Thursday, September 13, 2007

Can whales solve the oil crisis?

With oil prices flirting with new all-time highs, there has been a lot of talk about the global oil crisis recently. A combination of the price, the peak oil hypothesis, global security issues, and global warming means that the industrialized world’s reliance on petroleum is increasingly being questioned.

One increasingly popular alternative to petroleum is some sort of biofuel; that is oil derived from organisms that have been killed recently, instead of having died millions of years ago. There is a historical precedent for biological oil production; during the first 70 or so years of the industrial revolution, prior to the discovery of petroleum, oil was mainly produced by the whaling industry.

Needless to say, the global thirst for oil has increased since the days of Moby Dick and the old Nantucket sailing ships. But it is still a useful exercise to determine just how many whales would have to be harvested to supply the modern world with oil. In deference to the cultural and literary value of the sperm whale, we will use it as our cetacean of choice for the following calculations.

The current annual production of petroleum is just a shade under 30 billion barrels. Simply dividing this number by the oil that can be produced from each whale should tell us how many whales we will need.

According to industry website SaveTheWhales.org, a sperm whale could produce 2000 gallons, or 47.6 barrels, of oil. Thus a touch of long division tells us that we will need to slaughter approximately 630 million sperm whales each year in order to completely replace our petroleum production. Since there are only an estimated one million sperm whales currently living on Earth, wiping out the entire species would power the global economy for about half a day.

Clearly, a whale breeding program is needed to make such a scheme feasible.

Trouble is, whales are not rabbits. With a slow breeding species like sperm whales, we can only afford to harvest a small percentage- say, 10%, of the total stock each year if we are to use their oil in a sustainable fashion. So in order to have an annual 630 million whale kill, we will actually need a total population of about 6.3 billion animals. That’s about two whales for each person on earth.

And those 6.3 billion whales will get very hungry. Sperm whales have an unusual diet, which consists almost entirely of giant squid. And although the exact rates of consumption are not known, a good ecological rule of thumb for carrying capacities is that predators need a prey population with a body mass that is 10-1000 times larger than that of the predators.

Using a geometric average of 100 times per food chain step, and an average whale mass of 40 metric tones, we will need about 2.5x1016 kilograms of squid to feed our whales. That’s either 840 million billion calamari rings, or a single mollusk that is twice the mass of the Martian moon Phobos. Such a squid is illustrated below.

And because squid are not autotrophic, they too will need something to eat. 2.5x1016 kg of squid will need to eat 2.5x1018 kg of fish, which will need 2.5x1020 kg of zooplankton, which in turn will require 2.5x1022 kg of phytoplankton. This is either an absurd number of microbes, or a giant foram that is one third the size of our moon. And this is where things get tricky.

The Earth’s hydrosphere contains a mere 1.4x1021 kg of water, meaning that it is insufficient to host the phytoplanktonic base of our food chain. Thus we will need to move our whale breeding program to another celestial object, where more water is available. Fortunately, several such objects are available in our solar system.

Ganymede, the mercury-sized moon of Jupiter, has a mass of 1.5x1023 kg, more than half of which is water. Assuming that algal blooms can happily grow at concentrations of 30% of the water mass, this Galilean satellite would be a perfect place to host our whale breeding stock, provided that we can thaw it out. And this should not be too hard to do.

Ganymede, which is gravitationally bound to the giant planet Jupiter, orbits more than 500 million kilometers from the nearest swing electorate. There are relatively few special interest groups or corrupt corporations with a vital interest in the icy satellites of Jupiter, so the only barriers to harnessing this planetoid to fight global warming are physical, not political. Therefore, transporting this enormous iceball to Earth orbit and turning it into a cetacean breeding pool should be substantially easier than producing electric cars, or putting up windmills in Senator Kennedy’s backyard.

I suggest that we simply pop Ganymede into a 1:2 orbital resonance with our current moon. This would give Ganymede an orbital period of two weeks- a useful time frame for the commodities futures market. It would also give us great solar eclipses, and wicked tidal currents. As the whales are needed, they can simply be catapulted into a collision course with Earth, using a trajectory that minimizes the burnup of blubber during re-entry.

While this scheme may seem hare-brained and overly ambitious to some, it is far more practical than taking the bus to work, or driving a Prius.

6 comments:

ScienceWoman said...

This is great. But I shudder to think how long you spent doing the math and finding the images. Where do you get these ideas!??!

Dr. Lemming said...

The hardest part was actually finding a number for oil yield per sperm whale. The rest was trivial- wrote it up in camp by head-torch after lights-out.

I figured since I can only post every few weeks, I might as well put some effort in.

Mark said...

The underlying fallacy here is that you forgot about abiotic processes - such as those allowed by anti peak oilers for the endless supply of the black stuff. Presumably this works too for sperm whales, so that you have severely underestimated the number of sperm whales that are actually available for harvesting. We just need to increase exploration for more sperm whales. Silly you.

CelineSSauve said...

30 million barrels/year
47.6 barrels/whale

30,000,000/47.6
=630,253 (rounded up to be safe) whales/year

Where did you get 630,000,000 (630 million)?

I also feel pressed to point out that those who, for whatever reason, don't want the oil from the corn which is presently produced would probably mention that there are other species of whale in our seas.

Mike said...

A typo in the original post: 30 BILLION barrels per year.

The other figures are correct(ish)

Dr. Lemming said...

Thanks! Fixed the typo. Also, there is a followup post:
Cetacean Liposuction