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  • Posted July 20th, 2017

    One man’s journey from diesel to veg oil

    One man’s journey from diesel to veg oil

    This week Lowimpact.org met Geoff, a.k.a the Veg Oil Guy, who runs two websites and a YouTube channel chronicling his exploration of diesel to vegetable oil conversion and proving veg oil motoring can be done!

    First things first. What was it that inspired you to make the switch to vegetable oil? Where and when did you learn about it and what was your first reaction?

    I’m a big guy, so I don’t easily squeeze into the seats of most cars, but the Toyota Landcruiser I bought roughly 10 years ago was incredibly spacious. However, I didn’t enjoy the bad press and harsh tones of those that labelled me an environmental vandal and ‘Gas Guzzler.’ Plus, much more importantly, I didn’t feel good about a vehicle that only managed 24 miles to a gallon of diesel. So rather than rush out and buy a tin opener and a Prius, I decided to see if there was a way of reducing my polluting problems.

    I’d already heard about biodiesel a while before and so a couple of books later I was madly experimenting in my garden shed. But the chemicals involved are not just nasty, they’re downright dangerous. We’re talking about off-gases that you can’t smell but which can kill you and alkalines that burn without pain (allegedly) as they kill the nerve endings. As I had a toddler happily ambling around at the time, I quickly abandoned this pursuit.

    Whilst researching further on the internet, I came across a company called DieselVeg (they don’t exist anymore – shame really). I remember reading something along the lines of “why mess about with deadly chemicals in biodiesel when ordinary vegetable oil does the same thing?” This was one of those “what?!” moments that we all occasionally have, a mixture of fascination, disbelief, excitement and suspicion.

    I learned that Rudolf Diesel created his engine in 1892 to run on some kind of plant oil (peanut oil is the most cited, though no one knows for sure). It seems even back then petrol was expensive – gasp – and he had the vision of third world economies beneficially producing crops for conversion to oil for vehicle use. What he probably wouldn’t have realised was that using vegetable oil in a combustion engine produces far less emissions and is effectively carbon neutral. Like most people hearing this for the first time, I was astounded. Quite why the diesel engine didn’t continue down the road of organic fuel is lost amongst the typical inaccuracies, conspiracies and outright lies on the internet and I’ve never researched further, but it seems the efficiencies of the diesel engine were recognised (oh yes, in terms of mechanical efficiency, the diesel is still superior to petrol) and a petroleum based fuel was created, which is what we think of as ‘diesel’ today.

    Veg oil conversion engine view
    A view of Geoff’s converted engine.

    What was the veg oil conversion process like and is it available today if others are interested? Are there any conditions to be met in terms of vehicle requirements?

    Please understand I’m no expert – just an end user. I can only express my limited knowledge and experience which could be wrong.

    In terms of restrictions, as I understand them, the most obvious is that only diesel engines can run on vegetable oil, not petrol engines. Another is age: the older the diesel engine the more likely it is that conversion is possible. Newer diesel engines are much more sophisticated and the simpler engineering like that found in older models is more ideal. I certainly couldn’t tell you which type of vehicle could or could not run on veg oil, but a very rough guide and guess would be anything less than 10 years old probably won’t manage it, but it’s certainly worth checking with a professional fitter in case I’m wrong.

    In terms of mileage, as a nice warm engine is ideally required veg oil is better suited to long journeys. Again, because a warm engine is required and more critically because veg oil thickens at lower temperatures, a warm climate is ideal. A moderate climate like that in the UK is manageable and as for colder climates, well, even regular diesel freezes in cold climates.

    The conversion process for me was carried out by a company called DieselVeg who regrettably no longer trade. Fortunately there are other companies providing a similar service and some will even sell you a kit – if you’re handy with spanners. I keep a list of those I’m aware of on my website. There are probably many more companies that I’m unaware of and if they want to be listed they should get in touch with me – I don’t charge for this, it’s just for information.

    When it comes to converting to a two-tank system, the conversion process itself involves fitting a second fuel tank (hence the term “two-tank system”), a fuel heater, some filters and a switch. The second tank tends to be small and usually housed inside the boot or hatch. The rest of the equipment is installed in the engine bay with a switch on the dashboard. When completed by professionals, it just takes a few hours. It’s no different to a full service or similar.

    What is the day to day process of running a veg oil motor? What are the benefits and drawbacks?

    Diesel engines and cold vegetable oil don’t mix. It’s literally a sticky situation. Cold veg oil is gloopy and viscous but when the oil is hot, it’s far more liquid – think of oil in a chip pan. Because of this, cold engines don’t start well on cold veg oil and have to be started using ordinary diesel. The engine is then run for several minutes or miles until it reaches the ideal temperature. At that point the diesel is seamlessly phased out and the veg oil is phased in.

    Now the veg oil motoring begins and you can’t tell the difference in honesty – unless you’re sniffing the exhaust pipe, which is never a good idea. Some claim better mpg, some claim reduced engine noise, but I’ve never noticed either. Just as the engine has to be started on diesel, it also has to be turned off whilst running on diesel so there’s diesel in the pipes ready to start the next journey. This leads me neatly to drawbacks…

    You MUST remember to switch back to diesel at the end of each journey and that has to be the biggest drawback – remembering that small, simple but unfortunately manual act. But we’re human and we do forget, and when that happens it can take a lot of time and effort to coax a cold engine full of veg oil into life. It can even be damaging to the engine. You’ve been warned! Because of this warm up / cool off process, veg oil motoring is better suited to high mileage driving. If you’re just popping to the local shops, it’s too impractical. But if you’re doing longer journeys, it really comes into its own. I’ve travelled the length of the country on less than a gallon of diesel before now.

    Probably the next major drawback is weight. Pulling onto the forecourt and filling up with 40 litres or so is child’s play. But when you’ve got to manually carry that amount of liquid and carefully pour it into your vehicle, it’s quite a different matter. As my vehicle takes 70 litres, it’s a lot of heavy hauling and not something for the physically less able. I’ve actually discouraged a few disabled drivers from seeking conversion for this very reason – there’s no UK veg oil forecourts that I’m aware of, though I believe they exist in parts of Europe.

    The next major drawback is also the biggest bonus – the use of WASTE vegetable oil. It’s possible to be given used oil freely by restaurants and other commercial outlets as to them it’s a waste product. This potentially means FREE FUEL. However, filtration is a must and this can be a messy process – very messy sometimes. Think in terms of fatty gunge. Not nice.

    Veg oil conversion filtration system
    Geoff’s home veg oil filtration system.

    We’ve been suitably warned! So has your interest in veg oil motoring led you towards any other endeavours?

    Veg oil motoring and veg oil itself has become quite an important part of my life. Some years back in an effort to help spread the good word of veg oil motoring, I created my website as a free source of information and advice on the subject. I regularly get questions from all over the world and am pleased to think – even if it’s only in a small way – I’m helping others and the environment.

    A couple of years ago now I gave in to requests to put myself on YouTube under the persona VegOilGuy. Having the perfect face for radio, I chose to narrate rather than star in my videos and a lot of experiences are recorded online for folks to watch.

    In my efforts to capitalise on free waste veg oil, I’ve developed a number of easy filtration techniques and become classed by others (but not by myself, I hasten to add) as something of an expert. My filtration systems are on my website and YouTube channel and I’ve been delighted by the wonderful comments received. I’ve had a number of university engineering students make use of my filtration systems for various ‘green’ projects and only a few days ago I was contacted by someone in the Bahamas. This person was using my filter system to take waste oil straight from a restaurant to power a diesel generator.

    My YouTube channel has expanded somewhat as have my interests, which are varied, and I even developed a waste oil burner to power a homemade foundry to melt soda cans and other scrap metals for recycling into other projects. Right now I’m building a radio controlled lawn mower… yes, that’s not very environmentally friendly, but many of the parts were forged myself from recycled materials and I’m already scheming up ways to power it by greener methods… time will tell on that one.

    If any of our readers were interested in making the switch what advice would you offer them? Who could they go to and what kind of vehicle would they need to have?

    Running a vehicle on veg oil is not an easy option. You’ll be giving up the convenience of the forecourt in favour of hauling heavy containers. You’ll be restricted on your choice of vehicle (must be diesel and probably quite old) and you might find a small rise in your vehicle insurance (it’s classed as an engine modification – shocking that insurance companies would want to make you pay extra, I know).

    But if you can manage it, you can cruise along with the best knowing that your vehicle is spitting out far less pollutants than Mr Average. I would guess only electric cars can beat veg oil motoring when it comes to emissions (depending on how they source their electricity of course). You can benefit from free fuel if you can acquire it (though some duty may be payable if you use too much – yes, the tax man wants a cut) and you can be proud of making use of a waste product that would otherwise be dumped. Even if you get your oil from the supermarket, you’ll know its carbon neutral and fully sustainable. There aren’t many drivers who can feel quite so smug behind the wheel.

    I would recommend anyone interested to research the subject thoroughly and contact a professional fitter.

    Would you ever turn back or are you a veg oil driver for life?

    I must confess I’m not doing the mileage I once was so I don’t get to use veg oil like I used to. This hurts as it effects my pocket and the environment. My lofty goal right now, which fiscal restrictions are unlikely to allow to fruition, is to take a solid British classic – something like a Landrover Defender – and convert it to fully electric. This would give me a large vehicle that I could drive moderate distances on minimum emissions. And whilst buying a small electric vehicle would likely be cheaper, it wouldn’t be anywhere near as much fun!

    So I think veg oil is always going to be an important part of my life, but unless circumstances change I don’t think I’d class myself as a true veg oil motorist – though I encourage those doing the mileage to try it. The benefits are too great not to!

    Thanks for sharing your veg oil conversion journey, Geoff. We hope others will be inspired to consider making the switch too!

    VegOilCar is the place to go for Geoff’s veg oil motoring advice whilst you can find out more about his numerous projects, with tutorials, on the VegOilGuy website. His dedicated YouTube channel, meanwhile, can be found here.

    The views expressed in our blog are those of the author and not necessarily lowimpact.org's

    1 Comment

    • 1Andrew Rollinson July 31st, 2017

      This seems a very good in many ways. I would like to know more about why newer diesel engines can’t be converted and a list of which engines could/could not be used.

      I can’t see why vegetable oil couldn’t be used instead of fuel oil for domestic heating in rural areas which are off the mains gas system. This would seem a better application as there would be no less of efficiency that you get with a vehicle carrying the extra weight of two fuel tanks. And as these are just burners, I don’t expect that filtering would be required as much.

      Having worked with vegetable oil as a fuel a long time ago, you never seem to be able to get the smell off your hands! A minor inconvenience of course!


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