Pushing the envelope on solar collector design
Solar collectors are a highly efficient solution for meeting heat demand through renewable energy. The use of specialty polymers versus metal brings advantages in terms of design flexibility and cost-effectiveness during the design and service life of solar thermal collectors. Inaventa Solar places great emphasis on leading-edge R&D, and their solar collector technology is the first of its kind globally. When combined with Syensqo's commitment to driving innovation to create sustainable solutions, the result was the development of a customized polymer to meet the superior performance requirements of this highly innovative device.
Tailored materials and processing
Inaventa Solar required a polymer for their absorber layer that did not exist on the market. The company initially began its metal replacement project with other polymers, but the materials failed to meet critical performance requirements. So they turned to Syensqo, launching a collaboration on the development of an extrudable, high-temperature resistant Ryton® PPS grade, a product that Syensqo could supply in industrial quality and volumes. Together, Inaventa Solar and Syensqo are using new materials and production methods to create the most competitive solar collectors and solar heating systems on the market.
Inaventa Solar is the first manufacturer of solar collectors on the market to own the technology and production methods required to make high-quality solar collectors based on heat-resistant polymers. Metal solar collectors are produced individually and in fixed sizes. Switching to high-performance polymers increases production efficiency and design flexibility, meaning that the products can be offered at lower prices with a higher degree of customization. As a result, these collectors are no longer restricted to the roof, but can also be installed as a vertical wall cover, facilitating significantly greater production of hot water for sanitary use, if needed. Unlike the manual effort required to assemble metal collectors, high-performance polymers can be extruded. Extrusion is an efficient process that can run continuously (24/7 if desired), enabling high-volume production and the reuse of scrap material.
Ryton® PPS: a strong combination of properties for more flexible solutions
Through strong collaboration, Syensqo and Inaventa Solar successfully developed a custom-tailored, impact-modified Ryton® PPS blend for the solar thermal collector absorber. The product combines high-performance in-use characteristics inherent to Ryton® PPS with the cost-effectiveness and design freedom of extrusion, enabling the development of larger and high-heat-resistant solar panels.
With long-term heat resistance up to 160°C, hydrolytic stability and dimensional stability, the new Ryton® PPS extrusion grade fulfills the requirements of Inaventa Solar’s collector design. The Ryton® PPS thermal absorber consists of an extruded twin wall sheet (Ryton® XE4510BL) and injection molded end caps (Ryton® XE5430BL) that are joined via infrared welding.
The extruded twin wall sheet consists of a row of small parallel channels and can be cut to the desired length. The collector frame is made of aluminum, and the cover can be either polycarbonate or glass.
Typical properties Ryton® XE4510BL
(10% GF, high viscosity extrusion grade)
| Property | Unit | Ryton XE4510BL |
| Tensile strength | MPa | 80 |
| Tensile elongation at break | % | 3.6 |
| Tensile modulus | MPa | 4400 |
| Flexural strength | MPa | 120 |
| Flexural modulus | MPa | 4000 |
| Izod Impact Unnotched | kJ/m² | 40 |
| Izod Impact Notched | kJ/m² | 13 |
| Density | g/cm³ | 1.3 |
Economically improving society’s carbon footprint
As builders and consumers increasingly seek opportunities to reduce their carbon footprint, the Syensqo-Inaventa solution offers great promise. In addition to cost-performance advantages, Inaventa collectors are lighter, which simplifies transport and handling on the construction site and saves energy even before they are installed. Advanced polymer solar collectors are also better suited for building integration, where solar collectors can replace other cladding and make roofs and facades active energy producers.
The main reason for replacing metals with polymers in our business is linked to the goal of making solar collectors with a lower carbon footprint.
