One million gallons a day is a lot of oil. According to estimates late last week, that could be the daily rate of oil escaping from the Deepwater Horizon well in the Gulf of Mexico.
To put that number in perspective, we decided to look at what it would take to compensate just for the lost gasoline. We asked, How many Toyota Prius hybrids would you need to sell to offset the loss?
Turns out you'd have to sell almost 1 million Priuses globally to conserve enough gasoline to offset the amount wasted as the escaping oil pours into the oceans and fouls the beaches.
Here's how the math works.
An oil-industry expert who asked to remain anonymous told us one gallon of unrefined light crude, the kind the Deepwater Horizon produced, provides half a gallon of gasoline, or perhaps a little more.
So that's 500,000 gallons a day we need to save.
If the average U.S. car drives 10,000 miles a year at 25 miles per gallon (to make the math easy), then the 50-MPG 2010 Toyota Prius saves 200 gallons of gasoline per year. Or 0.55 gallons per day.
So you'd have to sell 912,500 Priuses--each of them saving a little over half a gallon of gasoline a day--to offset the loss of half a million gallons every day.
But Toyota doesn't make anything close to that number of hybrids right now. In fact, in 2009, Toyota sold 139,682 Priuses in the United States, out of a total of 173,655 hybrids (plus 21,890 more from its Lexus luxury line).
Until the end of this year, its total annual hybrid production is capped at 500,000 by constraints in the supply of nickel-metal-hydride battery packs used by hybrid cars to store energy.
The oil flow estimate comes from the Washington Post, by the way. It reports that the latest estimates suggest that if the flow has been roughly consistent since the blowout on April 20, the well has leaked about 53.6 million to 64.3 million gallons of oil--or up to 1 million gallons per day, far lower than earlier estimates by BP and the U.S. government.