高速路上的免費(fèi)電力？中國(guó)試鋪太陽(yáng)能公路

JINAN, China — On a smoggy afternoon, huge log carriers and oil tankers thundered down a highway and hurtled around a curve at the bottom of a hill. Only a single, unreinforced guardrail stood between the traffic and a ravine.

中國(guó)濟(jì)南——一個(gè)霧霾天的下午，運(yùn)輸木材的大貨車和油罐車沿高速公路隆隆行駛，從一處山腳下的彎道呼嘯而過(guò)。車流和一旁的山溝之間，只隔著一道沒(méi)有加固的護(hù)欄。

The route could make for tough driving under any conditions. But experts are watching it for one feature in particular: The highway curve is paved with solar panels.

在任何天氣情況下這段路都不好開(kāi)。但專家們正在監(jiān)測(cè)的是路面的一個(gè)具體部位：高速公路的彎道上鋪設(shè)了太陽(yáng)能電池板。

“If it can pass this test, it can fit all conditions,” said Li Wu, the chairman of Shandong Pavenergy, the company that made the plastic-covered solar panels that carpet the road. If his product fares well, it could have a major impact on the renewable energy sector, and on the driving experience, too.

“如果能通過(guò)這個(gè)路段的測(cè)試，就能適應(yīng)各種條件，”山東光實(shí)能源有限公司董事長(zhǎng)李武說(shuō)，鋪在路面上的那些覆蓋塑料表層的太陽(yáng)能板，就是這家公司生產(chǎn)的。如果他的產(chǎn)品運(yùn)行良好，將對(duì)可再生能源領(lǐng)域產(chǎn)生重大影響，也會(huì)極大地影響駕駛體驗(yàn)。

The experiment is the latest sign of China’s desire to innovate in, and dominate, the increasingly lucrative and strategically important market for renewable energy. The country already produces three-quarters of the solar panels sold globally, and its wind-turbine manufacturing industry is also among the world’s largest.

可再生能源市場(chǎng)越來(lái)越有利可圖，在戰(zhàn)略上也日益重要，中國(guó)渴望該領(lǐng)域的創(chuàng)新和主導(dǎo)地位，高速公路上的試驗(yàn)就是這種渴望的又一表現(xiàn)。中國(guó)已經(jīng)生產(chǎn)了全球銷售的太陽(yáng)能電池板的四分之三，其風(fēng)力發(fā)電機(jī)制造業(yè)也是世界最大的。

The potential appeal of solar roads — modified solar panels that are installed in place of asphalt — is clear. Generating electricity from highways and streets, rather than in fields and deserts packed with solar panels, could conserve a lot of land. Those advantages are particularly important in a place like China, a heavily populated country where demand for energy has risen rapidly.

這種用改裝太陽(yáng)能電池板取代瀝青鋪在路面的太陽(yáng)能公路，潛在吸引力是顯而易見(jiàn)的。在高速公路和街道上發(fā)電，而不是鋪滿太陽(yáng)能電池板的田野和沙漠，可以節(jié)約大量土地。在中國(guó)這個(gè)人口眾多、能源需求迅速增長(zhǎng)的國(guó)家，這些優(yōu)勢(shì)尤為重要。

Because roads run through and around cities, the electricity could be used practically next door to where it is generated. That means virtually no power would be lost in transmission, as can happen with projects in outlying locations. And the land is essentially free, because roads are needed anyway. Roads must be resurfaced every few years at great cost, so the installation of durable solar panels could reduce the price of maintenance.

因?yàn)槌鞘袃?nèi)部和周邊都有路，路上發(fā)的電能夠就近使用。也就是說(shuō)幾乎不會(huì)有傳輸損耗，不像那些地處偏遠(yuǎn)的太陽(yáng)能發(fā)電項(xiàng)目。而且用地基本免費(fèi)，因?yàn)楣贩凑偸切枰?。公路每隔幾年必須重鋪路面，花費(fèi)不菲，安裝耐用的太陽(yáng)能電池板也許還能降低公路維護(hù)成本。

Solar roads could also change the driving experience. Electric heating strips can melt snow that falls on them. Light-emitting diodes embedded in the surface can provide illuminated signage to direct drivers to exits and alert them to construction and other traffic hazards.

太陽(yáng)能公路也可能改變駕駛體驗(yàn)。電熱條可以融化落在路面的雪。嵌在電池板表面的發(fā)光二極管可以顯示發(fā)光標(biāo)識(shí)，指導(dǎo)駕駛員駛下出口，提醒他們注意道路施工和其他交通危險(xiǎn)。

Now, such roads are finally becoming viable. Prices have fallen drastically in recent years — thanks in large part to soaring Chinese production, a solar panel costs a tenth of what it did a decade ago. Road builders in China even want to design solar roads that can wirelessly recharge electric cars running on them, emulating a recent American experiment.

現(xiàn)在這種公路終于切實(shí)可行了。近年來(lái)太陽(yáng)能電池板的價(jià)格急劇下跌——主要?dú)w功于中國(guó)電池板的產(chǎn)量飆升，一塊電池板的價(jià)錢僅為十年前的十分之一。中國(guó)的筑路企業(yè)甚至希望趕超美國(guó)最近進(jìn)行的一項(xiàng)實(shí)驗(yàn)，設(shè)計(jì)出一種太陽(yáng)能公路，能給路上行駛的電動(dòng)汽車無(wú)線充電。

China’s leaders in solar road development are Pavenergy and Qilu Transportation. The two companies are working together here in Jinan, in Shandong Province, with Pavenergy making panels for Qilu, a large, state-owned highway construction and management company that operates the highway.

光實(shí)能源和齊魯交通發(fā)展集團(tuán)是中國(guó)太陽(yáng)能公路發(fā)展的領(lǐng)先者。兩家公司正在山東濟(jì)南進(jìn)行合作，光實(shí)能源為齊魯交通這家大型國(guó)有高速公路建設(shè)及管理公司生產(chǎn)太陽(yáng)能電池板。

The surface of these panels, made of a complex polymer that resembles plastic, has slightly more friction than a conventional road surface, according to Zhang Hongchao, an engineering professor at Tongji University in Shanghai. Professor Zhang, who helped develop Pavenergy’s road surface, said that the friction could be adjusted as needed during the manufacturing process to ensure a level of tire grip equal to that of asphalt.

上海同濟(jì)大學(xué)的交通運(yùn)輸工程學(xué)教授張宏超表示，太陽(yáng)能電池板由類似塑料的復(fù)雜聚合物制成，表面摩擦力比傳統(tǒng)路面略高。參與了光實(shí)能源電池板路面開(kāi)發(fā)的張宏超說(shuō)，制造過(guò)程中可以按需要調(diào)整表面摩擦力，確保這種路面的輪胎抓地力水平與瀝青路面相同。

The location of the solar road here, on a long curve at the bottom of a hill, was not Pavenergy’s first choice. The site was chosen because of its proximity to an electricity substation, ensuring that it would be connected to the grid. China is adding solar and wind energy sites so fast across the country that power generation projects farther from substations sometimes face delays of years in getting connected.

進(jìn)行試驗(yàn)的這條太陽(yáng)能公路位于山腳下的一處長(zhǎng)彎道，這并非光實(shí)公司的首選地點(diǎn)。選址于此是因?yàn)檫@里靠近一個(gè)變電站，確保了發(fā)電能夠入網(wǎng)。中國(guó)正在全國(guó)各地新建太陽(yáng)能和風(fēng)能發(fā)電站，速度太快，以至一些遠(yuǎn)離變電站的發(fā)電項(xiàng)目有時(shí)需要推遲數(shù)年才能入網(wǎng)。

The main Western rival to Pavenergy and Qilu is Colas, a French road-building giant that has developed 25 experimental solar roads and parking lots, mostly in France but also in Canada, Japan and the United States. The biggest of Colas’s solar sites, a country road in Normandy that opened a year and a half ago, has only half the surface area of the new solar highway in Jinan. Colas has been leery of putting solar panels on high-speed roads like the Chinese highway because of safety concerns; Professor Zhang said the panels were completely safe.

光實(shí)能源和齊魯交通主要的西方競(jìng)爭(zhēng)對(duì)手是科拉(Colas)，這家法國(guó)公路建設(shè)巨頭已經(jīng)開(kāi)發(fā)了25處實(shí)驗(yàn)性的太陽(yáng)能公路及停車場(chǎng)，主要在法國(guó)，在加拿大、日本和美國(guó)也有。科拉最大的太陽(yáng)能項(xiàng)目是一年半前在諾曼底投入使用的一條鄉(xiāng)村公路，表面積只有濟(jì)南新建太陽(yáng)能公路的一半。出于安全顧慮，科拉一直不愿將太陽(yáng)能電池板裝在與中國(guó)這條公路類似的高速路上;張宏超說(shuō)這些電池板非常安全。

Still, a litany of outstanding challenges means the wide deployment of solar roads is a long way off.

不過(guò)，一連串的難題表明太陽(yáng)能公路距離大范圍鋪設(shè)還很遙遠(yuǎn)。

For one, they are less efficient than rooftop solar panels at converting the sun’s light into electricity. They lie flat, and are intermittently covered by vehicles, so solar panels on a road produce only around half the power that rooftop ones tilted toward the sun do.

首先，太陽(yáng)能公路將陽(yáng)光轉(zhuǎn)換為電力的效率低于屋頂太陽(yáng)能電池板。公路電池板是水平放置的，而且間歇性地被車輛遮擋，而屋頂電池板向太陽(yáng)傾斜，因此前者生產(chǎn)的電能只有后者的大約一半。

Solar roads are also more expensive than asphalt. It costs about $120 a square meter, or about $11 a square foot, to resurface and repair an asphalt road each decade. By comparison, Pavenergy and Colas hope to be able to bring the cost of a solar road to $310 to $460 a square meter with mass production.

太陽(yáng)能公路也比瀝青路貴。每十年重新鋪設(shè)和修復(fù)瀝青路面，每平方米大約要花120美元。相比之下，光實(shí)能源和科拉期望在大規(guī)模生產(chǎn)時(shí)能把太陽(yáng)能公路的成本拉低到每平方米310到460美元。

Panels on a highway would likely need to be replaced less often than asphalt, Professor Zhang said. And a solar road can produce about $15 a year worth of electricity from each square meter of solar panels. So it could roughly pay for itself, compared with asphalt, over about 15 years.

張宏超說(shuō)，高速公路上的電池板的更換，可能不像瀝青路面那么頻繁。路上的電池板每平方米每年還能生產(chǎn)價(jià)值約15美元的電力。因此與瀝青相比，電池板用上大約15年就能夠抵銷成本。

Less clear is whether the panels would be able to take the pounding of millions of tires each year for more than a decade, or whether they might be stolen.

但這些電池板能否承受連續(xù)十幾年、每年幾百萬(wàn)次的車輪碾壓，或者是否會(huì)被偷走，就不那么好說(shuō)了。

Several square feet of solar panels disappeared less than a week after they were installed here in late December, raising worries of theft or even industrial espionage.

濟(jì)南這條公路上的電池板在去年12月下旬安裝完后不到一周，就不見(jiàn)了幾個(gè)平方英尺，人們擔(dān)心這是小偷甚至產(chǎn)業(yè)間諜干的。

Local police officers, facing criticism for not providing better security, said that the panels must have been crushed into tiny pieces and scattered by heavy trucks. Pavenergy declined to comment.

面對(duì)治安不力的指責(zé)，當(dāng)?shù)鼐奖硎?，電池板?yīng)該是被重型卡車壓成碎粒，碾得四散了。光實(shí)能源對(duì)此未予置評(píng)。

In the United States, installing solar roads is more complicated.

在美國(guó)，鋪設(shè)太陽(yáng)能公路就是一個(gè)更棘手的問(wèn)題了。

With the exception of some bridges and sections of interstate highways, American roads tend to be built with a lot of asphalt, but with less concrete underneath than roads elsewhere, said Kara M. Kockelman, a transportation engineering professor at the University of Texas.

德克薩斯州大學(xué)交通工程教授卡拉·M·科克曼(Kara M. Kockelman)說(shuō)，除了部分橋梁和州際高速公路的某些路段外，美國(guó)公路往往用大量瀝青鋪就，但路面下的混凝土比其他地方的公路用得少。

The problem with asphalt is that it compresses slightly under the weight of trucks. The blue silicon of solar cells, the panels’ electricity-generating component, can withstand being mashed by many tons of weight. But the nearly paper-thin cells snap when bent, like a thin sheet of sugar. (This is not as much of an issue in China, where highways are built with very thick concrete bases.)

瀝青的問(wèn)題是在卡車的重壓下會(huì)輕微變形。太陽(yáng)能電池的藍(lán)色硅晶片，也就是電池板的發(fā)電部件，能夠承受數(shù)噸的重壓。但一遇彎折，紙一般薄的硅晶片就會(huì)像薄薄的糖片一樣折斷。(在中國(guó)，高速公路鋪有很厚的混凝土路基，這就不是太大的問(wèn)題。)

Still, executives here are hopeful. They say that the technology is ready and that they are not concerned even by the complications of American highway construction.

不過(guò)這里的企業(yè)高管們是滿懷希望的。他們說(shuō)技術(shù)已然完備，即使美國(guó)高速公路建設(shè)的情況復(fù)雜，他們也并不擔(dān)心。

“If conditions permit,” Xu Chunfu, Qilu’s chairman, said, “I would like to build a solar road in the United States.”

“如果條件允許，”齊魯交通發(fā)展集團(tuán)的董事長(zhǎng)徐春福說(shuō)，“我還想到美國(guó)建一條光伏路。”