Biodiesel, SVO and WVO

Posted By on March 8, 2006

Tank Switch
A friend of mine spotted this switch on one of the forums he visits, and I thought was worth a post. Actually it segues into a pet peeve of mine, that of people confusing the ‘no conversion biodiesel’ alternative with just ‘straight’ (SVO) or ‘waste’ (WVO) conversions.

A quick comparison between what I call biodiesel and SVO/WVO is that biodiesel is vegetable oil that has undergone a transesterification process where glycerin is removed. Using this alternative fuel requires no modification on most modern diesel vehicles. It can be used at 100% (‘neat’ or B100) or blended with petroleum diesel at any percentage. A common 20% blend is called B20. It is included as an alternative in the recent energy legislation and is eligible for tax credits. There is a growing commercial industry around Biodiesel (see as well as many grassroots organizations.

SVO or WVO ‘conversions (the switch photo) is an alternative to petroleum that requires additional hardware be installed into cars and trucks. Most options install a separate heated tank where the vehicle starts on regular diesel or biodiesel and then switches to the SVO or filtered WVO after it has been thinned by heating. Additional heating of fuel lines and filters are generally installed too. Shutdown requires purging of the fuel line and running a fuel that doesn’t thicken when cooled for a few minutes. Two installation kits that I’ve tinkered with are Greasecar or Greasel.

I hope this helps … yet many in the media continue blend the terms. Correct them!


Desultory - des-uhl-tawr-ee, -tohr-ee

  1. lacking in consistency, constancy, or visible order, disconnected; fitful: desultory conversation.
  2. digressing from or unconnected with the main subject; random: a desultory remark.