Fossil fuels have had an aeon’s head start
可再生能源真能竞争过化石能源吗？
广州化石翻译公司：哈福德：化石能源不可能在短期内用光，可再生能源也难以变得比化石能源更有竞争力，但我们必须完成能源转变。
Will we ever stop using fossil fuels? The question matters because fossil fuels are the largest contributor to climate change. Although finding better ways to produce cement, combat deforestation or even reduce the flatulence of cows and sheep would all be welcome, our only hope of dramatically cutting greenhouse gas emissions is to find cleaner methods of generating power.
我们是否会停止使用化石能源呢？这个问题很重要，因为化石能源是气候变化的最大致成因素。尽管找到更好的办法来生产水泥、防止森林砍伐、甚至减少牛羊肠胃胀气都不错，但我们大幅削减温室气体排放的唯一希望是找到更清洁的发电方法。广州化石翻译公司。
This won’t be easy. Coal, gas and oil are wonderfully concentrated sources of energy, neatly synthesising aeons of solar radiation. The late Professor David MacKay, author of the remarkable Sustainable Energy — Without the Hot Air (2008), underlined that truth with the book’s pointed dedication “to those who will not have the benefit of two billion years’ accumulated energy reserves”. The concentrated nature of fossil fuels means that alternative energy sources are competing against a formidable head start; the head start is lengthened by the fact that our entire existing energy system revolves around fossil fuel.
这并不容易。煤炭、天然气和石油是极为浓缩的能源，蕴含了亿万年的太阳辐射能。已故的戴维•麦凯(David MacKay)教授在其非凡之作《可再生能源——拒绝空话》(Sustainable Energy — Without the Hot Air, 2008)中强调了这个事实，并着意将这本书献给“那些以后无法享受20亿年积累的能源储备的人”。化石能源的浓缩性意味着替代能源要和这种巨大的起步优势竞争；这种优势还因为我们现有的整个能源体系都围绕着化石能源建立而得到了延长。
Despite all this, there are two obvious scenarios in which we might replace fossil fuels with alternative energy sources for purely commercial reasons. The first is grim: we begin to run out of fossil fuels and they become too expensive to use as a source of bulk energy. The second, more benign possibility, is that alternative energy sources become so cheap as to outcompete coal, gas and oil at almost any price; as the former Saudi oil minister Sheikh Yamani once commented, the Stone Age did not end because we ran out of stones.
尽管如此，在两种显而易见的情况下，我们可能会因为纯粹的商业原因用替代能源代替化石能源。第一种情况较为严峻：我们的化石能源渐渐用光，它们变得过于昂贵，无法用作主要能源。第二种更加良性的可能性是替代能源变得非常便宜，以至于在几乎任何价格上都比煤炭、天然气和石油更有竞争力；就如沙特前石油部长谢赫•亚马尼(Sheikh Yamani)曾经评论的，石器时代并不是因为我们用光了石头才结束的。广州化石翻译公司。
The grim scenario is unlikely, because we are unlikely to run out of fossil fuels any time soon. According to the BP Statistical Review of World Energy, we have used up all the proven oil reserves that existed in 1980, yet have more than we started with. Gas reserves aren’t falling either. (Coal reserves are, but from immense levels.) This shouldn’t be too surprising: “proven reserves” are resources that have been identified, measured and look profitable. As old reserves are exhausted, new reserves are sought to replace them and, so far, we have had little trouble in finding more fossil fuels whenever we wish to.
第一种情况不太可能发生，因为我们不太可能在近期内用光化石能源。根据《英国石油公司世界能源统计年鉴》(BP Statistical Review of World Energy)，我们已经用完了1980年已探明的石油储量，然而现在探明的石油储量比那时多。天然气储备也并未下降。（煤炭储量的确在下降，但基数非常巨大。）这不应该太让人惊讶：“已探明储量”是已经确定、测量并且看起来可以盈利的资源。在旧的储量耗尽时，人们会寻求用新的储量来替代它们。到目前为止，只要我们想，我们不难找到更多的化石能源。
Another way to observe this is to look at economic behaviour. If the supply of oil was limited and known, owning an oilfield would be like owning any other investment. Producers would have to decide when exactly to sell their finite barrels of oil, and the only logical path for the oil price would be a gentle upward trend, matching the rate of return on other assets such as shares or bonds. (Any other price-path would be self-defeating: a lower price tomorrow would provoke a rush to sell immediately; a sharply higher price tomorrow would mean no oil was sold today.) This well-known theory, demonstrated by the economist Harold Hotelling in 1931, is, of course, in contradiction to the actual behaviour of oil and gas prices: fossil-fuel producers are clearly not treating oil and gas as though they were non-renewable resources.
对这个问题进行观察的另一种方法是看一看经济行为。如果石油的供给是有限且已知的，那么拥有一个油田就像拥有任何其他的投资一样。生产商必须决定具体在什么时候卖出他们有限的石油，石油唯一合理的价格路径就是趋于平缓向上，与股票、债券等其他资产的回报率类似。（其他任何价格路径都将是自相矛盾的：如果明天价格较低，今天人们就会竞相抛售；如果明天价格要高得多，那就意味着今天没人会卖出石油。）经济学家哈罗德•霍特林(Harold Hotelling)在1931年阐述了这个著名的理论。当然，这个理论并不符合石油和天然气价格的实际变动情况：化石燃料生产商显然并没有把石油和天然气当作不可再生的能源。广州化石翻译公司。
But the cheerier scenario, in which low-carbon energy sources become very cheap, may be unlikely too. At first glance the signs seem promising — Denmark, Germany and Portugal have all reported occasions this year when their entire electricity grid was fuelled from renewable energy sources. And photovoltaic solar power, in particular, has become dramatically cheaper, largely for the simple reason that China has over-subsidised production of the panels, which now come in easy-to-install kits.
但更令人鼓舞的情景，也就是低碳能源变得非常便宜的情况，或许也不太可能发生。乍看之下，现在的迹象似乎很有希望——丹麦、德国和葡萄牙今年都曾宣布在某个时点实现了全电网由可再生能源供电。尤其是，太阳能光伏发电已经变得便宜得多，这主要是由于中国对太阳能电池板生产的过度补贴，现在电池板已经是容易安装的组件。
But it is too soon to declare victory. On a commercial basis, renewable energy sources must do more than outcompete fossil fuels on price. Solar and wind deliver power when the sun shines or the wind blows. Fossil fuels deliver power when people need it. That is a big advantage.
但要宣告胜利还为时尚早。在商业化方面，可再生能源必须不仅仅在价格竞争力上超过化石燃料。太阳能和风能分别能在阳光照耀和刮风的时候为人们提供电力。化石燃料却能在人们需要的任何时候提供电力。这就是一个巨大的优势。
And because fossil fuels pack a lot of energy into a small space, they’re ideally suited for transport. Electric cars are not competitive. A recent survey in the Journal of Economic Perspectives by the economists Thomas Covert, Michael Greenstone and Christopher Knittel estimates that current fuel cells would only be cheaper than gasoline at an oil price of $425 a barrel, eight times current levels. Fuel cells will fall in price, of course, but that figure gives a sense of the scale of the challenge.
而且，因为化石燃料在极小的空间中浓缩了大量能源，它们非常适合运输。电动汽车不具备竞争力。《经济展望期刊》(Journal of Economic Perspectives)刊载的一项近期的调查中，经济学家托马斯•科弗特(Thomas Covert)、迈克尔•格林斯通(Michael Greenstone)和克里斯托弗•尼特尔(Christopher Knittel)估测，只有当原油价格达到每桶425美元，也就是8倍于当前价格水平的时候，现在的燃料电池才会比汽油便宜。当然，燃料电池的价格会下降，但这个数字体现出挑战的艰巨性。广州化石翻译公司。
And nuclear energy? Economist Lucas W Davis, again in the Journal of Economic Perspectives, concludes that there is little prospect of a nuclear renaissance because nuclear power stations simply cost too much to build. It would require a large upward shift in the price of fossil fuels, not to mention a change in the political winds, to see the technology return at scale.
核能呢？同样是在《经济展望期刊》上，经济学家卢卡斯•W•戴维斯(Lucas W Davis)得出结论，核能的复兴不太有希望，因为核电站的建设成本实在太高。核能技术要想大规模回归，就需要化石燃料的价格出现大幅上升，更不必说还需要政治风向的改变。
Overall, there is little prospect of running out of fossil fuels, and it seems unlikely that alternative energy sources will outcompete them. And yet we must make the shift, or risk catastrophic climate change. Our reserves of fossil fuels may be no constraint but the atmosphere’s capacity to safely absorb carbon dioxide is.
整体上，用光化石燃料的可能性不大，替代能源的竞争力超过化石能源似乎也不太可能。然而我们必须完成能源的转变，否则就可能遭遇灾难性的气候变化。我们的化石燃料储量可能是无限的，但大气层安全地吸收二氧化碳的能力是有限的。
There is some space for optimism. Renewable energy sources are no longer impossibly costly. Nor is nuclear power, even though the costs have moved in the wrong direction. We cannot wait for the market to make the switch unaided — but the gap is no longer so wide that sensible policy cannot bridge it. The centrepiece of such a policy would be to raise the price of carbon dioxide emissions, using internationally coordinated taxes or their equivalent. Such a tax would make renewable energy sources more attractive — as well as encouraging energy-efficient technologies and behaviour. Market forces can do the rest. Low-carbon energy is not free — but it is worth paying for.
有一些保持乐观的空间。可再生能源不再昂贵得不可企及。核能也是如此，尽管其成本已经走上了错误的方向。我们不能等待市场独力完成这一转变——但其中的差距已经不再难以逾越，合理的政策能够在其间架起桥梁。这种政策的核心应该是利用国际协调税收或者类似机制提高二氧化碳的排放成本。这会让可再生能源更具吸引力，同时也会鼓励节能技术和行为。市场力量可以完成剩下的事情。低碳能源不是免费的——但为其花钱是值得的。
Tim Harford is the author of ‘The Undercover Economist Strikes Back’.
本文作者著有《卧底经济学家反击战》(The Undercover Economist Strikes Back)
