Solar production tripled using 3D-printed AGILE device from Stanford University

Researchers at Stanford University 3D printing has been used to develop a new device that could help enhance the capabilities of solar arrays to capture energy and remove the need for automated tracking systems.

Shaped like an inverted pyramid without a tip, the team’s Axial Graduated Index Lens (AGILE) device captures more than 90% of the light it’s exposed to and directs it in a way that increases its brightness three times. Compared to current solar arrays, which track the sun across the sky, AGILE can also passively capture light from any angle, giving it the ability to help make solar panels smaller, cheaper and more efficient.

“We wanted to create something that takes light and focuses it in the same position, even when the source changes direction,” explains device developer Nina Vaidya. “It’s a completely passive system—it doesn’t need power to track the source or have any moving parts. Without optical focusing that drives positions or the need for tracking systems, focusing light is much simpler.”

The different stages of manufacturing a graded pointer glass pyramid: Upon optical contact with a solar cell, the pyramid absorbs in the last step (lower right corner) and concentrates most of the incident light and appears opaque.  Image via Nina Vidya.
The different stages of manufacturing a graded pointer glass pyramid: Upon optical contact with a solar cell, the pyramid absorbs in the last step (lower right corner) and concentrates most of the incident light and appears opaque. Image via Nina Vidya.

The pursuit of solar energy efficiency

Since the sunlight absorption capabilities of PV systems depend on them directly facing the sun, many are equipped with solar trackers. In a uniaxial setup, these systems rotate back and forth in one direction. On the other hand, with biaxial trackers, they tend to use a mirror to redirect sunlight toward a fixed receiver, as a means of maximizing the exposure of the lighting panel.

Both “active” systems move in tandem with the Sun, and generate more energy than stationary alternatives, but according to Stanford engineers, their construction is more expensive and more complex. To make it easier to get solar energy more efficiently, the team created a device made of a material designed to passively focus scattered light into a focal point.

Known as an AGILE, this device works like a magnifying glass, in that it focuses the sun’s rays into a smaller, brighter point, but instead of moving with the sun, it directs the rays from all angles to the same output. By replacing the silicon used to encapsulate existing solar modules with a layer of these devices, the researchers say it’s possible to generate more power from inexpensive compact solar panels.

“Often the best solutions are the simplest ideas,” explains Vaidya’s doctoral advisor Olav Solgaard. “The perfect AGILE has, at its fore, the same refractive index as air and is gradually rising – it bends light in a perfectly smooth curve.” Although he adds, “In a practical situation, you wouldn’t have that perfect style.”

Nina Vaidya measuring the experimental performance of photovoltaic concentrators under a solar simulator.  Photo by Nina Vidya.
Stanford University researcher Nina Vidya measures the experimental performance of her optical condenser under a solar simulator. Photo by Nina Vidya.

agile solar capture

In order to produce prototypes of AGILE polymer lenses in 2018, engineers used a combination of SLA and wax 3D printing. However, the team has since moved on to a method that enables glass and polymer to be deposited into a gradient indicator material, with layers able to change the direction of the light beam in steps, rather than in a smooth curve.

Using this material, researchers have now been able to create “reversed” devices, in which any light headed in the wrong direction is bounced back toward their output. During testing, these prototypes also demonstrated the ability to direct light in a way that increased its brightness three times. As such, it is argued that the devices could eventually be mounted on regular solar panels, as a way to enable them to capture light diffused in Earth’s atmosphere, weather and seasons.

According to Vaidya, the main challenge in creating such devices is crafting the right material. The plastic and glass used to make the team’s prototypes must be compatible with each other, as if one expands in response to heat at a different rate than the other, the entire device can crack. However, the team eventually came up with a formula that would allow the creation of lenses with nanometer scale features, giving them the storage space for solar panels and the power of a backlit display.

“To be able to use these new materials, these new manufacturing technologies, and the new AGILE concept to create better solar capacitors, has been very beneficial,” Vaidya concludes. “Abundant, affordable, and clean energy is a vital part of addressing pressing climate and sustainability challenges, and we need to galvanize engineering solutions to make that a reality.”

“Using our efforts and knowledge to create meaningful engineering systems has been my driving force, even when some trials have not been successful.”

Group AGILE devices into an array.  Image via Stanford University.
Group AGILE devices into an array. Image via Nina Vidya.

Solar energy storage development

A great deal of research is currently being poured into 3D-printable materials with improved solar energy storage capabilities. earlier this year, Oak Ridge National Laboratory (ORNL) announced that a team of its researchers is studying the potential of the mineral halide perovskite 3D printing of high performance solar batteries.

Similarly, the former T3DP start-up has experimented with its patented technologies for 3D printing of perovskite based solar panels. Similar to a fly-eye replica, the company’s copper-coated hexagonal scaffolding was said to be able to harness twice as much energy as traditional solar panels.

Elsewhere, the technology has also been deployed to enable the creation of solar-powered devices with applications other than clean energy generation. Researchers based in China and Singapore, for example, have 3D printed solar water purifiers At such a high level in the past, they met him World Health Organization Standards.

The researchers’ findings are detailed in their paper titled “3D printed optics with nanometer surface roughnessco-written by Nina Vidya and Olaf Solgaard.

To stay up to date with the latest 3D printing news, don’t forget to subscribe to 3D printing industry flyer or follow us Twitter Or like our page on Facebook.

To dig deeper into additive manufacturing, you can now subscribe to Youtube A channel featuring discussion, debriefing, and 3D printing shots in action.

Are you looking for a job in the additive industry? visit 3D Printing Jobs To choose roles in the industry.

Featured image shows Nina Vaidya measuring the experimental performance of photovoltaic concentrators under a solar simulator. Photo by Nina Vidya.