Biodiesel - Anybody with experience?

[lady_brewer]

Hubby and I are looking to switch from a gas to a diesel, since we usually clock 1000km/wk on the car (625 m/week? Is my conversion wrong?). Could potentially pay for itself...

Recently heard about biodiesel... anybody with advice? Experience? Thoughts? The idea would be to get used oil from restaurants and mix with commercial diesel.

Looking at a used VW Jetta TDI (if possible)... and 2006 is available at a dealer as of now... otherwise probably need to buy new due to location and limited choice.

TIA for any input or opinions!

 

[FromZwolle]

i've read up on the subject, but have no $ to invest into it. to make your own biodiesel, you need to mix organic oils with sodium hydroxide and methonol/ethonol to separate out the glycerine. you also need to swap out the fuel lines with the low sulphur compatible lines. If you just want to use vegetable oil you need to get a SVO kit for the car and someone who can install it.

i don't know how handy you are, or how much time/effort you want to invest, but check out oilgae.com and http://www.journeytoforever.org/biodiesel_make.html

i'd try to find out if there is a biodeisel vendor in your area before you invest any money in a vehicle. making your own fuel might save $, but it will invariably take large amounts of time and effort.

 

[HairyDogBrewing]

Late model cars can run biodeisel, older cars have rubber seals that will dissolve.

I made some small batches as an experiment.
For each liter of oil you need about 5g of NaOH lye and 200ml of methanol.
You can also use KOH and ethanol.
The methanol must be 99% because water interferes with the reaction.

The mixture has to be kept warm until the conversion is complete, then separate the biodeisel from the glycerin byproduct.
About 150ml of glycerin is created per liter and it's a pain to get rid of.
The biodeisel is then washed to remove impurities and heated to remove water.
So you also generate 2 or 3 liters of dirty water.

 

[jbford]

yes...

A my ex-employer makes it. not easy to do right and lots of waste. They sometimes buy up material that start-up's have F'd up and rework it into good stuff. You can't easily beat the price of diesel without the federal subsidy. Used oil does not work well, it has been altered by the heat and is full of crud u have to filter out. Biodiesel gels in below freezing weather unless expensive or modified oils are used.

If you just talking about mixing the raw oil with diesel, don't do it.

 

[lady_brewer]

Thanks for the info and the links... will definitely look it all over. Don't think that there is a place locally that I can get biodiesel, certainly would want to do it right, but it does sound like it might be a good bit more work that first thought.

The mechanics and modification might not be too hard... hubby is a marine diesel mechanic and currently doing his work term in a show with at least one VW mechanic (who actually does run his car off of some form of biodiesel... which is where the whole idea came from.)

Definitely going diesel anyway, since it will still cut our monthly fuel cost in half, and we have to get a new car either way.

 

[david_42]

Another alternative is to add a SWO (straight waste oil) system.

Main advantage: you only have to filter the waste oil, not convert it.

Main disadvantage: It gells at moderate temperatures and you have to pre-heat it. This means you need to retain the original diesel system to get the engine going and before stopping to keep the lines open.

Gripping hand: Got a source of waste oil? It ain't free these days.

Bottom line: not worth the trouble. B99 is about a buck a gallon more expensive around here and that is with the $42/barrel federal subsidy, so it's really $2/gallon more expensive.

 

[SpanishCastleAle]

A guy at work has gone down this path and just uses the SWO. He used to make biodiesel but says this is much easier. He goes around to restaurants and collects the oil. I give him a gallon every few months.

 

[Homercidal]

Last time I looked at using waste cooking oil the van had to filter the oil (more than once) and then preheat it.

The concept worked, roughly, but the team had to constantly fight to make it work. I've heard of others having better success since that time, but I have not looked into it again.

Cool process, but when everyone starts wanting to do this, then the oil will stop being cheap.