Solar power is perhaps one of the most expensive renewable energy technologies today, but developments are underway to make it cheaper and more economical.

Researchers at Argonne National Laboratories and Penn State are saying that luminescent solar concentrators (LSCs) could eliminate the cost barrier.

The technology works by concentrating sunlight, thus allowing generators to produce more power using fewer solar cells. On top of that, the LSC would allow solar farms to produce power even on a cloudy day, raising the capacity factor of the solar power facilities.

"Currently, solar concentrators use expensive tracking systems that need to follow the sun," Chris Giebink, assistant professor of electrical engineering, Penn State, formerly of Argonne National Laboratory, said.

"If they are a few tenths of a degree off from perfection, the power output of the system drops drastically. If they could maintain high concentration without tracking the sun, they could create electricity more cheaply."

Smaller LSCs works better than largers ones, since more solar energy is absorbed in the latter. This is the main road block to the promotion of the technology. The researchers are now working on ways to reduce the absorption problem, by having light travel through two media.

"We were looking for some way to admit the light, but keep it from being absorbed," Giebink said.

"One of the things we could change was the shape and thickness of the luminescent layer," he added

The result of their experiments show a 15 percent increase the output, compared to traditional LSCs.

"We need to find the optimum way to structure this new type of LSC so that it is more efficient but also very inexpensive to make," said Giebink.

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