以下為理工教材原文及譯文：
+ 第十三篇 Better Solar Energy Systems: More Heat,More Light
Solar photovoltaic thermal energy systems,or PVTs, generate both heat and electricity, but until now they haven’t been very good at the heat-generating part compared to a stand-alone solar thermal collector. That’s because they operate at low temperatures to cool crystalline silicon solar cells, which lets the silicon generate more electricity but isn’ta very efficient way to gather heat.
That’s a problem of economics. Good solar hot-water systems can harvest much more energy than a solar-electric system at a substantially lower cost. And it’s also a space problem: photovoltaic cells can take up all the space on the roof, leaving little room for thermal applications.
In a pair of studies, Joshua Pearce, anassociate professor of materials science and engineering, has devised a solution in the form of a better PVT made with a different kind of silicon. His research collaborators are Kunal Girotra from Thin Silicon in California and Michael Pathak and Stephen Harrison from Queen’s University, Canada.
Most solar panels are made with crystalline silicon, but you can also make solar cells out of amorphous silicon, commonly known as thin-film silicon. They don’t create as much electricity, but they are lighter, flexible, and cheaper. And, because they require much less silicon,they have a greener footprint. Unfortunately, thin-film silicon solar cells are vulnerable to some bad-news physics in the form of the Staebler-Wronski effect.
“That means that their efficiency drops when you expose them to light— pretty much the worst possible effect for a solar cell,” Pearce explains,which is one of the reasons thin-film solar panels make up only a small fraction of the market.
However, Pearce and his team found a way to engineer around the Staebler-Wronski effect by incorporating thin-film siliconin a new type of PVT. You don’t have to cool down thin-film silicon to make it work. In fact, Pearce’s group discovered that by heating it to solar-thermal operating temperatures, near the boiling point of water, they could make thicker cells that largely overcame the Staebler-Wronski effect. When they applied the thin-film silicon directly to a solar thermal energy collector,they also found that by baking the cell once a day, they boosted the solar cell’s electrical efficiency by over 10 percent.
譯文：
第十三篇 更有效的太陽(yáng)能系統(tǒng)：更多熱量，更強(qiáng)燈光
太陽(yáng)能光伏熱能系統(tǒng)，也叫PVT，能夠生成熱量和電能。與太陽(yáng)熱能單機(jī)收集器相比，傳統(tǒng)太陽(yáng)能光伏熱能系統(tǒng)在轉(zhuǎn)換熱能方面效率不是很高。原因是，為了使晶體硅太陽(yáng)能電池冷卻，該系統(tǒng)在低溫下工作。因此，硅體能產(chǎn)出更多的電能，卻不能有效地產(chǎn)生熱量。
第一，經(jīng)濟(jì)問(wèn)題。好的太陽(yáng)能熱水系統(tǒng)比太陽(yáng)能電力系統(tǒng)收集的能量更多，而且成本低得多。第二，空間問(wèn)題。光電管占去屋頂?shù)乃械目臻g，幾乎沒(méi)有空間留給熱能的產(chǎn)出。
在一項(xiàng)研究中，材料科學(xué)與工程副教授Joshua Pearce找到了一個(gè)解決方案：用另外一種硅制成PVT來(lái)解決效能問(wèn)題。他的合作者有：來(lái)自加利福尼亞ThinSilicon的Kunal Girotra和加拿大皇后大學(xué)的Michael Pathak和Stephen Harrison。
大部分太陽(yáng)能電池板是由晶體硅制成，但是，你也可以用非晶硅制成太陽(yáng)能電池，這種非晶體硅通常被叫作薄膜硅。它們不能產(chǎn)生那么多的電能，但是更 亮、更靈巧、成本更低。而且，由于它們需要的硅較少，它們更環(huán)保。不幸的是，薄膜硅太陽(yáng)能電池易受SWE效應(yīng)攻擊(在光的照射下，非晶硅氫的導(dǎo)電性短時(shí)間 內(nèi)顯著衰退，這種特性被稱(chēng)為SWE效應(yīng))。
“當(dāng)被暴露在光線下，那就意味著它們的能效會(huì)降低——這幾乎是太陽(yáng)能電池最可能糟糕的效應(yīng)。”Pearce解釋道。這就是薄型太陽(yáng)能板只占有一少部分市場(chǎng)的原因。
然而，Pearce和他的團(tuán)隊(duì)把薄膜硅合成為一種新型的PVT，可以克服或繞過(guò)SWE效應(yīng)。這種方法可以不用冷卻薄膜硅而讓它們產(chǎn)生效能。事實(shí) 上，Pearce團(tuán)隊(duì)發(fā)現(xiàn)，通過(guò)把薄膜硅加熱到太陽(yáng)熱能操作溫度，即臨近水的沸點(diǎn)，可以把它制成較厚的電池，從而可以遏制SWE效應(yīng)。當(dāng)把薄膜硅直接應(yīng)用 到太陽(yáng)熱能集熱器時(shí)，他們也發(fā)現(xiàn)，如果一天把太陽(yáng)能電池加熱一次，那么太陽(yáng)能的電力效能會(huì)增加10%。
