Two big steps forward were taken this week in using a biofuel blend to power commercial airline flights.
United Airlines flew from Houston to Chicago with jet fuel made from algae, and Alaska Airlines says it will make 75 biofuel-powered flights this month.
Analysts say biofuel could eventually lead to better fuel price controls for the airlines, but not quite yet.
Alaska Airlines paid $16 a gallon for the biofuel compared to $3.15 for a gallon of jet fuel.
The hope is that the price tag will come down as refining technology improves.