Soterna's Solar Thermal Boiler Uses Radel® PPSU for High Strength and Resistance to Hot Chlorinated Water

PPSU Replaces Stainless Steel in Pressurized Solar Panel System

ALPHARETTA, Ga., - Soterna S. Coop., based in Navarra, Spain, has developed the first solar panel system with an integrated thermal boiler for quick installation and reduced cost. The thermal boiler is made of Radel® polyphenylsulfone (PPSU) resin from Solvay Specialty Polymers USA, LLC, which provides long-term hoop stress resistance along with resistance to prolonged exposure to hot chlorinated water.
Soterna's decision to go with PPSU instead of the traditional stainless steel represents the first use of a thermoplastic for thermal boilers in a pressurized solar panel system. "We needed a partner with a raw material that offered strength and long-term durability, coupled with a history on the market," said Asier Juaristi, managing director of Soterna. "Solvay's know-how was essential to this development." Powered by a photovoltaic solar cell, the integrated solar thermal system uses solar energy to produce hot water.

"We worked closely with Soterna in a multi-year project that successfully adapted polymer technology to solar thermal systems through multiple processing trials and product development efforts," said Doug Brademeyer, vice president of sulfone-based polymers for Solvay Specialty Polymers. This unique application is also a key part of Solvay's sustainability strategy which focuses on the development of material solutions for the alternative energy market and other industries.

The 80 kg (176.5-lb) thermal complete system - measuring 2029 mm by 1020 mm by 240 mm (80 in. by 40 in by 9.5 in.) - withstands high pressure 600 kPa (6 bar) and hot 95°C (203°F) chlorinated water. It consists of two extruded profiles with injection molded end caps which are welded onto the profiles. The profiles are connected to each other and hold a total of 150 liters (40 gallons) of water.

The integrated thermal system reduces installation time by 50% and cuts cost due to the elimination of piping from the boiler to the panel. Targeted for residential use, the compact solar thermal system takes up no space in the dwelling and requires no maintenance.

Several Soterna solar thermal systems have been installed and are undergoing testing in Europe.

Radel PPSU has a proven track record in stringent plumbing/water handling applications for more than 10 years and offers end users a reliable and cost-effective material solution for a range of uses.

Along with Radel PPSU, Solvay offers a broad range of high-performance plastics for water handling systems, with a large number of products for fittings, including Udel® PSU, Radel® PPSU, and Solef® PVDF, as well as Polidan® PEX for pipes.

About Soterna S. Coop.

Soterna is a cooperative enterprise that is owned by the Mondragon Group. Located in Navarra, Spain, the company develops integrated solar collectors that use solar energy to produce hot water. The solar panel system is an integrated system powered by a photovoltaic solar cell and a storage tank of 150 liters. For more information, visit

About Solvay Specialty Polymers

Solvay Specialty Polymers manufactures more products with more performance than any other polymer company in the world. The company supplies over 1500 products across 33 brands of high-performance polymers - fluoropolymers, fluoroelastomers, fluorinated fluids, semi-aromatic polyamides, sulfone polymers, aromatic ultra polymers, high-barrier polymers and cross-linked high-performance compounds - for use in Aerospace, Alternative Energy, Automotive, Healthcare, Membranes, Oil & Gas, Packaging, Plumbing, Semiconductors, Wire & Cable, and other markets. Learn more at

Solvay is an international chemical Group committed to sustainable development with a clear focus on innovation and operational excellence. Its recent acquisition of specialty chemicals company Rhodia created a much larger player which is realizing over 90% of its sales in markets where it is among the top 3 global leaders. Solvay offers a broad range of products that contribute to improving quality of life and its customers' performance in markets such as consumer goods, construction, automotive, energy, water and environment, and electronics. The Group is headquartered in Brussels and its companies employ about 30,000 people in 55 countries and generated EUR 12 billion in sales (pro forma) in 2010. Solvay SA is listed on NYSE Euronext (SOLB.BE - Bloomberg: SOLB.BB - Reuters: SOLBt.BR).

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