AAAS Diary: Number Crunching

Reporter Graeme Stemp-Morlock blogs from the annual meeting of the American Association for the Advancement of Science (AAAS) in San Francisco.

Steven Chu loves sustainable numbers.  And, the Director of the Lawrence Berkely National Laboratory and Nobel Laureate had a wealth of interesting ones relating to his AAAAS keynote address “The Energy Problem and What We Can Do To Solve It”.

For instance, Chu began his talk with the astounding figure that the USA spent $250 billion in 2005 to import fossil fuels.  Even worse though is the $750 billion energy trade deficit in 2005.  “So, it is in our best interest to get off oil,” said Chu matter-of-factly.

Solar power is the way to get off oil Chu believes and he is backing that position up with numbers too.

First, Americans use 350 billion joules of energy per person per year, which means absolutely nothing to any normal person.  But, if you pretend that you are a rich prince with servants waiting on you hand and food, and your servants need 3000 kilocalories to fill your bubble bath that means you would have about 1000 servants.  (Europeans only have 300-400 servants by the way….they fill their own bubble paths)

To have the entire world attain the 300 odd servants that the average European has would require that we harness only 0.04% of the solar power that hits the Earth.

Now, you might think that it would require a huge land area to collect all that sunlight, and you would be both right and wrong.  Right, because it is a large area of land; wrong because to power the entire USA at 300 servants a piece with photovoltaics that are only 15% efficient would require about 0.2-0.3% of the non-arable land (an area that fits nicely into the soon-to-be desert regions of the Midwest).

But photovoltaics are only part of the plan to capture the sun’s power.  The other part involves growing weeds for fuel.  By using a weed high in cellulose, Chu claims to get 26 dry tones per acre and by planting this goliath weed on waste farmland you could meet a third of the US fuel demand.

Oh, and the other numbers Chu like are just as impressive.  Chu’s Helios Project (a lab that will be part of Lawrence Berkeley and will have interdisciplinary studies on how to harness the sun’s power) has received donations of $500 million from BP, $70 million from Governor Schwarzenegger, and $250 from the Department of Energy.  I think even the most math phobic person could deal with those numbers.