Hello, I'm Bastien. A photovoltaic engineer, and the only one at the controls of this simulator.
I built calcul-solaire.fr to give households what engineering firms usually keep for professionals: a rigorous, transparent simulation, with no sales calls and no commercial middleman.
Solar deserves better than sales pitches.
I have spent the last 8 years managing photovoltaic and energy performance projects for households in various French cities, from Paris to Marseille, by way of Toulouse and Rouen.
In the field, I saw the same thing happen again and again: households often keen on the idea and ready to go ahead, but poorly informed, or not informed at all. Sometimes the merits of solar were oversold to them and they were promised an autonomy or independence that was completely out of reach. Sometimes they were sold an oversized installation that did not suit their consumption at all. Often they are not given the right data or the concrete results they could achieve, or only in a rushed and inaccurate way. And sometimes, to top it all, they are made to sign an order form with no right of withdrawal, at a far too high price, with a consumer credit offer attached.
The problem is not solar: the technology is mature, profitable and beneficial. The problem is the information gap. A household that sizes its installation blindly will almost always pay too much for badly calibrated power.
I built calcul-solaire.fr to close that gap: tools and a precise, documented methodology (PVGIS, hourly calculation over 8,760 steps, self-consumption modelling), but for everyone, available in 5 minutes, free of charge, and without a salesperson calling you back afterwards.
My goal is not to sell panels. It is to give you the figures you need to decide, and to tell you honestly when solar is not worthwhile for your roof.
Five stages, a single path: making energy understandable.
From technical feasibility to operational management, every role reinforced my conviction that households were missing a neutral tool.
- 2013 – 2018
Engineering degree, Energy & Environment
Five years of study and a specialisation in Energy and Environment in Buildings.
- 2018 – 2020
Solar project manager
For two years I managed photovoltaic projects for households, mostly on detached houses, from feasibility to the works phases. I worked in coordination with the technical and sales teams and partner installers.
- 2020 – 2021
Renovation operations officer
I also began supporting energy renovation projects, help for people losing their independence and major refurbishment, putting together ANAH (the French national housing agency) funding applications and grant files.
- 2021 – today
Renovation & photovoltaic project manager
As a France Rénov' adviser (the French public service for home renovation advice), I support households as part of this public service mission. I manage energy renovation and therefore also photovoltaic projects, from the study to the works. I analyse quotes and studies, help with financing and put people in touch with the right craftspeople. I also regularly run training sessions for the general public or for professionals.
- 2026 →
Launch of the independent simulator
Launch of this photovoltaic simulator for the general public, based on the methods used in engineering firms: free, with no sales calls and no commercial data collection.
A tool and a platform that answer your questions.
The calculation engine of calcul-solaire.fr relies on the same methods as those used in engineering firms, adapted for the general public, without sacrificing any rigour.
Calculation method
- Hourly calculation over 8,760 time steps
- Hourly weather data matched against the consumption profile you entered
- Annual degradation of the panels taken into account (0.5%/year)
- French climate zones H1 / H2 / H3
- Economic projection over 25 years
Sources & data
- PVGIS 5.3 irradiation, European Commission
- CRE tariffs (French energy regulator) updated every quarter
- Incentives and grants from ADEME & RTE (French energy transition agency and grid operator)
- French regulatory framework (S21, self-consumption decree)
- All assumptions explained in the report
Support
- Analysis of installers' quotes
- Personal follow-up of your project
- Personal reply within 48 h (no chatbot)
- Neutral advice, with no commission and no sales calls
What you can expect from me.
Complete neutrality and independence
On calcul-solaire.fr, the simulation and the full report are free, with no account, no e-mail and no phone number. No simulation or contact details are passed on to an installer or sold, and the site takes no commission (privacy policy, sections 3 and 7).
Transparent calculations
All the assumptions are explained in the report. The sources (PVGIS, ADEME, RTE) are cited. You can cross-check every figure against an installer's quote, or come back to me if you have a question.
Teaching first
My job is to explain solar to elected officials, building managers and households. The simulator carries on that work of making things understandable, without condescension and without needless jargon.