Navigation Links
Evolution inspires more efficient solar cell design
Date:1/25/2013

The sun's energy is virtually limitless, but harnessing its electricity with today's single-crystal silicon solar cells is extremely expensive 10 times pricier than coal, according to some estimates. Organic solar cells polymer solar cells that use organic materials to absorb light and convert it into electricity could be a solution, but current designs suffer because polymers have less-than-optimal electrical properties.

Researchers at Northwestern University have now developed a new design for organic solar cells that could lead to more efficient, less expensive solar power. Instead of attempting to increase efficiency by altering the thickness of the solar cell's polymer layer a tactic that has preciously garnered mixed results the researchers sought to design the geometric pattern of the scattering layer to maximize the amount of time light remained trapped within the cell.

Using a mathematical search algorithm based on natural evolution, the researchers pinpointed a specific geometrical pattern that is optimal for capturing and holding light in thin-cell organic solar cells.

The resulting design exhibited a three-fold increase over the Yablonovitch Limit, a thermodynamic limit developed in the 1980s that statistically describes how long a photon can be trapped in a semiconductor.

A paper about the results, "Highly Efficient Light-Trapping Structure Design Inspired by Natural Evolution," was published January 3 in Scientific Reports, a publication of Nature.

In the newly designed organic solar cell, light first enters a 100-nanometer-thick "scattering layer," a geometrically-patterned dielectric layer designed to maximize the amount of light transmitted into the cell. The light is then transmitted to the active layer, where it is converted into electricity.

"We wanted to determine the geometry for the scattering layer that would give us optimal performance," said Cheng Sun, assistant professor of mechanical engineering in Northwestern's McCormick School of Engineering and Applied Science and co-author of the paper. "But with so many possibilities, it's difficult to know where to start, so we looked to laws of natural selection to guide us."

The researchers employed a genetic algorithm, a search process that mimics the process of natural evolution, explained Wei Chen, Wilson-Cook Professor in Engineering Design and professor of mechanical engineering at McCormick and co-investigator of the research.

"Due to the highly nonlinear and irregular behavior of the system, you must use an intelligent approach to find the optimal solution," Chen said. "Our approach is based on the biologically evolutionary process of survival of the fittest."

The researchers began with dozens of random design elements, then "mated" and analyzed their offspring to determine their particular light-trapping performance. This process was carried out over more than 20 generations and also accounted for evolutionary principles of crossover and genetic mutation.

The resulting pattern will be fabricated with partners at Argonne National Laboratory.


'/>"/>

Contact: Megan Fellman
fellman@northwestern.edu
847-491-3115
Northwestern University
Source:Eurekalert

Related biology technology :

1. Brain State Technologies to Host Open House and Demonstrate Their Revolutionary Technology
2. Crisalix Awarded as a Leading Life Science Company that is Revolutionizing the Medical Industry
3. Research discovery could revolutionize semiconductor manufacture
4. Spanish scientists design a revolutionary data storage device
5. Revolutionary Tetrapod Quantum Dot Synthesis US Patent Granted
6. New UCLA Engineering research center to revolutionize nanoscale electromagnetic devices
7. Researchers peek at the early evolution of sex chromosomes
8. Discovered Evolution of Genomic Sequences -- from Ocean Archaea to Brain Cancer -- Leads to New Synthetic Replikin Vaccines for Infectious Diseases and Cancer
9. Evolution Issue of the Month 2. Natural Selection--Not the Best Idea Anyone Ever Had
10. Martha Stewart Reveals the Secret Behind her Radiant Skin is Revolutionary Anti-aging BIOEFFECT EGF SERUM
11. New Revolutionary Femoral Access Site Closure Device Shows Unparalleled Efficacy, Safety & Ease of Use, in a Wide Range of Patients Including Patients With a Challenging Anatomy
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/27/2016)... NC (PRWEB) , ... June 27, 2016 , ... ... mission to bring innovative medical technologies, services and solutions to the healthcare market. ... and implementation of various distribution, manufacturing, sales and marketing strategies that are necessary ...
(Date:6/27/2016)... , June 27, 2016  Liquid Biotech ... the funding of a Sponsored Research Agreement with ... tumor cells (CTCs) from cancer patients.  The funding ... CTC levels correlate with clinical outcomes in cancer ... data will then be employed to support the ...
(Date:6/24/2016)... , June 24, 2016  Regular discussions on a range ... place between the two entities said Poloz. Speaking ... Ottawa , he pointed to the country,s inflation ... federal government. "In ... "Both institutions have common economic goals, why not sit down ...
(Date:6/24/2016)... ... June 24, 2016 , ... While the majority of commercial spectrophotometers and ... and the 6000i models are higher end machines that use the more unconventional z-dimension ... light beam from the bottom of the cuvette holder. , FireflySci has developed ...
Breaking Biology Technology:
(Date:6/22/2016)... 2016 On Monday, the Department of Homeland ... share solutions for the Biometric Exit Program. The Request ... Protection (CBP), explains that CBP intends to add biometrics ... the United States , in order to deter ... Logo - http://photos.prnewswire.com/prnh/20160622/382209LOGO ...
(Date:6/9/2016)... in attendance control systems is proud to announce the introduction of fingerprint attendance control ... right employees are actually signing in, and to even control the opening of doors. ... ... ... Photo - ...
(Date:6/2/2016)... , June 2, 2016   The Weather Company ... announcing Watson Ads, an industry-first capability in which consumers will ... being able to ask questions via voice or text and ... Marketers have long sought an ... consumer, that can be personal, relevant and valuable; and can ...
Breaking Biology News(10 mins):