Waste Vegetable Oil (WVO) questions

I am interested in WVO as an alternative fuel, and am aware of its limitations in terms of scale*, but I have some technical questions. I like the dual-fuel option of adding a separate tank for filtered WVO so that the otherwise unmodified vehicle still runs on diesel in case of WVO supply issues, but I don't like the idea of consuming diesel on a regular basis to get up to temperature if it can be helped.

What I'm wondering is this: if an unmodified diesel engine can be run on WVO thinned with a solvent (like mineral spirits or turpentine) without ill effect, couldn't I do two fuel tanks, one with filtered WVO and one with filtered WVO thinned with turpentine? This way, I can run the car/truck without any diesel at all except as a contingency, I don't have to buy as much solvent or mix as much fuel, etc.

Is this a feasible solution? A terrible idea? Has anyone tried it?

Related: could a dual-fuel solution work for a diesel generator?

*Specifically, that there is not enough for everyone to switch to it, that it is not "the" deeply sustainable answer. Heck, neither are tires, steel, or roads, for that matter. But those of us who can switch to WVO would do well to do so; and, likewise, those who can drive something smaller; who can drive slower; drive less; carpool; ride bikes; ride horses; walk. This thread is not intended to address the appropriateness of the technology, but to examine solutions to a technical question.

In a general answer I am going to say probably not for the average engine.  Combustion energy and flame front speed would need to match diesel and that would be tough to do reliably for the fuel as those change from batch to batch.    And you want no conversion time making it tougher still.  Most engine systems I am aware of doing dual fuel need a warm up time on diesel before converting and on the other end they have to  run on diesel for a while to flush the other fuel out of the injection system before shut down.  With care you can probably make it work but expect higher emissions and lower fuel efficiency and a lot of time adjusting your fuel mixture for each batch

Now is bio diesel on your possibles?  By processing it chemically you end up with a more consistent fuel.  In warm climates possible but in cold climates will still need warm up and cool down change over cycles or heaters in fuel system.

Now there are a few engines out there that are designed for dual fuel operation.  I know VW had one about 15 or 20 years ago that the electronics changed fuel delivery timing and injector pulse length so most fuel could be used.  Still needed heaters or system flush runs to change over from fuel that might be gelling cool.  Betting there are other specific engines available if you research

Hi Mason,
I'm assuming you are talking about Waste Vegetable Oil for any future readers who are not familiar with that acronym.

I know there are quite a few vehicles that are fitted with two tanks for the same kind of fuel... so the changing mechanism should be possible, but I would worry that the engine would need to be tweaked when going from one fuel to the other. But I'm not an engine guy, so I could be wrong.

Mason Berry wrote: I don't like the idea of consuming diesel on a regular basis to get up to temperature if it can be helped.

Could you expand on this statement a bit?  Why exactly don't you want to be consuming diesel on a regular basis?  Is it for cost reasons, or environmental concerns?  SHTF concerns?

Seems to me that wedding yourself to a chemical thinner like mineral spirits is going to make you more dependent on petroleum products like mineral spirits, so using a 1/4 gallon of petroleum diesel to make it work is not going to be either a financial, or an environmental issue?  

As is mentioned above, I think it's a more practical solution to make your own biodiesel than to start experimenting on what might be a very expensive engine to damage.  A repair man recently gave me some pointers to extend the life of my F350 engine.  That replacement could be 17k, so prevention is far, far cheaper.

Our next door neighbour used WVO for his ute.  He only passed it through a series of fine mesh strainers and let it settle.  Nothing else was required.  The problem that we have is that the regulations require oil to be collected by an authorised recycler. It does not need any additives as far as I know

If the non-WVO fuel is anticipated to sit in that second tank a long time, I wonder if it might not "last" as long as petroleum diesel and go bad on you...?

Paul Fookes wrote:Our next door neighbour used WVO for his ute.  He only passed it through a series of fine mesh strainers and let it settle.  Nothing else was required.  The problem that we have is that the regulations require oil to be collected by an authorised recycler. It does not need any additives as far as I know

Paul, what year was the ute made? I've heard of straight WVO working in (1) older diesel vehicles and (2) in climates sufficiently warm.

Michael Qulek, all of the reasons you listed are valid to me. Turpentine would be a plant-based thinner that would work from what I've read. I don't know, in two-tank systems, how often on average the startup fuel tank (typically straight diesel) needs to be refilled; assuming it isn't too often, the two-tank system would allow me to be totally diesel free while still freeing me from the commitment to processing all my WVO into biodiesel or something similar.

In terms of eco-friendliness (and this is all relative), I also have no idea whether the energy used in the manufacture of the extra parts would cancel out the energy "savings" of using a waste product as fuel.

Paul Fookes wrote:Our next door neighbour used WVO for his ute.  He only passed it through a series of fine mesh strainers and let it settle.  Nothing else was required.  The problem that we have is that the regulations require oil to be collected by an authorised recycler. It does not need any additives as far as I know

Hi Paul, just wondering what a 'ute' is?  Is it a utility vehicle?  I'm not even sure what kind of autos those are -- could you give me a hint?

Cheers,

-- Jojo