London, UK – August 26, 2025

A Remarkable Leap in Solar Efficiency

In a major advancement for renewable energy, researchers at the University of Rochester have engineered a new type of solar thermoelectric generator (STEG) that is 15 times more efficient than current state-of-the-art devices. The breakthrough, which could transform how solar power is harnessed, centers on a unique “black metal” technology and new thermal management techniques.

Unlike traditional solar panels that convert light into electricity, STEGs convert heat from any source, including the sun, into power. This has always been a promising but highly inefficient technology. While conventional solar panels can convert about 20% of sunlight into electricity, most STEGs convert less than 1%. This new research, published in the journal Light: Science and Applications, has dramatically narrowed that gap.

Headlines of the Report

 * 15x Efficiency Boost: A new solar thermoelectric generator is 15 times more powerful, a major step toward making the technology a viable alternative to traditional solar panels.

 * “Black Metal” Technology: The breakthrough uses a specialized “black metal” created by a femtosecond laser etching nanoscale structures into tungsten, dramatically increasing the material’s ability to absorb and trap solar heat.

 * Dual-Sided Optimization: The researchers focused on optimizing both the “hot” and “cold” sides of the device to maximize the temperature difference, which is key to generating more electricity.

 * Mini-Greenhouse Effect: A simple plastic cover over the black metal creates a “mini-greenhouse” to further trap heat and increase the device’s efficiency.

 * Broader Applications: The technology could be used to power wireless sensors, wearable electronics, and provide off-grid renewable energy.

The research team, led by Professor Chunlei Guo, achieved this remarkable increase in efficiency by focusing on the thermal aspects of the device rather than the semiconductor materials in the middle. The innovation rests on three key strategies: a laser-etched “black metal” on the hot side of the device to absorb more light and trap heat; a plastic cover over the black metal to create a mini-greenhouse that minimizes heat loss; and a new laser-etched aluminum heat sink on the cold side to improve heat dissipation.

The black metal is a unique material created by blasting a regular piece of tungsten with ultra-short bursts from a femtosecond laser. These pulses create tiny, nanoscale structures on the surface, making the material pitch-black and allowing it to absorb nearly all incoming light and convert it into heat.

The new technology could have significant implications for the future of energy generation. While traditional solar panels are limited to converting light, this new STEG technology can harness heat from a variety of sources, opening the door for new applications in industrial settings, power generation, and small-scale electronics.