3 patents for the module
1 patent for the panel-to-panel hookup system
+ 1,5M€ DualSun Spring sales

Bring the cost of hybrid PV modules down to promote their widespread use in the new energy-plus building landscape (new builds and renovation projects).


Distributed, modular, non-polluting energy production has long been possible thanks to solar energy systems. Today, there are two major types of solar energy equipment: solar thermal collectors, mainly used to produce domestic hot water; and solar photovoltaic panels for electricity. The Dualplas project focused on hybrid PV modules that efficiently combine both types of energy production. The purpose of the project was to lower the cost of these hybrid modules while developing a module-system pairing to meet the needs of the growing self-consumption market.

The Dualplas project kicked off in 2013, just as France’s RT2012 regulation governing building thermal performance was being implemented. The new regulation set out to reduce the energy consumption of buildings (which, at the time, accounted for 42.5% of France’s total energy consumption and generated 23% of the nation’s greenhouse gas emissions). The project consortium also kept a close watch on France’s upcoming energy-plus building regulations, slated to come into force in 2020. This future regulation will require all new buildings to produce more energy than they consume—and that energy must be clean. Given these demands, solar energy will play a leading role.

Project lead DualSun (formerly Solaire 2G) already had a hybrid PV-thermal module on the market in 2013 when the project launched. The module offered high performance. However, to prepare for the massive changes expected to transform the energy market, the company needed to bring the cost of the modules down. Back in 2013, electricity produced using solar panels was mainly sold back to the grid, guaranteeing owners a return on their investment. The future energy-plus building regulations will change this landscape.

The members of the Dualplas project consortium wanted to get ahead of the solar self-consumption market—and the lower prices that will be associated with self-consumption once the new solution is rolled out—by developing a more affordable product made using new materials and processes. Another one of the project partners’ objectives was to achieve solar self-consumption of more than 75% to maximize self-consumption and, in the process, improve the capacity of single- and multi-family dwellings to meet their own energy needs.


Results :


The project partners were also able to test the module on actual single- and multiple-family dwellings and other buildings like indoor swimming pools and gymnasiums. The tests confirmed that the module was easy to install, fully operational once in service, and effective at promoting self-consumption.



The successful completion of the Dualplas project—in the form of a new product, Spring—left DualSun in an excellent position to raise €2.4 million in capital in 2017. The company leveraged the influx of funds to boost sales. And their strategy worked, with €1.5 million in Spring sales in 2017; €2 million at end-August 2018; and a forecasted €2.5 million to €2.7 million at end-2018.

DualSun also began addressing the swimming pool market (especially individual pools) to limit their environmental impact. Spring panels function as swimming pool heaters when it is sunny, and produce the electricity used by pool equipment like pumps. Any surplus energy is fed into the home’s supply. The system is particularly widespread in Australia, where DualSun has a local partner.



People’s energy mindsets have changed substantially since the project kicked off in 2013. As the introduction of France’s 2020 energy-plus regulation draws near, DualSun is looking at even more new opportunities. The company’s DualSun Spring panel is suitable for all types of buildings that use hot water and electricity—in other words, virtually all commercial and multi-family residential buildings.

DualSun is working on expanding its product lineup, most notably by partnering with companies offering complementary technologies. Examples include DualSun’s partnerships with Daikin, which offers HVAC and cooling solutions; Heliopac, which has a 25-year track record in domestic hot water for multi-family residential properties and renewable energy; and Ökofen, a wood-pellet boiler specialist.



Bouches du Rhône General Council, Auvergne-Rhône-Alpes Regional Council, Provence-Alpes-Côte d’Azur Regional Council