Old ideas die hard. The country has been debating renewable energy for decades -- how much we should support it, what place it should have in our energy policy, how big an impact it actually has. Yet many of the things we think we know about renewable energy go back to the earliest arguments. Many of the debating points we hear today are based on outdated facts and assumptions that don't hold up anymore. So, we set out to look at a few persistent myths or beliefs held by both supporters and critics of renewable energy. We've focused largely on wind and solar power, in part because they've shown explosive growth in recent years but also because they are at the center of political debates over energy.

旧观念难改。美国已讨论了几十年的可再生能源：我们该以多大的力度支持它；它在我们的能源策略中应该占据什么样的位置；它到底有多大的冲击力。但是，我们自以为知道的关于可再生能源的许多东西又回到了最初的论点。我们现在听到的许多论点都是基于过时的事实和假设，而这些事实和假设早就经不起推敲了。因此，现在我们打算回顾一下可再生能源的支持者和批评者都拥护的长期存在的几个谬误或者说看法。我们将主要关注风力发电和太阳能发电，部分原因是它们在近些年显现出了爆炸式的增长，同时还因为它们是有关能源的政治辩论的中心所在。

MYTH NO. 1: Renewables Are an Insignificant Source of Power

谬误1 可再生能源不过是微不足道的能量来源

One of the most persistent criticisms of renewables is that they account for a fraction of the U.S. electricity system -- despite years of federal subsidies and breakneck growth.

对于可再生能源一个最持久的批评是，尽管享受了多年的联邦政府补贴并经历了快速增长，它们却依然只占美国电力系统的一小部分。

When looking at 'newer' renewable energies such as wind and solar power, that's largely true. Wind accounts for about 5% of generation capacity and a little over 4% of U.S. electricity production, or roughly one-tenth what coal provides.

如果说的是像风能和太阳能这种“较新的”可再生能源，这种说法很大程度上是对的。风力发电仅占美国发电容量的约5%，占总发电量的4%略多一点，相当于煤炭发电量的约十分之一。

But the criticism overlooks one important point: Conventional hydroelectric power, such as the Hoover Dam, is also renewable energy. Taken together, hydroelectric and other sources -- biomass, geothermal, solar and wind -- combined to account for 12% of U.S. electricity production last year, and close to 14% so far this year. The entire nuclear fleet provides about 19%.

但是批评人士忽视了重要的一点：传统的水力发电，如胡佛水坝(Hoover Dam)，也是可再生能源。加在一起，水力发电和其它能源发电――由生物能、地热能、太阳能和风能提供的电量――占了去年美国发电量的12%，今年截至目前为止发电量的近14%。核发电量在美国总发电量中的比重大约是19%。

It's also important to remember the scale of the country's renewable efforts. The U.S. has the second-biggest electricity system in the world, accounting for about 20% of the entire world's generation capacity. Wind power's 5% of that pie is a big slice. The 60-odd gigawatts of wind power installed in the U.S. amounts to more electricity-generation capacity than in the entire country of Australia or Saudi Arabia, and as much as all of Mexico. It's about half as much power as in France or Brazil.

还有一点很重要，就是不要忘了美国可再生能源业务的规模。美国拥有全球第二大电力系统，占全球发电容量的约20%。风能所占的5%可是很大的一杯羹。美国的风电装机容量为60千兆瓦上下，比澳大利亚和沙特阿拉伯的发电容量都要多，相当于墨西哥的总发电容量以及法国和巴西发电容量的大约一半。

To be sure, the wind doesn't always blow. Wind farms produce only about one-third of their listed capacity, while a nuclear plant produces almost 100%. But even that discounted amount of electricity generated by U.S. wind farms is huge in global terms -- 54% of all the juice generated by Mexico, 26% of France and Brazil, 62% of Australia, 64% of Turkey and more than twice that of Switzerland.

当然，风也不是吹个不停。风电场生产的实际电量只有其装机总容量的约三分之一，而核电厂生产的实际电量几乎是装机总容量的100%。但就全球范围来看，美国风电场的发电量即使打了折扣，也是非常庞大的――相当于墨西哥总发电量的54%，法国和巴西的26%，澳大利亚的62%，土耳其的64%，比瑞士总发电量的两倍还要多。

The seemingly small share of power produced by renewable energy at the national level also reflects the fact that some states have a lot of green power and some have practically none. Texas has the biggest electricity system in the country, and gets 11% of its juice from renewables, nearly all from wind. New York and Georgia both have large power sectors, but get relatively small amounts from renewables.

可再生能源生产的电量在全国范围来说貌似很小，这也反映出了一个事实，那就是有些州拥有丰富的绿色能源，而有些州几乎没有。得克萨斯州有着全国最大的发电系统，其中11%是利用可再生能源发电，这些可再生能源基本全是风能。纽约州和佐治亚州的电力行业都很大，但可再生能源的发电比例就相对较校

MYTH NO. 2: Renewables Can Replace All Fossil Fuels

谬误2 可再生能源可替代全部矿物燃料

The flip side of critiques of renewable energy is boosterism. A handful of proponents describe a future where 100% of energy needs can be met affordably and reliably by renewables.

对于可再生能源的批判的另一面则是热捧。一小部分支持者描述了这样一个未来：届时，我们所需的能源可以稳定可靠地、100%地由可再生能源提供。

Focusing on electricity, researchers at the National Renewable Energy Laboratory tackled this question. They found that, technically, by 2050 the U.S. could get 80% of its electricity from renewable energy and keep the lights on every hour, every day, in every corner of the country. (Their study didn't consider a 100%-renewable scenario.)

美国国家可再生能源实验室(National Renewable Energy Laboratory)的研究人员以电为中心研究了这个问题。他们发现，从技术上来说，到2050年，美国80%的电都可来自可再生能源，并让全国每个角落在每天的每个小时都亮着灯。（他们的研究并未考虑100%的电都由可再生能源提供的情景。）

Perhaps. But getting there would be a long, tough slog. The study found that the U.S. would need to install about 20,000 megawatts of renewable generating capacity every year for a couple of decades, gradually ramping up to about 40,000 megawatts every year. The study found no reason to doubt the global renewable-energy industry's ability to eventually meet that level of production. What might be trickier, the study found, is finding a place to put all those wind farms, solar arrays and hydroelectric facilities.

这是有可能的。但实现这一目标将是步履维艰的漫漫征程。该研究发现，要实现这一目标，美国必须在20年内让可再生能源装机容量每年增加约20,000兆瓦特，然后逐步提高至每年增加约40,000兆瓦特。该研究发现，没有理由怀疑全球再生能源产业最终达到这一生产水平的能力。但有可能棘手的问题是，寻找一个地方放置所有那些风电尝太阳能电池阵和水利发电设施。

Managing the big upfront capital costs of wind and solar power would be another obstacle. And down the road there could be another challenge: Areas with lots of variable power could see wholesale power prices close to zero at times. That would complicate the economic case for fresh investments in generation capacity year after year.

管理利用风能和太阳能所需的巨额预付资本成本将成为另一块拦路石。而且将来可能还有一个挑战：拥有大量可变电源的地区，那里的批发电价有时会接近于零，这将使逐年对发电容量新增投资变得复杂。

The U.S. would also need to virtually duplicate the entire existing network of transmission lines by 2050 to handle 80% renewable energy. The study notes that the trick would be figuring out where the lines would go, who would pay for them, and which state and local governments would be in charge.

美国还需在2050年前将整个现有的输电线路网复制重建，以应对80%由再生能源生产的电能。该研究强调，其中关键在于弄清楚这些线路该怎么走，谁将为此支付费用，该由哪个州和地方政府来负责管理。

In other words, there's no technical reason renewable energy can't provide 80% of the power in the U.S. by midcentury. But there are a host of challenges that would have to be met first.

换句话说，没有任何技术原因阻止美国在本世纪中叶实现其80%的电能由再生能源提供。但首先摆在面前的便是诸多的挑战。

MYTH NO. 3: Renewables Are Too Expensive

谬误3 可再生能源太贵了

Forget about problems down the road. Another criticsm of renewables in the here and now: They're expensive ways to generate electricity.

先别管那些以后要面临的问题。此时此刻就有一个针对再生能源的批评：用它们来发电太贵了。

One new, comprehensive comparison of wholesale electricity prices, in the Journal of Environmental Studies and Sciences, concludes that coal-generated power costs 3 cents a kilowatt-hour; new gas plants would produce juice at 6.2 cents; wind power costs 8 cents; and solar photovoltaic, 13.3 cents.

《环境研究与科学杂志》(Journal of Environmental Studies and Sciences)对批发电价进行了新的全面比较，发现煤炭发电的成本为每度电三美分，新燃气发电厂的成本为每度电6.2美分，风能发电为八美分，太阳能光伏发电则为13.3美分。

But there are two big issues to bear in mind. First, costs are falling fast -- thanks largely to technological advances such as larger wind turbines and cheaper components for solar-power arrays -- so in some places, solar and wind power can cost even less.

但别忘了非常重要的两点。首先，成本下跌迅速――这很大程度上得益于技术进步，如更大型的风力涡轮机和更便宜的太阳能电池阵组件等的发明――因此在一些地方，太阳能和风能的成本有可能反而更低。

The latest price data for wind-energy power-purchase agreements, released by the Department of Energy last month, showed that nationwide, the price of wind-generated electricity fell to just over 4 cents per kilowatt-hour nationwide, not counting the 2.2-cent federal tax subsidy. In some regions, well-sited wind farms produce electricity for closer to 2 cents.

美国能源部8月份发布的风电采购协议最新价格数据显示，在全国范围内，风力发电的价格已经下降至每度电四美分多一点点，这还没算上2.2美分的联邦税收补贴。在一些地区，选址得当的风电场生产的电的价格接近二美分一度。

Likewise, Lawrence Berkeley National Laboratory just released its latest report on the costs of installing solar power. Costs for small-scale solar residential arrays fell by about 13% in the past year, driven largely by cheaper solar components due to a global supply glut. Utility-scale prices also fell.

同样，劳伦斯伯克利国家实验室(Lawrence Berkeley National Laboratory)刚刚发布的最新报道研究了安装太阳能发电装置的费用。小型家用太阳能电池阵的价格在过去一年内下降了约13%，这很大程度上是由于全球供应过剩，太阳能电池阵组件变得更加便宜造成的。用于公用事业的太阳能发电装置的价格同样有所下降。

There's also the question of hidden costs. Coal-fired electricity, for instance, has nasty side effects, including air pollution, health impacts and carbon-dioxide emissions that contribute to global warming (all of which factored into the Obama administration's proposal Friday for new limits on coal emissions) -- and those don't show up in coal's price tag. If coal and other fossil fuels had to tally the total costs their use imposed on society, coal wouldn't be the cheapest source of electricity, and clean-burning renewables wouldn't look nearly so pricey.

另一个便是隐性成本的问题。比如说，煤炭发电有着非常严重的副作用，包括空气污染、不利于健康以及导致全球升温的二氧化碳排放等等（考虑到所有这些因素，奥巴马政府在9月20日公布了二氧化碳排放标准新提案），这些都不会在煤炭的价格标签上显示出来。如果将使用煤炭和其它矿物燃料对社会带来的全部成本都计算入内，煤炭就不会是最便宜的发电原料，清洁的可再生能源也不会看起来如此昂贵了。

Add all the hidden costs together, and the total cost of different power sources looks quite different, according to that recently published study. At an existing coal-fired plant, the cost goes up by 6 cents per kilowatt-hour, making its true cost 9 cents; at a new coal plant, it would go up by about 4 cents to 13.2 cents. New natural-gas-fired electricity would go up by 1.3 cents, bringing its total to 7.5 cents. But wind and solar and nuclear energy don't go up -- because they don't cause asthma, and they don't emit carbon dioxide.

据那项最近发表的研究显示，将所有隐性成本计算入内后，不同能源的总成本看起来与之前的数据截然不同。如果是现有的燃煤电厂，每度电的成本将上涨六美分，使其真实成本变为九美分；如果是新建的燃煤电厂，每度电的成本将进一步上涨约四美分，至13.2美分。如果是新的天然气发电厂，成本将上涨1.3美分，使总成本增至7.5美分。但风能、太阳能和核能却不会上涨，因为它们不会导致哮喘，也不排放二氧化碳。

A few cautions when comparing the cost of different power sources. Gas plants are often used to meet peaking power demand, when they can fetch higher prices. Solar power also produces during hours of high demand, and its power is more valuable. But wind power produces more at night and less in the daytime, so its electricity is less valuable to the system.

在比较不同发电能源的成本时，有几点需要注意。燃气发电通常用来满足高峰时段的电力需求，这个时段它们可以售得更高的价格。太阳能发电也被用于需求量较高的时段，所以这些电也比较值钱。但风力发电多在夜晚进行，白天比较少，因此风能所发的电对整个电力体系来说没有那么重要。

Furthermore, different energy sources have additional costs that muddy direct comparisons. Nuclear plants have decommissioning costs, waste storage and liabilities that aren't always fully priced in. Variable sources such as wind and solar power need extra transmission lines and special efforts to integrate their power into the grid, which isn't included in the cost.

此外，不同能源都有额外成本，这也让成本变得难以直接对比。核电厂有核设施停运的成本，废料存储的花销以及应负的责任，这些未必总是全都计入价格之内。像风力发电和太阳能发电之类的可变电源需要有另外的传输线路，并且需要付出额外的努力将其并入输电网中，这也未算入成本内。

MYTH NO. 4: Variability Dooms Renewable Energy

谬误4 可再生能源的变化无常导致其注定会失败

The sun doesn't always shine, and the wind doesn't always blow, so wind farms and solar arrays generally punch below their weight. A 100-megawatt wind farm will generate on average the equivalent of 34 megawatts of power that's available full time.

太阳并不总是阳光闪耀，风也并非无时无刻吹个不停，因此风电场和太阳能电池阵的发电量通常低于预期。一个100兆瓦特的风电场平均可生产34兆瓦特可供全天24小时使用的电能。

Granted, there are forms of renewable energy that almost always generate power: geothermal plants and hydroelectric facilities, for example. But since the bulk of growth in renewables in the U.S. comes from wind and solar power, their variability is a flashpoint for critics and a technical challenge for grid operators. Variability costs money to deal with, requires some level of backup power to offset and can even lead to renewable-energy generation being wasted, note researchers at the Lawrence Berkeley National Laboratory. When power-grid operators either don't want or can't handle wind power, for instance, they just dump it -- a process called curtailment.

诚然，有些可再生能源几乎可以一直发电，如地热发电厂和水力发电厂。但由于美国可再生能源的大部分增长都来自风力发电和太阳能发电，它们的变化无常也就成了批评人士的焦点，同时也给电网运营商提出了技术上的挑战。劳伦斯伯克利国家实验室的研究人员指出，应对这种不稳定性需要资金，需要某种程度的备用电源对其进行补偿，这种不稳定性甚至还有可能导致可再生能源发的电被浪费。比如，当电网运营商不想要或无法处理风力所发的电时，他们就干脆丢弃它――这一过程被称作“弃风”。

Still, things are improving rapidly. Consider the situation with wind power. Curtailments have fallen steadily in recent years as system operators have gotten better at using forecasting and integrating wind power. Investment in new transmission lines has also picked up pace, enabling wind farms in isolated locations to offer power more readily to a wider area.

但是，事情发展依然迅速。想想风力发电的情况吧。随着电力系统运营商越来越擅于预测和整合风力发电，近年来弃风的比率已是稳步下降。对新输电线路的投资也跟上了步伐，这使得坐落在偏远地区的风电场向更广阔的地区供电变得更为容易。

That is the key to overcoming the natural variability of renewables such as wind and solar power. Individual wind farms may be very volatile. But scores of wind farms over thousands of square miles show less volatility -- the wind is always blowing somewhere. As grid operators have added more wind in more locations to their systems, as well as the lines to carry that wind, integrating wind power into the electricity system has become easier.

这也是克服风能和太阳能之类的可再生能源的天然多变性的关键所在。单独一个风电场有可能极为不稳定。但分布在数千平方英里上的大量的风电场，其不稳定性就小了很多――总有一个地方正在吹风。随着电网运营商将更多地方的风力发电纳入他们的系统，并且增加了输电线路，将风力发电并入电力系统变得越来越容易。

Take Texas. Four years ago, facing severe transmission constraints, the state was dumping 17% of all the wind power it produced. In 2012, after adding more wind farms and almost 2,600 miles of transmission lines, curtailments were below 4%, and wind power provided 10% of the electricity in the nation's biggest power market.

以得克萨斯州为例。四年前，由于面临着严峻的输电限制，该州放弃了17%的风力发电。2012年，在建设了更多的风电场和将近2,600英里的输电线路后，“弃风”下降至不到4%，风力发电为美国这个最大的电力市场提供了10%的电能。

MYTH NO. 5: Cheap Natural Gas Is the Enemy of Renewable Energy

谬误5 价格低廉的天然气是可再生能源的敌人

With the boom in U.S. natural-gas production, many concluded that renewable energies would be battered by a relatively clean, cheap fuel source. While natural gas has transformed the electricity sector, gas and renewables are actually complementary, not rivals.

随着美国天然气产量的增加，许多人认为，可再生能源有可能受到这种相对干 、便宜的燃料源的打击。天然气改变了电力行业，而天然气和可再生能源实际上是互为补充，而非对手。

A glance at national trends makes clear that the two energy sources can grow together. Natural-gas electricity generation rose 34% from 2009 to 2012. Wind generation rose 92% in the same period and solar generation almost fourfold, though the renewables grew from a much smaller base.

浏览一下全国趋势便能发现，两种能源可以共同增长。从2009年至2012年，天然气发电量上涨了34%，风力发电量上涨了92%，太阳能发电量增长了将近四倍。当然，可再生能源的增长基数要小得多。

Granted, cheap natural gas makes it difficult for wind power to compete without federal subsidies. But researchers are finding that gas and wind complement each other as part of a balanced electricity-generation portfolio.

的确，天然气很便宜，因此如果没有联邦财政补贴的话，风力发电要与之竞争非常困难。但研究者们发现，天然气和风能相互补充，成为了一个平衡的电力生产组合。

Look at it from a utility's perspective. Natural-gas plants have low upfront costs, don't rely on fickle federal subsidies, and their output can be dispatched to meet swings in power demand. Gas, therefore, gives reliable power now, with little worry in the short term about federal policies.

从公用事业的角度来看看这两者吧。天然气发电厂的预付成本很低，不依赖善变的联邦财政补贴，而且其产出可以用来应对电力需求摇摆不定的情况。因此，天然气目前是可靠的电力来源，短期内也不用太担心联邦政策。

But over the longer term, volatile gas prices could be deadly-as could environmental rules from Washington. That makes the wind farms and other renewable-energy projects an appealing way to hedge. Almost all of their costs are up front-there's no fuel to buy, so no worries about volatile prices. Because renewable energy doesn't produce any harmful emissions, it doesn't face the specter of future federal rules-and indeed could benefit from state rules mandating green power.

但从长期来看，不断变化的天然气价格以及美国政府的环境规定都有可能成为其致命之处。这使得风电场和其它可再生能源项目成为颇具吸引力的下注对象。这些项目几乎所有成本都是预付的，不用购买任何燃料，因此不用担心价格会变化无常。而且由于可再生能源并不产生任何有害排放物，因此也不用担心将来的联邦法规，甚至可以从强制发展绿色能源的州法规中获益。

MYTH NO. 6: Renewable Energy Means Millions of Green Jobs

谬误6 可再生能源意味着数百万个绿色岗位

During the 2008 campaign, Barack Obama touted the prospect that investing in clean energy could produce five million 'green jobs.' The idea of creating jobs helped underpin the $90 billion clean-energy stimulus in 2009 and later efforts, and remains a staple of administration rhetoric.

奥巴马在2008年大选中吹嘘称，投资清洁能源将创造500万个“绿色岗位”。创造工作岗位的理念在2009年帮助通过了900亿美元的清洁能源刺激法案以及后来的一系列行动，现在也依然是政府花言巧语的重要组成部分。

But renewable energy has not been the job creator that its boosters envisioned. While the amount of wind and solar power has more than doubled since President Obama took office, renewable-energy jobs have not.

但是可再生能源并没有成为其支持者所预想的工作创造者。自奥巴马总统就任以来，风力发电量和太阳能发电量已增长一倍有余，但可再生能源方面的工作岗位却没有增长。

The hardest part of sizing up green jobs is figuring out what a green job is. The Bureau of Labor Statistics came up with an expansive definition: goods or services that benefit the environment or make a company more environmentally friendly. According to the most recent data from the BLS, the U.S. had 3.4 million green jobs in 2011. But the categories are generous, to say the least. Private-sector green jobs included petroleum and coal-products manufacturing (3,244 jobs); school and employee bus drivers (166,916); logging (8,837); paper mills (18,167); and iron and steel mills (33,812). The numbers get so fuzzy as to become all but meaningless as an indicator of employment potential from clean energy.

估算绿色岗位最难之处在于弄清楚绿色岗位到底是什么。劳工统计局(Bureau of Labor Statistics)给出了一个非常宽泛的定义：对环境有利或者使一个公司变得更加环保的商品或服务。据劳工统计局最新的数据显示，美国2011年共有340万个绿色岗位。但至少可以说其涵盖的类别是非常宽泛的。包括石油和煤炭产品在内的私营部门的绿色岗位（3,244个）；学校和被雇佣的巴士司机（166,916个）；伐木业（8,837个）；造纸厂（18,167）；钢铁厂（33,812个）。这些数字如此模糊，作为衡量清洁能源就业潜力的指标毫无意义。

Direct-employment numbers from renewable energies are clearer. In 2012, the wind industry said it employed about 81,000, the solar industry employed about 119,000, and geothermal energy may have employed about 20,000. The Hydropower Association estimates the sector employs between 200,000 and 300,000 people today.

可再生能源行业的直接就业数据则比较清晰。2012年，风能行业称其雇佣了约81,000人，太阳能行业约为119,000人，地热能行业有可能雇佣了约20,000人。据水电协会(Hydropower Association)预测，该行业目前的就业人数大约在200,000至300,000之间。

Not only are those numbers quite modest, but in broad terms they haven't increased much since 2008, before the recent strong growth in renewables. In 2008, the wind industry said it employed about 85,000 people. So while installed wind capacity more than doubled, wind employment shrank. Solar employment stood at about 93,000 in 2010. Two years-and a ninefold increase in solar power-later, solar employment had increased just 28%.

这一数量不仅微不足道，而且从广义上来看，自2008年开始，直到最近可再生能源的强劲增长开始前，这些数字并没有增加多少。2008年，风能行业称，该行业雇佣了约85,000人。因此虽然风力发电装机容量翻了不止一番，该行业的就业人数却减少了。太阳能行业2010年大约雇佣了93,000人。随后两年内，太阳能发电量增长了九倍，就业人数却仅仅上涨了28%。

The contrast between the promise and the reality of green jobs becomes even clearer when compared with other energy sectors. Coal, for example, is shrinking as a share of the U.S. electricity mix. Nevertheless, total coal-sector employment of about 150,000 is the highest since the mid-1990s.

和其它能源行业相比，关于绿色岗位的承诺和现实之间的对比就更加清楚了。例如，煤炭在美国电力结构中的比例正在缩减。然而，整个煤炭行业雇佣了约150,000人，是自20世纪90年代中期来最高的。

And, by far, the biggest jobs story in the energy patch has come from the oil and gas boom. According to a fresh study by energy consultancy IHS Cera, unconventional oil and gas production-hydraulic fracturing, or fracking, for natural gas and tight oil-accounted for about 360,000 direct jobs.

而且，到目前为止，能源板块关于工作岗位的最大新闻来自石油和天然气的繁荣。能源咨询公司剑桥能源咨询公司(IHS Cera)一项新的研究发现，非传统的石油和天然气生产――用于获得天然气和致密油的水力压裂――直接创造了约360,000个工作岗位。