This project in photos!
Are Dualsun solar panels suitable for multi‑family buildings?
Absolutely. We have already completed several collective installations, including one on a municipal campsite and another at the Bouygues Construction headquarters in the Paris region.
Because a Dualsun hybrid panel produces both electricity and heat on the same surface, it occupies far less roof area than separate photovoltaic and thermal modules installed side by side—a decisive advantage for apartment blocks, where rooftops are often crowded.
The system also matches occupants’ hot‑water and electricity needs perfectly. The 73‑unit SOGIMA residence on Avenue Pasteur in Marseille’s 7th district is a prime example.
The array combines Dualsun panels with two Heliopac water‑to‑water heat pumps. Running the solar loop at low temperature maximises efficiency and maintains high solar coverage even in winter—this configuration is marketed as “Heliopacsystem+.”
After a full year of monitoring, solar energy covered 79 % of domestic hot‑water demand in summer and 68 % in winter despite lower temperatures. All photovoltaic electricity is self‑consumed on site, cutting the residence’s non‑renewable energy use for hot water by a factor of four.
The results have exceeded our expectations.
High‑performance solar energy for every tenant
SOGIMA (Marseille’s municipal housing authority) is the city’s largest landlord, managing more than 6,700 dwellings.
Completed in 2013, the Pasteur residence was one of our first projects—and the very first Dualsun hybrid installation on a multi‑family building. SOGIMA’s technical department immediately embraced the Heliopacsystem+® solution (Dualsun panels coupled with Heliopac water‑to‑water heat pumps) and offered this property as a pilot site.
Today, 72 % of the building’s domestic hot‑water demand is covered by solar energy—clear proof of the system’s success.
Funding and support
The Capenergies competitiveness cluster played a decisive role by labelling the project as early as 2010, helping to secure public support.
The installation was co‑financed by the Provence‑Alpes‑Côte d’Azur Region and ADEME (the French Environment & Energy Management Agency).
In November 2012, SOGIMA also won EDF’s Fonds & Innovation award, receiving a €15,000 grant.
Installation: coordinated expertise
A project of this scale required strict coordination across multiple trades:
•Sénergies handled rooftop installation and PV wiring.
•SOGIMA’s technical team managed plumbing works, including solar pipework, storage tanks and heat pumps.
•Heliopac commissioned the thermal system, while SOGIMA’s heating division was trained to handle ongoing maintenance.
The result: a robust, collective solar solution that has been delivering reliable energy savings to all residents for more than a decade.
