VOA标准英语2010年-New Way of Making Solar Cells Promises

New design produces flexible panels using only 1-2 percent as much silicon¹

Art Chimes | Washington, DC 19 February 2010

"You can use 100 times less silicon. And that's potentially very significant." – Harry² Atwater

Schematic diagram of the light-trapping elements used to optimize³ absorption within a polymer-embedded⁴ silicon wire array

A new way of making solar cells promises a cheaper way to generate electricity from the sun and new ways to integrate solar power into other products.

Solar cells, or photovoltaics, are widely made using wafers of silicon that are stiff and brittle⁵. California Institute of Technology physics professor Harry Atwater is making photovoltaics differently.

"Our technology uses 50-100 times less silicon," he said, "in the form of a sparse⁶ array of wires. And that sparse array of wires has exactly the same light absorption and electricity-collection properties as the conventional silicon wafer cell."

Photomicrograph of a silicon wire array embedded within a transparent⁷, flexible polymer film

The tiny silicon wires stick up from the base, or substrate, looking something like a microscopic⁸ hair brush. And because the key component⁹ of solar cells is an expensive, highly purified form of silicon, there's a real economic benefit to this design.

"So what that means is, in terms of cost, is you can use 100 times less silicon. And that's potentially very significant."

But the silicon is what converts light into electricity, so you might think using so much less silicon would reduce the electrical output, but Atwater says that's not the case.

"The light comes in and is both directly absorbed by the wires, and some of the light bounces around in between the wires. And that bouncing around or multiple scattering¹⁰ in between the wires results in dramatically enhanced absorption," Atwater explained. "In fact, the absorption enhancement that we see is in the range of 20 to 50 times the single-pass absorbance."

Atwater and his colleagues have made prototypes of the design in the lab, and the product doesn't look like the typical solar panels you might see on top of a building.

"What we do with our wire arrays is grow them on a supporting substrate, and we peel them off inside a plastic sheet, so that the material has exactly the optical and electrical properties of a silicon wafer, but instead it basically has the mechanical properties of a flexible plastic sheet."

That flexibility¹¹ opens the door to potential new applications, such as what Atwater calls "integrated photovoltaics." For example, the solar cell could be built into roofing material, saving money on installation. Other ideas for new uses come from the physical form of Atwater's novel design.

"Well, one of the things that's interesting about these flexible sheets is that they can be curved, so you could imagine putting them in unconventional forms, like on the surface of a vehicle or something like that, where you don't have a flat surface."

The Caltech professor says he's optimistic about commercializing his new solar cell design because the manufacturing process should not require development of any new technologies. And he stresses that it should reduce the cost of generating power from the sun.

"The wonderful thing about solar energy is that it's accessible and available everywhere in the world, from the cloudiest place in northern Europe to the sunniest place in north-central Africa to the Outback of Australia to South Asia. And in fact [the use of solar energy is] growing worldwide for that reason."

Harry Atwater's description of his new design for solar cells is published in the journal Nature Materials.
 

1 silicon   

n.硅(旧名矽)

参考例句：

• This company pioneered the use of silicon chip.这家公司开创了使用硅片的方法。
• A chip is a piece of silicon about the size of a postage stamp.芯片就是一枚邮票大小的硅片。

2 harry   

vt.掠夺，蹂躏，使苦恼

参考例句：

• Today,people feel more hurried and harried.今天，人们感到更加忙碌和苦恼。
• Obama harried business by Healthcare Reform plan.奥巴马用医改掠夺了商界。

3 optimize   

v.使优化 [=optimise]

参考例句：

• We should optimize the composition of the Standing Committees.优化人大常委会组成人员的结构。
• We should optimize our import mix and focus on bringing in advanced technology and key equipment.优化进口结构，着重引进先进技术和关键设备。

4 embedded   

a.扎牢的

参考例句：

• an operation to remove glass that was embedded in his leg 取出扎入他腿部玻璃的手术
• He has embedded his name in the minds of millions of people. 他的名字铭刻在数百万人民心中。

5 brittle   

adj.易碎的；脆弱的；冷淡的；(声音)尖利的

参考例句：

• The pond was covered in a brittle layer of ice.池塘覆盖了一层易碎的冰。
• She gave a brittle laugh.她冷淡地笑了笑。

6 sparse   

adj.稀疏的，稀稀落落的，薄的

参考例句：

• The teacher's house is in the suburb where the houses are sparse.老师的家在郊区，那里稀稀拉拉有几处房子。
• The sparse vegetation will only feed a small population of animals.稀疏的植物只够喂养少量的动物。

7 transparent   

adj.明显的，无疑的；透明的

参考例句：

• The water is so transparent that we can see the fishes swimming.水清澈透明，可以看到鱼儿游来游去。
• The window glass is transparent.窗玻璃是透明的。

8 microscopic   

adj.微小的，细微的，极小的，显微的

参考例句：

• It's impossible to read his microscopic handwriting.不可能看清他那极小的书写字迹。
• A plant's lungs are the microscopic pores in its leaves.植物的肺就是其叶片上微细的气孔。

9 component   

n.组成部分，成分，元件；adj.组成的，合成的

参考例句：

• Each component is carefully checked before assembly.每个零件在装配前都经过仔细检查。
• Blade and handle are the component parts of a knife.刀身和刀柄是一把刀的组成部分。

10 scattering   

n.[物]散射；散乱，分散；在媒介质中的散播adj.散乱的；分散在不同范围的；广泛扩散的；（选票）数量分散的v.散射(scatter的ing形式)；散布；驱散

参考例句：

• The child felle into a rage and began scattering its toys about. 这孩子突发狂怒，把玩具扔得满地都是。 来自《简明英汉词典》
• The farmers are scattering seed. 农夫们在播种。 来自《简明英汉词典》

11 flexibility   

n.柔韧性，弹性，（光的）折射性，灵活性

参考例句：

• Her great strength lies in her flexibility.她的优势在于她灵活变通。
• The flexibility of a man's muscles will lessen as he becomes old.人老了肌肉的柔韧性将降低。