这个答案相当复杂，牵涉到许多很重要因素，比如我们既不知道圣诞老人的飞行路线，也不知道雪橇的形状和飞行速度，更不清楚所有礼物的重量，不过，我们可以来凭经验大胆地推测一下。最终答案：圣诞老人飞一晚上的燃油成本将近5400万美元。

　　每逢年末，全球成千上万的孩子们都急切地等待着圣诞老人能送来礼物和美好的祝福。但如果圣诞老人来不了怎么办?要是今年负责拉雪橇的驯鹿集体感染了类似疯牛病的“疯鹿病”，圣诞老人被迫取消节日怎么办?其结果会是一场大灾难。

　　不过，要是读者中有小朋友的话，告诉你们一个好消息：北极官方表态称，今年圣诞老人的雪橇做了一些升级处理，万一驯鹿病倒，还可以利用飞机燃油运行。而且由于全球石油市场供过于求，即使驯鹿想照常执行任务，圣诞老人也有可能给它们放一晚上假，选择烧油出行。

　　那么，圣诞老人在24日晚上飞遍各地究竟需要花多少油?

　　这个答案相当复杂，牵涉到许多很重要因素，比如我们既不知道圣诞老人的飞行路线，也不知道雪橇的形状和飞行速度，更不清楚所有礼物的重量，不过，我们可以来凭经验大胆地推测一下。

　　一桶原油的标准容量是42加仑(约合159升)，通常可制成多种产品。平均每桶油有51%会炼成汽油，另有12%最终可用作航空燃油。假设圣诞老人将使用的是标准航空燃油，按比例来算，每提炼一加仑这类燃油需要消耗约8加仑原油

　　接下来，我们需要大致了解圣诞老人的油耗水平。一加仑燃油能飞多少英里?现在还不知道雪橇的具体重量和形状，但我们或许可以把它想象成一辆外观看上去像雪佛兰SUV、但能像C-5 “银河”军用运输机一样装货，速度又能达到F-22“猛禽”战斗机水平的混合体。按战斗机和C-5运输机的标准来看，每一加仑燃油可供其飞行0.1-0.5英里(0.16-0.8公里)。而波音747这样的大型宽体客机每飞行一英里需消耗约5加仑燃油。

　　当然，那些飞机都比圣诞老人的雪橇大得多(想象一下可怜的红鼻子驯鹿鲁道夫拉着一架波音787飞机是什么场景)。而一架小型商务喷气机Learjet每消耗约一加仑燃油可以飞行2.75英里。一架Piper Cub轻型飞机每耗约一加仑燃油飞行15英里。如果提高飞行速度，圣诞老人的燃油利用率就会下降。要在一夜之间拜访全世界的孩子们，他需要的速度应该比Piper Cub的每小时65节快得多。单说起飞，他的速度就要达到每小时约180英里。考虑到雪橇的设计者可能不大了解有关飞机怎样产生升力的伯努利原理，起飞速度恐怕要更高。因此Suburban车的大小可能最适合圣诞老人的雪橇，至于油耗，估计每加仑燃油(约8加仑原油)能飞行约5英里吧。

　　正好眼下能源市场动荡，睿智的投资者迎来了千载难逢的良机。

　　虽然主流媒体还在说油价已经跌得不知道底在哪里，但高明的石油投资者已经开始为下一轮出手做好充足准备。现在来算算圣诞老人到底需要飞多远?全球约有73亿人，根据每家五口人计算，老人需要走访全球15亿个家庭。当然了，并非所有人都过圣诞节，可无论是否基督徒，很多人都重视这个节日。一些估算数据显示，全球约45%的人口庆祝圣诞，意味着圣诞老人要拜访约6.75亿个家庭。按每平方英里约有7户人家，并且这些过节的家庭居住比较集中(可以合理地推测，同一宗教信仰的人一般聚居在一起)推算，圣诞老人得走遍地球9400万平方英里的范围。

　　对圣诞老人而言，如何以最高效率走访6亿多家庭是一个非常复杂的数学问题。假设他希望每平方英里都以对角线轨迹飞过(根据勾股定理需要飞行1.41英里)，而这些家庭又按比例平均分布在以一英里见方的土地上，圣诞老人要尽量高效地探访每一平方英里的人家就必须飞过2.41英里以上距离。(可以用多种数学程式建模，根据人口分布计算哪条飞行路线的效率最高，这只是基于上述假定前提做出的合理估算。)

　　因此，若要将礼物成功派送给世界各地的孩子，圣诞老人就得飞越大概2.26亿英里。前提还是尽量缩短在每家的逗留时间(一到地方就必须迅速放下礼物)，而且每次起飞都不要加油。

　　根据我们上面计算出的5英里/加仑的油耗，圣诞老人一年一度的圣诞任务需要耗费约4500万加仑燃油。当前现货市场的燃油价格正处于历史低位，约为1.20美元/加仑，算下来圣诞老人飞行一晚上的燃油成本将近5400万美元。我们再仔细想想，也许该让那八只驯鹿停止吃草准备开工了。

　　Every year around the world, hundreds of millions of children wait anxiously for Santa Claus to arrive and bring presents and good cheer. But what if Santa never came? What if this year the reindeer all fall ill, perhaps due to Crazy Reindeer disease (the analog to Mad Cow) and Santa is forced to cancel Christmas? The result would be devastating.

　　Fortunately, for any children reading, official word from the North Pole is that Santa’s sleigh has some new upgrades this year that allow it to run on good old fashioned jet fuel if the reindeer fail. And with the current glut of oil around the world, fuel prices are so affordable that even if the reindeer are feeling up to their usual task, Old Saint Nick might just give them the night off and choose to fly with fuel nonetheless.

　　So how much oil does Santa need for his rounds on the night of the 24th?

　　Well the answer is complicated by a number of factors most importantly, we just don’t know a lot of about Santa’s rounds, the shape of the sleigh, the air speed of the craft, or the weight of all those presents. But, we can take some educated guesses.

　　One 42 gallon barrel of oil is typically used to make a variety of different products. About 51 percent of the average barrel ends up being used for gasoline, while 12 percent ends up being used for jet fuel. Let’s assume then that Santa’s going to use standard jet fuel, and that 12 percent ratio holds – so for each gallon of jet fuel, we need around 8 gallons of oil. Recognizing that the byproducts of a processed barrel of oil are greater than the original 42 gallons, this 2:1 ratio is still a good place to start as a rough rule of thumb.

　　Next we need to get a rough idea of Santa’s fuel economy. How many miles does he go on a gallon of jet fuel? It’s not clear how much Santa’s sleigh weighs, or what it is shaped like, but we can probably envision it as something like a cross between a Suburban, a C-5 Galaxy fright aircraft, and an F-22 Raptor fighter jet. The sleigh looks blocky like a Suburban, carries about the same level of cargo as much as C-5 might, yet has the speed of a fighter jet. The fighter jet and c-5 achieve a fuel economy around the range of 0.1 miles per gallon to 0.5 miles per gallon. A 747 for instance burnsaround 5 gallons of fuel per mile.

　　But of course, those aircraft are all much larger than Santa’s sleigh. (Imagine poor Rudolph trying to pull a Dreamliner!) A Lear Jet uses around 1 gallon of fuel per 2.75 miles (based on a speed of 465 knots or 535 miles per hour). A Piper Cub uses about 1 gallon per 15 miles. Santa’s fuel economy is going to fall offthe faster he goes, and to get to all the children of the world in one night, he is going to need to go a lot more than the Piper cub’s 65 knots per hour. Just to take off, Santa is going to need to hit about 180 miles an hour, and probably more than that given the sleigh designer’s seem to have a weak grasp onBernoulli’s principle. Thus the Suburban is probably a good size comparison for Santa’s sleigh, and one might estimate the sleigh gets about 5 miles to 1 gallon of jet fuel (8 gallons of oil).

　　The current market turmoil has created a once in a generation opportunity for savvy energy investors.

　　Whilst the mainstream media prints scare stories of oil prices falling through the floor smart investors are setting up their next winning oil plays.Now how far does Santa need to go? There are around 7.3 billion people in the world, which works out to around 1.5 billion households around the planet based on around 5 people per household. Now not everyone celebrates Christmas of course, but many Christians and non-Christians alike do. By some estimates, perhaps 45% of the world’s population celebrates Christmas. That means that Santa needs to visit about 675 million households. With about 7households per square mile, and assuming that households celebrating Christmas are clustered (which seems logical given religious clustering), that means that Santa has to cover around 94 million square miles of households.

　　The most efficient mechanism for Santa to cover these households is a very complexmathematical problem. But assuming Santa wants to fly diagonally over each square mile (for a distance of 1.41 miles based on the Pythagorean Theorem), and households are on average distributed proportionally across this each 1 mile block, then Santa will have to fly over 2.41 miles of ground to cover each square mile as efficiently as possible. (You can use a variety of mathematical algorithms to model the most efficient flight path depending on population dispersion – this is just a reasonable approximation based on the assumptions outlined above).

　　As a result, Santa needs to travel around 226 million miles to deliver all of the presents to the world’s children. This assumes minimal idle time on each rooftop (he’s got to scarf down those cookies quickly), and abstracts away from the extra fuel needed for each takeoff.

　　Given our 5 miles per gallon of jet fuel efficiency calculated above, that means Santa needs around 45 million gallons of jet fuel for his annual voyage. With jet fuel going for around $1.20 a gallon right now on the spot market, and prices lookinghistorically low, this puts the total fuel cost of Santa’s journey at a bit less than $54 million for one night. On second thought, maybe it’s time to break out the hay for those 8 reindeer.

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（编辑：何莹莹）