MultiPlus-II or Quattro, MPPT and a battery with BMS. Viessmann heat pumps, TECH room controllers, the Victron EV Charging Station and Tesla are ready; we connect others on request.
I have a two-rate tariff, not spot prices. Is it worth it?
Yes, if the two rates differ clearly. The house gets through the high rate on the battery and recharges in the cheap hours or from the sun. With a flat price there is nothing to shift. With spot prices it plans by every quarter hour as well.
How much will I save?
A typical house with a 10 to 15 kWh battery saves roughly 60 to 90 € a year on a two-rate tariff and around 100 € on a dynamic tariff, about 5 to 15 % of the electricity bill. Our large house with a 79 kWh battery saves 170 to 330 €. It depends on your tariff, battery and what we control, so before you order we estimate it from your VRM data.
Does it work with Tibber and other dynamic tariffs?
Yes. Gridzilla plans on the day-ahead market prices that Tibber, aWATTar and similar tariffs are based on, and charges the battery and the car in the cheapest hours.
Do I need Node-RED or Home Assistant?
Not Home Assistant. On the Cerbo GX (Venus OS Large) we set up a small Node-RED flow through which Gridzilla changes the ESS settings safely. You do not program anything.
How does the subscription work?
You pay the first 12 months up front; that covers the setup. After that the subscription runs monthly and you can cancel any time to the end of the month. If it saves less in the first year than you paid, we refund the difference.
What if the internet goes down?
Victron returns to your settings within 3 minutes and carries on as before. The planning runs in your home.
Who is behind Gridzilla?
VictronLab, a brand of Tekvica, s. r. o. from Slovakia. We program control for Victron systems. Gridzilla is not a Victron Energy product; it uses the public interfaces of their devices.
Tell us about your system.
Within two working days we reply with a recommendation and an estimate.