Wednesday, October 17, 2012

IBM sets world record for photovoltaic energy conversion efficiency

IBM's CZTS Solar Cell Device (Credit: IBM Research)
An efficient and affordable photovoltaic (PV) solar cell made of readily available natural materials was developed by team comprising IBM’s Materials Science and Japanese  company, Solar Frontier.

“Tests of our Cu2ZnSn(S,Se)4 (made of readily available copper, zinc, and tin, and referred to as CZTS) thin-film devices have achieved a world-record PV solar-to-electric power conversion efficiency of 11.1% (10% better than any previous reports) for this class of semiconductors, say IBM Research photovoltaic scientists Teodor Todorov and David Mitzi. And it can be manufactured by simple ink-based techniques such as printing or casting.

What makes CZTS better

Energy from the sun reaching the earth’s surface amounts to several thousand times our global consumption of electricity. Yet electricity from photovoltaic (PV) solar cells currently contributes significantly less than one percent of worldwide production. Of the numerous existing PV technologies, none so far have combined the virtues of being highly efficient, cheaply scalable and made with abundantly available materials.

Currently, the most widespread PV semiconductors, made of crystalline silicon, are abundant and highly efficient. They’re in panels used for everything from home electricity to the International Space Station. However, they have extremely high material purity requirements (>99.9999%), and the wafers are typically cut from large solid ingots and wired in series to form PV modules — making it expensive and difficult to upscale.

Other thin-film chalcogenide materials used in PV cells, such as Cu(In,Ga)(SSe)2 (CIGS) and CdTe, have been developed to a performance level close to that of silicon, with inherently more scalable processing, the scientists say. They are directly deposited on large-area, low-cost substrates such as glass, metal or plastic foil.

But their compounds contain rare and expensive elements that increase cost and limit their manufacturing levels to less than 100GW per year (worldwide continuous electricity consumption is 15 Terawatts — 150 times greater than the level of what these CIGS can produce).

“Our CZTS PV cells could potentially yield up to 500 GW per year — getting closer to the Terawatt levels of renewable electricity the planet needs.”

They hope that within several years this new class of photovoltaic materials will begin to contribute to the wider availability of lower-cost solar electricity.

CIGS     - Cu(In,Ga)(SSe)2 (thin-film material)
CZTS     - Cu2ZnSn(S,Se)4  (made of copper, zinc, and tin)
GW       - gigawatt
PV        - photovoltaic

Note: The original report was written by Teodor Todorov and David Mitzi, IBM Research photovoltaic scientists. Reference: IBM Research

TheGreenMechanics: Moving ahead for the better. With more and more breakthrough on finding cheaper and more efficient solar cell, let's hope that we wouldn't have to resort to nuclear power in the distant future.


tehr said...

makin lama teknologi makin maju
tak sabar pula rasanya nak tunggu dapat bekalan tenaga murah ni

de engineur said...

Akan ambil sedikit masa untuk mempraktikkannya dalam aplikasi