Solar Coatings Highlighted At Intersolar North America

The 2014 Intersolar North American trade show held in July in San Francisco included coatings from a number of companies targeting glass, plastic and metal performance. Most of these products are being used to extend the lifetime and reduce operations and maintenance costs of solar panels, metal foundations and other elements of solar arrays.

One coating that was new to the show this year is the Magnelis steel coating from ArcelorMittal, based in Chicago, which provides a self-healing corrosion-resistant surface that is superior to heavy grades of galvanization. Magnelis slows zinc runoff in comparable weathering of galvanized steel by a factor of four, thanks to a three percent magnesium addition. The Magnelis ZM310 coating is 25 micrometers thick, between two and four times thinner than a conventional galvanized steel coating.

A leading solar racking company utilizing Magnelis for the first time is Mounting Systems, of West Sacramento, which is roll forming steel instead of using aluminum, according to Don Massa, the product manager for the company’s Sigma Steel line. “Because the coating is self-healing, we can apply it before the roll forming,” he says. The forming of the struts permits the company to include a bolt-head slot that reduces parts. And the strength of the engineered strut enabled them to substitute a four inch steel strut for a six or eight inch aluminum purlin used in older designs.

Later this year, a waterborne polyvinylidene fluoride (PVDF) coating for solar panel back sheets will be developed by Solvay, complementing the company’s roll sheets, noted Philippe-Jacques Leng, the company’s global marketing manager for specialty polymers. Solvay, based in Brussels, produces a wide line of fluorinated polymers used in panel manufacturing, coatings for other balance-of-system components and for maintenance of solar arrays.

Among related solar products, Solvay also demonstrated its new Halar 500 ethylene chlorotrifluoroethylene (ECTFE) resin, which is being utilized to produce a plastic front sheet that replaces the traditional glass sheet of a solar panel. Melbourne-based Amcor has used the resin to develop flexible front sheets that will facilitate the integration of PV modules into more complex shapes, the company notes.

Arkema is also considering a waterborne version of its Kynar PVDF back sheet product for use in final coating solar panels, according to Bernard Schlinquer, the global business manager for photovoltaics at the company, based in Cedex, France. Arkema holds a patent for UV curable PVDF, which would typically be the outer layer of a solar panel back sheet, bonded by a curable adhesive to an inner polyester terephthalate (PET) layer on the solar cells. Arkema currently offers its resin-based Kynar500 for aluminum, galvanized steel, and aluminized steel surfaces in buildings.

Cybrid Technologies also displayed its spray-on self-healing solution for scratch-damaged solar panels at the show. The Wujiang-based company also offers adhesive tapes for sealing solar panels in various stages of production, notes Eric Yang, a company representative.

Other PVDF suppliers include: 3M; Shanghai 3F New Materials; Zhejiang Juhua;  Shandong Dongyue Chemical; Jiangsu Meilan Chemical; Daikin and Kureha.