BioDiesel?

Updated: May 3

Three things led to me investigating bio diesel:

  1. The IWA Sustainable Boating Group recommended adoption of bio diesel fuel

  2. Ortomarine asked if I had considered a biodiesel generator, and

  3. I wondered what would be involved in using bio diesel for Perseverance.

My investigations led to some unexpected conclusions and (spoiler alert) all will be revealed on 29th May…


First Generation BioDiesel

When I started out, I thought bio diesel was just one thing, but I rapidly learned that life isn’t that simple. The “first generation” fuel is FAME (Fatty Acid Methyl Ester) which is produced from vegetable oils, animal fats or waste cooking oils.


Trip down memory lane for us oldies. Sorry, couldn’t resist.


FAME is the most widely available type of biodiesel and is often blended with regular diesel. The concentrations in use are 7% FAME, referred to as B7, 20% or B20 and FAME by itself is B100. If you go to the pumps and fill up your car with diesel, it is already B7, as this concentration is OK to run in any engine. Many, but not all, engines can use B20 and many large operators (e.g. coach and haulage companies) who have engines which can run, or be modified to run, on B100.


To reach net zero goals, B20 can only be an interim step. B100 must be the way to go. Unfortunately, the “way to go” goes rapidly downhill. B100 only has a 3 month shelf life, so if you plan to leave your boat for a period, you would have to drain the tank. It is more prone to water and diesel bug contamination than normal diesel and it can rot seals. On top of all this, its viscocity increases at low temperatures, making it unusable on very cold days. One amusing anecdote, that a bio fuel supplier told me, was of a coach company in Scotland who had to modify and de-modify their engines each year, so they could use bio diesel in warm weather and normal diesel in the winter months.


Determined not to be put off by such trivia, I looked for a generator which could use B100. After much research (Google really is my friend) I found two manufacturers.


The first manufacturer advertised a “Bio-Diesel Generator” based on the Austrian Deutz engines, but since Brexit, these are no longer available. Also, their smallest generator was far too big for our application.



The second manufacturer was Lister Petter. The same Lister as famed for slow turning narrowboat engines of yesteryear. They make an entirely suitable generator of the right size that is certified to run on B100 fuel. It has all the right characteristics, except one. It does not meet the emission standards required by Directive 2013/53/EU. This EU Recreational Craft Directive sets standards for diesel emissions which rule this engine out completely. I asked if there were any prospects of meeting the regulations in future, but Lister Petter told me this would be too expensive. So near and yet so far.


My conclusions about FAME B100:

It is a highly unsuitable fuel for recreational craft

No engines meet the emissions regulations and are approved to use B100.


As an aside, I checked 14 different manufacturers of narrowboat diesel engines, and while some could accept B20, none was certified to run on B100, so these conclusions are applicable to both direct diesel power and hybrid systems.



Second and Third Generation Bio Fuels

There are many different fuels becoming available, including the splendidly named Fischer-Tropsch Biodiesel, but the only one that is becoming available commercially in the UK is HVO (Hydrotreated Vegetable Oil).


Unsubtle plug for helpful company, with link to HVO FAQ for more details..


Now we get some really good news. HVO is a drop-in fuel which means that you can put it in the same tank as conventional diesel and it will mix and run without problems. The engines don’t need any alteration and IWA advise that it has been approved for use by all diesels currently in use on the canals. And it gets better – HVO has a ten year shelf life, does not grow diesel bug, does not damage seals and will keep working at low temperatures.


Before you rush off to buy some, there are a couple of things to be aware of. At present, it is only available in London between Wembley, Bow back waters and Waltham Cross.


Alternatively, you can get a delivery of 5,000 litres direct from the suppliers, but only if you have a big enough tank!!! For proving exercises, smaller 205 litre barrels are available, but the suppliers will not repeatedly supply these small barrels.


A second issue is that HVO is more expensive than normal diesel. I was told “about 70p/litre for HVO” (compared with 53p/L for red diesel at the time of writing). On top of this, the calorific value is a little lower than normal diesel and it has a slightly lower density, so the energy in a litre of HVO is about 7.5% less than in a litre of old-fashioned diesel.


Let's Try HVO

All of the above is conjecture, research and analysis. The proof is, as they say, in the pudding. Or in this case, on the cut.


A short digression, but we'll get back to HVO soon. The good people at Ortomarine (unashamed promotion for my excellent boat builder coming up)...

... realised that they have built three serial hybrid boats with different systems and they could be compared against each other on a day's cruise. The idea of a comparative trial was born, which swiftly became known as the Wacky Races.

As Perseverance is built for silent gliding down the canal, perhaps Penelope Pitstop is more appropriate than Dick Dastardly and Muttley.

The idea grew and fleet for the Wacky Races is now up to eight narrowboats, with three serial hybrids, two parallel hybrids and three conventional diesel boats. Comparisons of all the types of propulsion are now possible.


Back to HVO. Of the conventional diesel boats in the wacky races fleet, two are the same length, from the same builder with the same type of engine. This pair offer an opportunity to compare two fuels and Crown Oil have agreed to supply HVO for one boat so that we can compare its performance with normal diesel.


The fleet will cruise from Worcester to Droitwich on 29th May, and as most of the locks are broad, the two boats running the HVO comparison will cruise the route side by side, lock by lock, keeping the same speed to minimize differences. Think Torvill and Dean.


It is unlikely that there will be any engine handling differences (but any coughing, spluttering or failure to start will, of course, be noted) so the difference in fuel used will be the key measurement. If the theory is correct, the HVO boat should use a little more than the convenional fuel boat, but watch this space…


Summary

Let me bring the threads of this blog together.


I cannot see first generation FAME biofuel arriving on the canals because it is highly unsuitable as a fuel and the only engine that I found which is approved to use it, does not meet the emissions regulations.


HVO appears to be an ideal fuel, and I expect the Ortomarine trial on 29th May to confirm this.

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