Featured Research

from universities, journals, and other organizations

New European Record Efficiency For Solar Cells Achieved: 39.7%

Date:
September 25, 2008
Source:
Fraunhofer Institute for Solar Energy Systems
Summary:
At 39.7% efficiency for a multi-junction solar cell, researchers at the Fraunhofer Institute for Solar Energy Systems have exceeded their own European record of 37.6% which they achieved just a short time ago. III-V semiconductor multi-junction solar cells are used in photovoltaic concentrator technology for solar power stations.

At 39.7% efficiency for a multi-junction solar cell, researchers at the Fraunhofer Institute for Solar Energy Systems ISE in Freiburg have exceeded their own European record of 37.6% which they achieved just a short time ago. III-V semiconductor multi-junction solar cells are used in photovoltaic concentrator technology for solar power stations.

Related Articles


“We have improved the contact structures of our solar cells,” says Frank Dimroth, Head of the III-V – Epitaxy and Solar Cells Group at Fraunhofer ISE. “As a result, using the same semiconductor structures, we now achieve the higher efficiency when converting sunlight into electricity.”

For the utilization in photovoltaic concentrator systems, the optimal efficiency of multi-junction solar cells must often be achieved between 300 - 600 suns, that is, at a sunlight concentration factor of 300 – 600. The metallization of the front side makes the main difference for different concentration factors. In the front grid the current is conducted through a network of thin wires from the middle of the solar cell to the edge, where it is then picked up by a 50 µm gold wire. Particularly under concentrated sunlight, the structure of this metal network is decisive.

For one, the metal wires must be big enough to transport, with low resistance, the large currents which are generated under concentrated sunlight. On the other hand, the wires must be as small as possible since the sunlight cannot penetrate through metal and thus the cell area covered by metal cannot be used for the electrical conversion.

For the past two years at Fraunhofer ISE, work is being performed on a new program for the theoretical calculation of optimal contact structures. Based on this work sponsored by the EU Project Fullspectrum (SES6-CT-2003-502620), solar cells holding the newest record efficiencies were developed. These cells are especially suitable for situations of inhomogeneous radiation, as occurs in the case of concentrated sunlight. These solar cells are installed in the concentrator modules of the type FLATCON® at Fraunhofer ISE and at the spin-off company Concentrix Solar GmbH, among others.

“We are very pleased to have advanced a further decisive step in such a short amount of time,” says Dr. Andreas Bett, Department Head at Fraunhofer ISE. “Highest conversion efficiencies help the young technology to become market competitive and to further sink the costs of generating electricity from the sun for the future.”

For more than ten years, researchers at Fraunhofer ISE have been developing multi-junction solar cells with highest efficiencies. One emphasis here is on the so-called metamorphic (lattice mismatched) triple-junction solar cells made out of Ga0.35In0.65P, Ga0.83In0.17As and Ge, which have an especially high theoretical efficiency potential. The solar cell structures consist of more than 30 single layers, which are deposited on a germanium substrate by means of metal-organic vapour-phase epitaxy (MOVPE).

Today such multi-junction III-V semiconductor solar cells achieve the highest conversion efficiency worldwide by far. Due to the large material and manufacturing costs, however, they are only used in concentrating PV systems and in space.


Story Source:

The above story is based on materials provided by Fraunhofer Institute for Solar Energy Systems. Note: Materials may be edited for content and length.


Cite This Page:

Fraunhofer Institute for Solar Energy Systems. "New European Record Efficiency For Solar Cells Achieved: 39.7%." ScienceDaily. ScienceDaily, 25 September 2008. <www.sciencedaily.com/releases/2008/09/080924085202.htm>.
Fraunhofer Institute for Solar Energy Systems. (2008, September 25). New European Record Efficiency For Solar Cells Achieved: 39.7%. ScienceDaily. Retrieved December 20, 2014 from www.sciencedaily.com/releases/2008/09/080924085202.htm
Fraunhofer Institute for Solar Energy Systems. "New European Record Efficiency For Solar Cells Achieved: 39.7%." ScienceDaily. www.sciencedaily.com/releases/2008/09/080924085202.htm (accessed December 20, 2014).

Share This


More From ScienceDaily



More Matter & Energy News

Saturday, December 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Building Google Into Cars

Building Google Into Cars

Reuters - Business Video Online (Dec. 19, 2014) — Google's next Android version could become the standard that'll power your vehicle's entertainment and navigation features, Reuters has learned. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
AP Review: Nikon D750 and GoPro Hero 4

AP Review: Nikon D750 and GoPro Hero 4

AP (Dec. 19, 2014) — What to buy an experienced photographer or video shooter? There is some strong gear on the market from Nikon and GoPro. The AP's Ron Harris takes a closer look. (Dec. 19) Video provided by AP
Powered by NewsLook.com
Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Double-Amputee Becomes First To Move Two Prosthetic Arms With His Mind

Buzz60 (Dec. 19, 2014) — A double-amputee makes history by becoming the first person to wear and operate two prosthetic arms using only his mind. Jen Markham has the story. Video provided by Buzz60
Powered by NewsLook.com
Navy Unveils Robot Fish

Navy Unveils Robot Fish

Reuters - Light News Video Online (Dec. 18, 2014) — The U.S. Navy unveils an underwater device that mimics the movement of a fish. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
 
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:  

Breaking News:

Strange & Offbeat Stories

 

Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:  

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile iPhone Android Web
Follow Facebook Twitter Google+
Subscribe RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins