Sunday, September 11, 2011

The gas station pumps energy at ~22 Megawatts

Gasoline pumps in america pump no faster than 10 gallons per minute [source].
Gasoline has an energy density of ~35 megajoules per liter.
[wiki quoted source (I have not double checked it)].
Therefore the power with which the gasoline pump transfers potential energy into your tank is:
(34.8 (megajoules / liter)) * ((10 US gallons) / (1 minute)) = 21.96 megawatts
For comparison, a typical circuit in your house can output a maximum of about 2,400 watts, or 0.0024 megawatts ... you would need almost 10 thousand household circuits to get the potential energy flowing into your electric car at the same rate. Of course no battery yet exist that can swallow up that energy so fast --- and you certainly couldn't store it for a week and then take it with you 100 miles down the road.


  1. I was going to post a comment, but instead I think I'll post write a reply as a post on Thursday.

  2. There's a lot of problems with that model, though. For example, say you have a bad/damaged battery and you go to swap it out. You get a shiny new one, and some other person gets stuck with it. Around and around it goes, and the person who ultimately gets screwed is not likely the one who broke it.