Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


A Light Wave of Innovation to Advance Solar Energy

TAU researchers adapt classic antennas to harness more power from the sun

Some solar devices, like calculators, only need a small panel of solar cells to function. But supplying enough power to meet all our daily needs would require enormous solar panels. And solar-powered energy collected by panels made of silicon, a semiconductor material, is limited — contemporary panel technology can only convert approximately seven percent of optical solar waves into electric current.

Profs. Koby Scheuer, Yael Hanin and Amir Boag of Tel Aviv University's Department of Physical Electronics and its innovative new Renewable Energy Center are now developing a solar panel composed of nano-antennas instead of semiconductors. By adapting classic metallic antennas to absorb light waves at optical frequencies, a much higher conversion rate from light into useable energy could be achieved. Such efficiency, combined with a lower material cost, would mean a cost-effective way to harvest and utilize "green" energy.

The technology was recently presented at Photonics West in San Francisco and published in the conference proceedings.

Receiving and transmitting green energy

Both radio and optical waves are electromagnetic energy, Prof. Scheuer explains. When these waves are harvested, electrons are generated that can be converted into electric current. Traditionally, detectors based on semiconducting materials like silicon are used to interface with light, while radio waves are captured by antenna.

For optimal absorption, the antenna dimensions must correspond to the light's very short wavelength — a challenge in optical frequencies that plagued engineers in the past, but now we are able to fabricate antennas less than a micron in length. To test the efficacy of their antennas, Prof. Scheuer and his colleagues measured their ability to absorb and remit energy. "In order to function, an antenna must form a circuit, receiving and transmitting," says Prof. Scheuer, who points to the example of a cell phone, whose small, hidden antenna both receives and transmits radio waves in order to complete a call or send a message.

By illuminating the antennas, the researchers were able to measure the antennas' ability to re-emit radiation efficiently, and determine how much power is lost in the circuit — a simple matter of measuring the wattage going in and coming back out. Initial tests indicate that 95 percent of the wattage going into the antenna comes out, meaning that only five percent is wasted.

According to Prof. Scheuer, these "old school" antennas also have greater potential for solar energy because they can collect wavelengths across a much broader spectrum of light. The solar spectrum is very broad, he explains, with UV or infrared rays ranging from ten microns to less than two hundred nanometers. No semiconductor can handle this broad a spectrum, and they absorb only a fraction of the available energy. A group of antennas, however, can be manufactured in different lengths with the same materials and process, exploiting the entire available spectrum of light.

When finished, the team's new solar panels will be large sheets of plastic which, with the use of a nano-imprinting lithography machine, will be imprinted with varying lengths and shapes of metallic antennas.

Improving solar power's bottom line

The researchers have already constructed a model of a possible solar panel. The next step, says Prof. Scheuer, is to focus on the conversion process — how electromagnetic energy becomes electric current, and how the process can be improved.

The goal is not only to improve the efficiency of solar panels, but also to make the technology a viable option in terms of cost. Silicon is a relatively inexpensive semiconductor, but in order to obtain sufficient power from antennas, you need a very large panel — which becomes expensive. Green energy sources need to be evaluated not only by what they can contribute environmentally, but also the return on every dollar invested, Prof. Scheuer notes. "Our antenna is based on metal — aluminium and gold — in very small quantities. It has the potential to be more efficient and less expensive."

George Hunka | EurekAlert!
Further information:

More articles from Power and Electrical Engineering:

nachricht Fluorescent holography: Upending the world of biological imaging
25.10.2016 | Colorado State University

nachricht Did you know that infrared heating is an essential part of automotive manufacture?
25.10.2016 | Heraeus Noblelight GmbH

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Ice shelf vibrations cause unusual waves in Antarctic atmosphere

25.10.2016 | Earth Sciences

Fluorescent holography: Upending the world of biological imaging

25.10.2016 | Power and Electrical Engineering

Etching Microstructures with Lasers

25.10.2016 | Process Engineering

More VideoLinks >>>