由于生产成本不断上升，用于替代石油的生物燃料及其他能源也面临着发展瓶颈，这一局面可能会挫伤人们未来几年通过发展替代能源来降低油价的努力。
几年前，很多能源经济学家就预言，油价高企将提升替代能源在经济性上的吸引力，从而推动生物柴油或风能等替代能源得到长足发展。
然而许多实际情况却与此预言相左。虽然原油价格已接近每桶100美元，但部分替代能源的吸引力甚至还不如以前。
原因之一在于，强劲的能源需求导致几乎每一种燃料的供应都面临不足，进而拉高了许多替代能源的原材料的价格。一些生物燃料的价格还要取决于农产品市场的行情，而这些作物的食用需求也在不断上升，使得价格进一步上涨。
虽然太阳能、核能和其他能源也一定程度的面临这个问题，但最突出的还属用农作物制造的替代能源，如乙醇和生物柴油。
业内分析师说，在原油价格只有每桶50美元的时候，用豆油和棕榈油等农作物生产生物柴油的经济效益与原油相比还有一定竞争力。
但原材料价格大幅上涨使得生物柴油行业的经济效益发生了急剧变化，比如棕榈油价格过去三年的涨幅就超过了90%。马来西亚棕榈油协会(Malaysian Palm Oil Association)前会长钱德兰(M.R. Chandran)表示，当前环境下，原油价格要上涨到每桶130美元，用棕榈油制造的生物柴油才能具备竞争力。
但其他石油替代品甚至是污染相对更严重的煤炭的价格都比以前高了。煤炭价格在过去四年上涨了一倍以上。与此同时，核电的关键原料铀的价格涨幅甚至超过了六倍。又例如硅，由于这种太阳能电池主要原料的供应出现短缺，过去几年太阳能电池的成本也在上涨。
ARC Financial Corp.首席能源经济学家彼得•特扎基安(Peter Tertzakian)称，成本标杆肯定已经变化了，在这种情况下，替代性能源要想吸引人们的兴趣就更困难了。这样一来，预计替代能源的普及速度将比人们预想的慢很多。ARC Financial是加拿大阿尔伯特省卡尔加里的一家私人股权投资公司。
当然，许多替代能源在过去三年还是取得了长足的发展，而且，若不是有这些替代能源，那原油价格几乎可以肯定会比现在更高。亚洲和其他国家及地区过去几年已在建设新核电站和液化天然气相关设施方面投入了数十亿美元，在太阳能和风能方面的投入也大幅增加。
去年全球乙醇产量达到135亿加仑，较2004年增长25%。与此同时，生物柴油产能也增加一倍以上，达到610万吨。然而，两种燃料在全球运输工具燃料供应中所占比例仍只有1%左右。据国际能源署(International Energy Agency)称，生物燃料及前苏联国家和巴西等国出产的石油明年将在非石油输出国组织(OPEC)新增能源供应中占据相当大的比重。
或许更重要的是，自2004年以来有大量的风险资本涌入替代能源行业，由此，未来几年靠先进技术降低成本的希望大大增加。
穆迪(Moody's)旗下财经网站Economy.com首席经济学家马克•赞迪(Mark Zandi)称，替代能源的发展尚处于早期阶段，油价是从四年前才开始上涨，我认为大家都太没有耐心了。
然而，替代能源成本近期的飙升以及对环境问题的担忧日益加剧促使各国政府纷纷对在替代能源上所作的投入作出反思。一些国家对此类能源今后能否像人们最初预想的那样发挥巨大作用提出了疑问。
作为全球重要的棕榈油生产中心，马来西亚已暂停实施要求加油站在汽油中混合生物柴油的规定，因为他们担心此规定或许会进一步推升棕榈油价格，从而损害该国新生的生物柴油行业。
马来西亚过去三年共发放了90张生物柴油生产牌照，但至今只有大概五家还在经营。其他拥有牌照的厂商似乎在棕榈价格回落之前还将继续观望。
欧洲国家仍在为实现到2020年将生物燃料油在交通燃油中所占比例提高至10%这一计划而努力。不过，德国已减少了对生物燃料的部分税收优惠，一些欧盟官员也对将来向种植生物燃料作物提供补贴的必要性提出质疑。西班牙能源公司Abengoa SA旗下一家生物燃料生产厂最近已因粮食价格过高而停产。包括匈牙利在内其他国家的同类项目也已被叫停。
美国的替代燃料行业也面临着困境。乙醇主要原料玉米的价格在节节攀升，而乙醇价格却因供应过剩而下跌。其结果是乙醇厂商的利润受压，新进入的厂家被迫取消或推迟建设新生产设施。
有一些经济学家担心，只要油价居高不下，现在的这些问题就会继续存在，并且短期内难以得到解决。他们指出，一些非石油燃料与原油一样面临着供应方面的限制。受土地和水资源限制，我们可能无法生产出足够多的能将生物燃料价格维持在低水平所需的作物。虽然煤炭储量依然丰富，但也面临着品位下降和老煤矿开采成本增加等问题。铀的供应则受到铀矿开发周期长和其他因素的制约。
另外还有人担心，随着越来越多的非石油商品与石油替代品扯上关系，这些商品在定价时也会逐渐考虑到与原油定价相同的因素，进而导致它们的成本走势与国际油价保持一致。
比如，在本轮能源市场大涨之前，棕榈油主要是作为食用油，其价格起伏并不受原油价格影响。而如今棕榈油作为能源来源的色彩越来越浓，结果是过去三年来棕榈油价格的涨幅与原油基本一致。
不过也有迹象显示，上述这些疑虑有些可能是被夸大了。例如，作为乙醇主要生产原料之一的糖，其价格自2006年初以来下跌了四成以上，原因是印度等国的供应量显著增加。
Patrick Barta
Rising costs of biofuels and other alternative energies are making them less viable as substitutes for crude oil, a development that could frustrate efforts to bring oil prices down in the years ahead.
A few years ago, many energy economists predicted that higher oil prices would ensure the success of alternative energies such as biodiesel or wind power by making them more financially attractive. In many cases, though, the opposite has occurred: Even as crude-oil prices approach $100 a barrel, some alternatives look less attractive than in the past.
One reason: Energy demand is now so intense that supplies of just about every kind of fuel are in short supply, driving up prices of the raw materials involved in making many alternative energies. Some biofuels also rely on agricultural commodities that already are facing higher demand as foodstuffs, a situation which drives up prices further.
The problem is most acute for crop-based alternative fuels, like ethanol and biodiesel, though it has also proved true to some degree for solar power, nuclear power and other competing energy sources.
Biodiesel, a fuel made from farm crops like soybean oil and palm oil, was in some cases supposed to be economically competitive with crude-oil prices as low as $50 a barrel, according to analysts who studied the industry.
But a sharp rise in the price of biodiesel raw materials -- including a more than 90% jump in palm-oil prices over the past three years -- has dramatically altered the economics of the industry. M.R. Chandran, former head of the Malaysian Palm Oil Association, says crude oil would now have to be as much as $130 a barrel before palm-oil-based biodiesel is competitive.
Other alternatives to oil, including relatively dirty ones such as coal, have also become more expensive. Coal prices have more than doubled over the past four years, and prices for uranium, a crucial ingredient in nuclear power, have increased more than sevenfold in that time frame. The cost of solar-power cells has been pushed up in the past few years by a tight supply of silicon, the main raw material in such cells.
'The cost goal posts have certainly shifted,' and that is making it harder for alternatives to oil to gain traction, says Peter Tertzakian, chief energy economist with ARC Financial Corp., a Calgary, Alberta, private-equity investor. As a result, 'the rate of adoption that people expected is going to be a lot slower than people think.'
Of course, many types of alternative energy have made considerable progress over the past three years, and crude-oil prices would almost certainly be higher now if such fuels weren't in the mix. Asia and other parts of the world have rolled out billions of dollars for new nuclear-power plants and liquefied-natural-gas facilities over the past several years, and spending on solar and wind power also has soared.
Global ethanol production rose 25% from 2004 to 13.5 billion gallons last year, and biodiesel capacity more than doubled to 6.1 million metric tons in that period, though the two combined still only make up about 1% of the world's transportation-fuel supply. Biofuels -- along with oil from the former Soviet Union and Brazil -- are expected to account for much of the new energy supply developed outside the Organization of Petroleum Exporting Countries next year, the International Energy Agency says.
Perhaps most important, huge sums of venture-capital cash have flooded into the alternative-energy sector since 2004, raising the odds that technological advances will bring down costs in the years ahead.
'It's early in the game; it's only been four years since energy prices have risen, and I think we're all just too impatient,' says Mark Zandi, the chief economist of Moody's Economy.com, a West Chester, Pa., research firm.
Still, the latest surge in alternative-energy costs -- along with growing concerns about their environmental sustainability -- are forcing governments to rethink their commitment to such fuels. Some have begun to question whether they will play as big a role in the future as first hoped.
In Malaysia, an important center for palm-oil biodiesel production, the government has held back on plans to require biodiesel blends at petrol stations because of a fear it could drive palm-oil prices too high, imperiling the country's nascent biodiesel industry.
Malaysia issued roughly 90 permits for biodiesel refineries in the past three years, but only about five are in operation. It appears that most of the others will remain on hold until palm-oil prices come back down.
In Europe, officials are still committed to a plan to meet 10% of the region's transportation needs with biofuels by 2020. But Germany has cut back on some tax incentives for biofuels, and some EU officials have questioned whether subsidies for biofuel crops are necessary in the future. Spanish energy company Abengoa SA recently suspended production at one of its biofuel facilities in Spain because of high grain prices. Similar projects have stalled elsewhere, including Hungary.
The U.S. has its own alternative-fuel woes. The price of corn, a key raw ingredient, has increased even as the market price for ethanol has been held down by oversupply. That has squeezed the profitability of ethanol producers and forced new players to cancel or delay construction of more facilities.
Some economists now fear that the current problems may remain as long as oil stays expensive and won't be easily fixed in the short term. They note that some nonoil fuels face the same supply constraints as crude oil. There may not be enough land or water to produce all the crops needed to keep biofuel prices low. Coal, while still plentiful, faces deteriorating grades and rising costs in older mines. Uranium supply is limited by the long lead times required in developing new mines, among other factors.
Another concern is that as more nonoil commodities evolve into oil alternatives, they will start to be priced the same way as crude, keeping their costs in line with international oil prices.
Before the latest energy boom, for instance, palm oil was viewed primarily as a source of cooking oil, and its value didn't rise and fall with crude oil. Now, it is increasingly seen as an energy source. Over the past three years, palm oil's price has risen by roughly the same amount as crude oil.
But there are signs some of these fears may be overblown. The price of sugar, a key element of ethanol, has dropped more than 40% since early 2006 as supply expands in places such as India.
Patrick Barta