How do we calculate your scenarios?
Simple explanation of our calculation methods
Transparency First
We calculate your energy costs for each scenario based on your annual production and consumption. Below we explain step by step how each scenario works.
Our Assumptions
Energy Prices (2026-2027)
- • Import price: €0.30/kWh (fixed contract, all-in)
- • Feed-in now: €0.10/kWh (with net metering you get the import price back)
- • Feed-in after 2027: €0.0025/kWh (fixed) or ~€0.05/kWh (dynamic)
- • Fixed costs: €450/year (grid + standing charges)
How We Calculate
We calculate every hour of the year (8,760 hours):
- • Your consumption per hour (NEDU profile or evenly distributed)
- • Your production per hour (KNMI solar data + your panels)
- • Per hour: production > consumption = export, consumption > production = import
Now: With net metering
What you export up to your consumption is credited at import price (€0.30/kWh). Extra export receives €0.10/kWh.
Calculation
Example
Suppose:
- Consumption: 3,000 kWh/year
- Production: 4,000 kWh/year
- Import: 762 kWh, Export: 1,601 kWh
Calculation:
- Net metering: 762 kWh import offset by 762 kWh export = €0
- Extra export: (1,601 - 762) × €0.10 = €84 bonus
- Fixed costs: €450
- Total: €450 - €84 = €366/year
After 2027: Fixed contract (no net metering)
Without net metering, you pay €0.30/kWh for import and receive only €0.0025/kWh for export. This is the worst scenario for solar panel owners.
Calculation
Why so little for export?
Energy suppliers charge 'feed-in costs' of ~€0.05-0.10/kWh. After deduction, only €0.0025/kWh net remains. That's why a fixed contract is unfavorable after 2027.
After 2027: Dynamic contract
With a dynamic contract, you pay the market price per hour. The big advantage: you also receive the market price for export (~€0.05/kWh average during solar hours). That's 20× more than fixed contracts!
Calculation
How do dynamic prices work?
- • We use real ENTSO-E market prices from the past year
- • Import: market price + €0.12 supplier costs
- • Export: only the market price (no costs)
- • Average export price: ~€0.05/kWh during solar hours
Extra savings through smart consumption
By running dishwasher, washing machine and EV during cheap hours you save extra:
- • Standard household: 15% of consumption is flexible. Savings: €20-50/year extra.
- • With EV or heat pump: 35% of consumption is flexible. Savings: €50-150/year extra.
Fixed contract + battery
With a battery, you increase self-consumption from ~30% to 60-80%. You import less and only export when the battery is full.
How the battery works
- Daytime: excess solar charges the battery
- Battery full? Rest goes to the grid (€0.0025/kWh)
- Evening: battery powers your home
- Battery empty? Then you import from grid
Calculation
Battery assumptions
- • Capacity: 10 kWh (8.5 kWh usable)
- • Efficiency: 90% (10% loss per cycle)
- • Self-consumption: from ~30% to 60-80%
Self-consumption calculation
Self-consumption = how much of your solar energy you use yourself. We simulate every hour of the year.
The simulation
- Each hour: production > consumption? Charge battery
- Battery full? Export to grid
- Consumption > production? Discharge battery
- Battery empty? Import from grid
We account for 10% loss per charge/discharge cycle
Example
Typical household with solar panels:
- Production: 5,000 kWh/year
- Consumption: 4,600 kWh/year
Without battery:
- • Self-consumption: 2,450 kWh (49%)
- • Export: 2,550 kWh
- • Import: 2,150 kWh
Cost: 2,150 × €0.30 - 2,550 × €0.0025 + €450 = €1,089/year
With 10 kWh battery:
- • Self-consumption: 3,500 kWh (70%)
- • Export: 1,500 kWh
- • Import: 1,100 kWh
Cost: 1,100 × €0.30 - 1,500 × €0.0025 + €450 = €776/year
Why does a battery help?
The battery stores excess solar energy during the day (when production peaks) for use in the evening (when consumption peaks). This reduces expensive imports from €0.30/kWh and avoids selling at the low €0.0025/kWh export rate.
Savings: €313/year
(€1,089 - €776 = €313 per year)
Dynamic contract + battery
Combines market prices with smart battery control. The battery charges during cheap hours and discharges during expensive hours.
Smart charging strategy
- First: charge from free solar energy
- Also: charge from grid at low prices
- Discharge during peak prices
Calculation
Price arbitrage explained
With a dynamic contract, the battery can 'buy low, sell high'. This means:
- 1. Charge when prices are low (often at night or solar peak hours)
- 2. Discharge when prices are high (typically 17:00-21:00)
- 3. After 10% battery losses, this is profitable when price difference > 15%
Note: the average export price with 'dynamic + battery' may be slightly lower than with 'dynamic only'. This is because the battery stores energy during the highest prices. Export only occurs when the battery is full, usually during the lowest price moments.
Our Data Sources
Questions? Check our FAQ or contact us.
Calculate your personal savings
See exactly how much you can save after the end of net metering. Free, independent, and based on your situation.
Start Free Analysis ↗