They replaced their fuel oil with hybrid solar energy and cut their annual bill from €4,200 to €1,500!

  • 2022
  • Allauch , France
  • Power output : 6 kWp
  • Panels : 6 hybrid + 10 photovoltaic

Frédéric lives in Allauch, between Marseille and Aubagne. In 2018, he and his wife purchased their 200m2 house, built 50 years earlier.

Because they had embarked on a comprehensive renovation project, including changing their oil-fired heating system, they came up with the idea of installing Dualsun hybrid solar and photovoltaic panels coupled with a heat pump.

A look back at this project, installed in 2022 ⬇️

We’ve more than halved our energy bill”. Frédéric

“Why not combine the renovation of our heating system with the installation of solar panels? “was Frédéric’s question when he was thinking of getting rid of his oil-fired heating system!

So, for both economic and ecological reasons, they decided to install solar panels.

A simple Internet search led Frédéric to our MyDualsun solar simulator: from there, in just a few clicks, he could configure his project and be put in touch with a partner in our network.

Today, his house is equipped with 16 solar panels: 10 FLASH photovoltaic panels for electricity and 6 SPRING hybrid panels for hot water + electricity, for a total output of 6 kWp. All coupled with a heat pump.

Solar panel inverter 


“During the summer months, even over 4 months of the year, I can produce domestic hot water without having to switch on the heat pump”. Frédéric is very happy with his installation: “Our partner installer DualSun showed a great deal of professionalism, with competent and very pleasant teams. The worksite was short and the deadlines were met, even though the project was quite comprehensive, with several types of installation to be planned, such as a heat pump, indoor and outdoor units, solar panels plus the entire network to be deployed”…

In 2021, before the solar panels were installed, Frédéric had an oil-fired heating system. As a result, the house’s energy bill (electricity+oil) came to €4,200.

In 2023, after a full year with solar panels, his electricity bill would be €2,200, minus €700 for production not consumed but sold to Enedis: a bill of €1,500.

But Frédéric and his wife have gone one step further by acquiring two electric vehicles. This represents a new source of savings, as they charge the vehicles in the middle of the day when the sun is at its zenith: no need to put petrol in, they’re running on solar power!

What are the advantages of DualSun FLASH and SPRING Shingle panels?


In terms of government subsidies, Frédéric benefited from MaPrimeRénov’ for his new heat pump, as well as a €2,500 government subsidy and a €1,900 subsidy for the resale of unused surplus energy.

When it comes to monitoring production, he regularly consults the monitoring application on which he can see the panels’ output. “For me, it’s a profitable investment: the loan we took out with the bank to finance this project has been practically wiped out by the savings we’ve made in terms of energy consumption, production and resale. I’m completely satisfied with the Dualsun solar system. One thing’s for sure: if you’re renovating and you install DualSun panels, it’ll pay for itself in no time!”

Technical information

Characteristics House
Number of panels 6 DualSun SPRING hybrid panels + 10 DualSun FLASH photovoltaic panels
Power output 6 kWp
Rooftop installation South-facing, 30° slope
Thermal system Coupling with heat pump + SPRING panels
Photovoltaic system Micro-inverters, self-consumption with sale of surplus electricity