NALSUN-NG Solar Coating Tech Transfer

Bengaluru, Jun 23 (PTI) CSIR-National Aerospace Laboratories (CSIR-NAL) on Monday announced the successful technology transfer of its next-generation solar absorber coating, NALSUN-NG, to Helix Solar Private Limited, an emerging clean-tech start-up based in Mysuru.

A formal agreement in this regard was signed, the organisation said.

"This latest transfer marks a significant step towards self-reliance in solar thermal technologies, supporting national initiatives such as Make in India, Atmanirbhar Bharat, and the National Solar Mission. The technology enables domestic manufacturing of flat plate solar water heaters, potentially reducing monthly imports of 5-6 lakh evacuated tube collectors," CSIR-NAL said in a statement.


According to CSIR-NAL, NALSUN-NG is a breakthrough graphene oxide-based solar selective coating, specifically engineered for photothermal applications such as solar water heaters.

Developed entirely in-house by CSIR-NAL, it is the first eco-friendly, water-based coating of its kind in India.

Unlike traditional coatings that rely on Volatile Organic Compounds (VOCs) and flammable solvents, NALSUN-NG uses only non-toxic inorganic materials that are compliant with the Restriction of Hazardous Substances (RoHS) and Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) standards.

"Most current commercial coatings use capital-intensive Physical Vapour Deposition (PVD) techniques or contain harmful VOCs. In contrast, NALSUN-NG requires minimal infrastructure investment, has no flammable components, and poses no effluent treatment challenges—making it ideal for local manufacturing and rural deployment," the statement added.