Fossil fuel will eventually runs out, one of the solutions to the environment problem is switch to biofuel.  Biofuel is produced by convernting plants into ethonal.  Plants is 100% renewable energy.  As long as there is land, water and sunlight, plants will grow every year.  Although biofuel is a clean energy, there are controversials about biofuel will disrupt food production.  I believed in this myth in the past and have doubt about the use of biofuel.  It turns out that is only true for 1st generation biofuel made from grains or corns.  The 2nd generation biofuel made from cellulor plants like grass or algae will have a 100 fold increase in efficiency.  We can produce enough biofuel to fill up all our gas tanks without affecting food production.  According to a news report, the effect of biofuel on food production is less than 1%.  Developed countries already waste more than 1% of food, so making biofuel should have virtually no impact on the food price.

I quoted the news in an online discussion about renewal energy and environmental problem. My view point is the Earth have more than enough energy for our consumption, only that we don’t have the technology to harvest the energy.  It contradicts with the view point of most environment people that we should simply use less energy.  I think the best way to solve the energy problem is through technology.  You can never solve the problem by conservation, it can only buy you some more time until the technology is ready.  Some people challenge the 1% number and accuse me posting misleading information.  I don’t know how the number is arrived, so I decide to work out the math myself to prove I am right.  After some research, here is the math:

US has 938 million acres of farmland (from US Dept of Agriculture website)
US use 138 billion gallon gas per year (from US Energy Statistic)
The highest efficiency of biofuel production is 15000 gallon per acre (from Wiki entry on Biofuel )
938m * 1 % * 15000 = 140.7B > 138B

Therefore, if we can produce biofuel with the most efficiency future technology, we will only need 1% of US farmland to produce enough gas for all the cars in US.  With the best technology today, we can only produce 1000 gallon per acre.  (BTW, grains, corn or soybean’s efficient is less than 200 gallon per acre.)  Biofuel is a pretty new technology, there are lots of room for improvement.  If it can follow the pattern of the Moore’s Law, 15 fold increase in a few decades is totaly feasible, at least according to the theory.