A cheaper way to coat photovoltaic panels

Natcore coats textured solar cells with anti-reflective coatingNatcore Technology (TSX-V: NXT), which is developing proprietary methods of depositing anti-reflective coatings on silicon photovoltaics in ambient conditions, was able to coat textured photovoltaics with its anti-reflective coating.

The solar cells are texturized, with small pyramidal shapes in an attempt to allow them to absorb more sunlight, which could make it difficult to ensure uniform coverage with an anti-reflective coating. But Natcore said its liquid phase deposition technology, which deposits—or grows—a thin, anti-reflective coating on photovoltaics at room-temperature without the use of a vacuum or furnace, was able to effectively coat textured solar cells.

“It was a big deal because the testing results showed up a lot better than we expected,” said Chuck Provini, Natcore’s CEO. “The textured cells were even better coated than flat cells.”

“We tested the [textured wafers] and coated them and sent them NASA to test. They were tested at the NASA facility in Ohio,” Provini said. The results make the liquid deposition process more attractive, he said.

The textured cells are being used as photovoltaics continue to get thinner. They refract light into the silicon crystal across different angles, preventing the light from traveling through the cell or being absorbed, according to Natcore. The anti-reflective coating also helps the cells absorb as much light as possible.

Such coatings are usually deposited onto the cell using high-heat furnaces and other specialized equipment. But as silicon cells continue to get thinner, the high heat can warp the solar cell, reducing its efficiency, according to Natcore.

“We do our growing at room temperature,” Provini said. “The liquid bath selectively takes from the chemicals in the bath and deposits them on a wafer,” he said.

In addition to reducing the amount of expensive equipment like furnaces, the process also needs less energy. And it has very limited toxic waste, according to Provinni.

“Our catalyst will take just what it needs out of those chemicals. Once it’s done, we take it, replenish it and reuse it,” he said.

The company is expecting delivery of its first automated liquid deposition machine in six weeks, Provini said.

It will test the device and then determine whether to send it to its intended recipient, Chinese-based TLNZ Solar Technology Co. Ltd. for testing before deciding to purchase it or whether it should send another machine to the company. It’s the first sale for the company, but it has two more pending deals, according to Provini.

Image courtesy of Natcore.