Free hour-by-hour self-consumption simulator (with your Linky curve)
calcul-solaire.fr matches your solar production against your consumption over the 8,760 hours of the year. For a typical household in Lyon with 3 kWp installed, actual self-consumption ranges from 20 to 53% depending on whether someone is at home during the day; a monthly balance would give 88%.
- →The simulator calculates self-consumption hour by hour, over 8,760 steps, for free, with no account, email or phone number.
- →A monthly balance counts midday production as if it covered evening consumption: it gives 88% where the typical household actually self-consumes 20 to 53%.
- →What decides the rate is presence during the day and the installed capacity, not sunshine alone.
- →With the export from your Linky smart meter, the simulation starts from your measured consumption, hour by hour.
Why does a monthly balance get it wrong?
Solar panels generate mostly between 10:00 and 16:00. A household consumes a lot in the morning, in the evening and at night: cooking, lighting, hot water during off-peak hours. Only the electricity generated at the moment the home needs it is self-consumed; the rest goes to the grid.
A monthly balance adds up the month's generation and the month's consumption, then keeps the smaller of the two. It acts as if the midday sun were powering dinner. The result is wrong in the same way every month, and it inflates the stated saving, because a self-consumed kWh is worth the price of the EDF regulated “tarif bleu” whereas an exported kWh is bought back at only 0.011 €.
By how much does a monthly balance overstate self-consumption?
We ran the simulator's engine on a typical household using 4,500 kWh a year (3 people, 100 m², non-electric heating, electric hot water cylinder) in Lyon, with a south-facing roof tilted at 30°. Same hourly series, three ways of doing the balance: hourly, monthly, annual.
| Household | System size | Actual (hour by hour) | Monthly balance | excess kWh | Overstated saving |
|---|---|---|---|---|---|
| Absent en journée | 3 kWp | 20%786 kWh | 88%3,523 kWh | 2,737 kWh | 518 €/year |
| Absent en journée | 6 kWp | 12%996 kWh | 53%4,207 kWh | 3,211 kWh | 607 €/year |
| Télétravail 2 à 3 jours par semaine | 3 kWp | 43%1,703 kWh | 88%3,524 kWh | 1,821 kWh | 344 €/year |
| Télétravail 2 à 3 jours par semaine | 6 kWp | 26%2,045 kWh | 53%4,199 kWh | 2,154 kWh | 407 €/year |
| Présent toute la journée | 3 kWp | 53%2,125 kWh | 88%3,522 kWh | 1,397 kWh | 264 €/year |
| Présent toute la journée | 6 kWp | 31%2,443 kWh | 53%4,209 kWh | 1,766 kWh | 334 €/year |
Percentages: share of generation consumed on site. Overstated saving: excess kWh counted × (price per kWh at the EDF regulated “tarif bleu” Base rate − buy-back rate for surplus). Calculated on 8 October 2026 ; an annual balance goes even further, counting all the generation as self-consumed.
Two lessons. First, the monthly balance cannot tell an absent household from one at home: it gives them the same rate, even though one self-consumes more than twice as much as the other. Second, the gap widens with system size: doubling the panels mostly increases the surplus, which only an hourly calculation reveals.
How do you simulate with your Linky curve?
An estimated profile remains an assumption. If your Linky meter records your consumption hour by hour, the simulator can start from the measurement:
- On your Enedis customer account (Enedis is the grid operator), in the consumption tracking section, export your hourly consumption as a CSV file for the last 12 months.
- In the simulator, at the “Consumption” step, choose “I have my Linky export” and upload the file.
- The simulation then compares your measured consumption with the generation from your roof, hour by hour.
How does the simulator calculate hour by hour?
- Generation: PVGIS 5.3 typical year (European Commission) at the coordinates of your roof, transposed onto each roof face, and corrected hour by hour for module temperature, the inverter and shading.
- Consumption: rebuilt item by item (heating, hot water, cooking, appliances) from your answers and your presence at home, or measured by your Linky meter.
- Balance: for each of the 8,760 hours, the share consumed on site is the minimum of generation and consumption; the rest is exported or bought.
The formulas, constants and known limitations are published on the technical methodology page and explained in our methodology.
Frequently asked questions
Is there a free hour-by-hour self-consumption simulator?▾
Why calculate hour by hour rather than month by month?▾
What self-consumption rate should I expect?▾
How do I use my Linky curve in the simulation?▾
Is the hour-by-hour calculation reliable?▾
What self-consumption will YOU get?
Your roof, your consumption, hour by hour. Free, no sign-up, no email or phone number.
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