Researchers at the University of Texas have announced that solar cells could soon be produced more cheaply using nanoparticle “inks†that allow them to be printed like newspaper or painted onto the sides of buildings or rooftops to absorb sunlight and convert it into solar power.
The idea is to create a manufacturing process that is ten times cheaper than the current standard, that is, gas-phase deposition in a vacuum chamber, which requires high temperatures and is relatively expensive. The system being investigated at Texas uses light-absorbing nanomaterials, which are 10,000 times thinner than a strand of hair. Their microscopic size allows for new physical properties that can help enable higher-efficiency devices. The inks could be printed on a roll-to-roll printing process on a plastic substrate or stainless steel.
Leading the research is Brian Korgel, a chemical engineer who also owns a company called Innovalight, based in California, which is producing inks using silicon as the basis. But now Korgel and his team are using copper indium gallium selenide (CIGS), which is both cheaper and kinder to the environment.
According to Korgel, CIGS has some potential advantages over silicon as it’s a direct band gap semiconductor. That means you need much less material to make a solar cell. He adds that the inks, which are semi-transparent, could help realize the prospect of having windows that double as solar cells.
The only setback is that the technology does not perform as well as it should in other to become viable. Korgel’s team has developed solar-cell prototypes with efficiencies at one percent, which is way below the 10 percent ideal. “If we get to 10 percent, then there’s real potential for commercialization,†Korgel said. “If it works, I think you could see it being used in three to five years.â€
