Stacking the deck

SUNLIGHT is free, but that is no reason to waste it. Yet even the best silicon solar cells—by far the most common sort—convert only a quarter of the light that falls on them. Silicon has the merit of being cheap: manufacturing improvements have brought its price to a point where it is snapping at the heels of fossil fuels. But many scientists would like to replace it with something fundamentally better. John Rogers, of the University of Illinois, Urbana-Champaign, is one. The cells he has devised (and which are being made, packaged into panels and deployed in pilot projects by Semprius, a firm based in North Carolina) are indeed better. By themselves, he told this year’s meeting of the American Association for the Advancement of Science, they convert 42.5% of sunlight. Even when surrounded by the paraphernalia of a panel they manage 35%. Suitably tweaked, Dr Rogers reckons, their efficiency could rise to 50%. Their secret is that they are actually not one cell, but four, stacked one on top of another. Solar cells are made of semiconductors, and every type of semiconductor has a property called a band gap that is different from that of other semiconductors. The band gap defines the longest wavelength of light a semiconductor can absorb (it is transparent to longer wavelengths). It also fixes the maximum amount of energy that can be captured from photons of shorter wavelength. The result is that long-wavelength photons are lost and short-wave ones incompletely utilised.   Cont'd

U.S.A. Pavilion at Tokyo Fuel Cell Show Highlights Strong U.S. Industry

U.S. Companies Showcase Products at Fuel Cell Expo in Japan

Valmet and Zilkha Biomass Energy announce collaborative agreement

Zilkha Biomass Energy LLC and Valmet have signed a five-year collaboration agreement in the field of steam exploded black pellets. The purpose of the agreement is to bring steam exploded black pellets to the market.

Agreement Signed Between Global Clean Energy, Inc. and Fortune 500 Industry Leader

About Sonoco Founded in 1899, Sonoco is a global provider of a variety of consumer packaging, industrial products, protective packaging, and displays and packaging supply chain services. With annualized net sales of approximately $4.8 billion, the Company has more than 19,900 employees working in 34

Solartroniks - Innovative Solutions in Solar and Engineering

Website blogging and linking Solar related news in India for the benefit of Worldwide Solar Community


Daetwyler Clean Energy (DCE) announces improvements to of their Modu-Rack™ ground mount PV racking system.

Major Investors Join Over 180 Wind Energy Stakeholders at Dallas 2014

As major investors like Goldman Sachs invest sums of up to $40billion in renewables, it is critical that an effective asset management and data analysis strategy is implemented to ensure ROI.

Power Module Design for an Ultra Efficient Three-Level Utility Grid Solar Inverter

Modules addressing the next generation solar inverter designs

Summit in Qatar to discuss best practices to arrest corrosion

Maintenance is a key factor in averting industrial breakdowns. Corrosion Management Summit will discuss best practices for structure protection.

New Man Hoisted on Board for Gaia-Wind

Leading UK small wind turbine manufacturer Gaia-Wind Ltd, today announced the appointment of Sales & Marketing Director John Gallacher to the Board of Gaia-Wind as Director.

Welcome to PV Guangzhou 2014

The 6th Guangzhou International Solar Photovoltaic Exhibition will be held in China Import & Export Fair Pazhou Complex from August 26th to 28th, 2014.

SolarEdge Launches Extended Range of Inverters

The new extended power range line of single phase inverters is here and we are taking orders!

Global Geothermal Leaders to Convene in Washington on Earth Day 2014

Earth Day, April 22

Vestas Chooses Sigmetrix, LLC for Tolerance Analysis Solution

Leader in Wind Technology Employs CETOL 6 Sigma Solution for Enhanced Robust Design and Quality Production

TPI & Gamesa Sign Long-Term Supply Agreement

TPI Composites announced today that it has signed a long-term agreement with Gamesa to supply blades for its G114 wind turbine from TPI's factory in Juarez, Mexico.

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Solar & Wind - Featured Product

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