By mid-century, the sun could be the largest source of energy and help reign¹ in global warming by preventing the release of billions of tons of carbon dioxide emissions², according to a new report from the International Energy Agency.

国际能源署（International Energy Agency）在最近发布的一份报告中表示，到本世纪中叶，太阳能有可能成为全球使用规模最大的能源，这将会减少数十亿吨二氧化碳的排放，从而有助于抑制全球变暖趋势。

The bullish report is the latest dose of good news for the solar industry that has seen phenomenal growth. Global demand is expected to double every two years through 2022 as prices fall and the technology continues to improve. The United States is one of the markets poised³ for strong growth.

对于近年增长势头迅猛的太阳能行业而言，这份乐观的报告无疑是一针强心剂。从现在起直到2022年，随着太阳能的价格逐步下降而技术持续完善，预期全球需求将会每两年翻上一番。美国市场更是有望出现强劲增长的市场之一。

Though it is the fastest growing source of renewable electricity, solar power still only represents a fraction of energy mix dominated by fossil fuels. Globally, it provides 0.5 percent of electricity generation and, in the United States, it currently provides 0.2 percent of energy generation.

虽然太阳能是增长最快的可再生电力来源，但在以矿物燃料为主的能源组合中，太阳能目前仍然只占很小的比例。从全球来看，太阳能发电仅占各类能源总发电量的0.5%，而在美国，这一比例仅为0.2%。

“The rapid cost decrease of photovoltaic modules⁴ and systems in the last few years has opened new perspectives for using solar energy as a major source of electricity in the coming years and decades,” IEA Executive Director Maria van der Hoeven said. “However, both technologies are very capital intensive: almost all expenditures⁵ are made upfront. Lowering the cost of capital is thus of primary importance for achieving the vision in these roadmaps.”

“过去几年里，光伏组件和光伏系统的成本迅速下降，为太阳能在未来数年和数十年内发展成为主要的电力来源开辟了新的前景，”国际能源署总干事玛丽亚o范德胡芬表示，“但是，这两种技术都属于资本密集型行业——几乎所有的开支都需要在前期就早早投入。因此降低资本成本便成了实现这些发展路径图的首要任务。”

The price of solar photovoltaic, or PV, systems is expected to drop by 65 percent by 2050, van der Hoeven said. Another key to the growth of solar will be government offering up clear policies to support the sector⁶. The solar sector in the United States, for example, has benefited from the solar investment tax credit, which provides a 30 percent tax credit for solar systems on residential⁷ and commercial properties. The industry is pushing for it to be extended beyond 2016.

据范德胡芬介绍，到2050年，预计太阳能光伏（PV）系统的价格将下降65%。而推动太阳能增长的另外一个关键所在，则要靠政府制定出明确的产业扶持政策。例如美国的太阳能产业就可以获得太阳能投资税收减免优惠——政府对民用住宅和商用建筑中采用的太阳能发电系统提供高达30%的税收减免。该行业目前正在积极游说政府将这一优惠延长到2016年以后。

“By contrast,” van der Hoeven said, “where there is a record of policy incoherence, confusing signals or stop-and-go policy cycles, investors⁸ end up paying more for their investment, consumers pays more for their energy, and some projects that are needed simply will not go ahead.”

“与之相反，”范德胡芬继续介绍，“有些地方的政策不连贯、不明朗或者时断时续，导致投资者需要为投资付出更高的成本，消费者需要为购买能源付出更高的费用，甚至有一些存在需求的项目最后却难以为继。”

With 137 gigawatts of installed capacity at the end of 2013, PV has dominated the market — adding more capacity since 2010 than the previous four decades — and will continue to do so through 2030, according to the IEA. But once solar reaches from 5 percent to 15 percent of electricity generation, the picture changes.

根据国际能源署的报告，太阳能光伏在2013年年底的装机容量达到137千兆瓦，在能源市场上占据了主导地位——自2010年至今的新增容量甚至超过了之前40年的新增容量——并会将这种增长势头一直延续到2030年。不过，一旦太阳能光伏占到了各类能源总发电量的5%到15%，局面就会发生变化。

At that point, PV begins to lose value in wholesale⁹ markets while solar thermal¹⁰ electricity, which uses the solar to produce steam power, “takes off at this stage thanks to (concentrating solar power) plants’ built-in thermal storage, which allows for generation of electricity when demand peaks in late afternoon and in the evening, thus complementing¹¹ PV generation.”

到那时，太阳能光伏发电将会开始在批发市场丧失价值，而利用太阳能产生蒸汽动力的太阳能热能发电技术，则会“在这一阶段开始蓬勃发展，这要归功于（聚光太阳能）电厂内部的蓄热器可在属于用电高峰时段的傍晚和夜间进行热能发电，对太阳能光伏发电形成补充。”

Across the globe, China is expected to continue to lead the way on PV, followed by the United States. Solar thermal, meanwhile, has greatest potential in sunny areas meaning it probably be a “major opportunity” for Africa, India, the Middle East and the United States.

展望全球，预计中国将继续在太阳能光伏领域引领风骚，美国则紧随其后。与此同时，太阳能热能发电则在日照充足的地区拥有无限的潜力，这意味着非洲、印度、中东和美国将迎来“重大发展机遇”。