PeachParts Mercedes-Benz Forum - View Single Post - Disadvantages of Waste Vegetable Oil???????

rwthomas1 · #3 02-18-2005, 06:12 PM

There is no free lunch!

Here are the issues:

Petro diesel = expensive but very easy, the lazy "rich" mans option.

WVO conversions (heated systems) = cheap, really cheap if you have the time and space to collect oil, filter it, and can deal with loosing some truck or storage room. WVO systems can cut your fuel expenditures by 90% but this doesn't take into account your time. Not the best for short trips as the system never heats up and you are constantly cycling the purge system. The best system for those who commute and run the engine for at least 10 minutes.

Biodiesel = about halfway in cost between Petro and WVO. You still have to collect oil, filter it, and either buy or build a processor. Obviously this takes time. Biodiesel proponents claim it takes no longer to make it that to filter WVO and its not an issue. You do however need the space for a processor and to be able to store methanol, lye and well as dispose of the byproduct glycerin. Biodiesel will eat older rubber parts over time but it seems this happens fairly slowly and the parts can be replaced with upgraded materials when this happens. Biodiesel is the better choice for short trips, etc. You have to be careful in cold climates to keep it from gelling but there are additives to help deal with it.

Blends = cost depends on how much you use. Some have reported no trouble running blends but there have been reports of injector coking and other problems especially with high concentrations. You would still have to collect and filter WVO. A possible solution would be to install a coolant type fuel heater to assist in burning the blended fuel. Obviously this won't help on cold startup but it will minimize the coking issues once the engine warms up.

So, there you have it. IMHO most people are lazy and while they may complain about the cost of fuel they aren't motivated enough to do anything about it. I have been trying to get the WVO system put together in my truck for a while now but I am just too busy. By summer I should have it running. I use $2500 of fuel a year so cutting my costs by 90% would be significant. RT