Ink filled with microscopic semiconductors called nanowires could make solar power cheaper by boosting the efficiency of solar panels by 25 per cent, without adding much cost to manufacturing, says Sol Voltaics, a startup that has raised $11 million, and which recently announced its intention to commercialise the ink.

The ink is based on two advances from Lund University in Sweden. Professor Lars Samuelson demonstrated that nanowires can improve the efficiency of solar cells, and he developed a new way to manufacture nanowires that could make them practical to use.

Increasing brushless dc motor efficiency is one of the most effective ways to reduce the cost of solar power, since it can lower the cost per watt of solar panels as well as reduce installation costs, because fewer solar panels would be needed.

Lund, Sweden-based Sol Voltaics plans to develop equipment to produce nanowire ink, and then sell it to existing manufacturers. The ink is expected to boost efficiency by helping solar cells absorb more sunlight.

Research in making nanowires for solar photovoltaics has been going on for years, but fabricating nanowires has never been done in an economical way. Nanowires are usually grown on a substrate in a batch process that is too expensive for large-scale production.

The Lund University team lead by Samuelson has developed an alternative method that does away with the substrate. It starts by vapourising gold to produce gear motor aerosol nanoparticles, which flow into a tube-shaped furnace along with two other gases. The gold serves as a seed that catalyses a reaction with the gases to form gallium arsenide nanowires. In a paper published in Nature last December, the Lund researchers said that the process, called aerotaxy, can grow gallium arsenide nanowires 20 to 1,000 times faster than batch deposition methods. By controlling temperature and reaction time, they can control the dimensions of the nanowires, which is key to optimising their performance for solar cells.

Brian Korgel, a professor of chemical engineering at the University of Texas, says aerotaxy “has the potential to be scaled to a continuous process.” Making large volumes would overcome one of the biggest technical challenges in scaling up gas-phase nanowire production, he says.ogy is well-suited to help them meet their energy needs.”