I bought a diesel Ford Fiesta 1.4 TDCi 4 years ago with the intention of using biodiesel. Ford only allow 5% biodiesel under their warranty, so it was a slow start. Even slower due to the lack of nearby outlets to buy the stuff 
. However, now that my car is out of warranty, I’ve signed up with a local organisation CambridgeBiodiesel who supply up to 100% biodiesel. Current price is comparable with regular pump prices, although there are/will be some additional set-up costs. Hopefully the government will continue it’s glacial progress towards reducing fuel duty for bio fuels…
I kept a record of the fuel efficiency of the vehicle during most of it’s current life using mineral diesel (using a cheap but pretty basic mobile phone app). All I do is record the odometer reading and amount/cost of fuel bought each time. The general conclusion so far is that I’m getting about 5 l/100km (or about 47mpg) combined urban/extra-urban. This doesn’t compare well to the Ford spec of around 67mpg combined! No doubt it’s my driving style… (nothing to do with the ultra-conservative simulated driving style of official testing).
One of my current problems is getting the biodiesel into the vehicle. It arrived in two 25 liter screw-top drums of 50% mix, which are quite heavy to shift around. I got a siphon, which works OK at getting the stuff into the tank – my problem is that getting to the organisations pump is tricky, hence current arrangement.
I’ll update the info here in a few months when I’ve a reasonable set of fuel economy data.
Current thoughts though are that the fuel system (either the pump or other) is struggling slightly with the increase in viscosity. It’s fairly cold at the moment (-2 to 5 C) which magnifies the effect. Symptoms being slightly longer crank to start and intermittent judder at low speed – using mineral diesel the engine when warm will happily chug along at 30mph in 5th but it’s not always so smooth with the approx 50% biodiesel.
johnkazer said
Now it’s a bit colder, my car is starting to noticeably struggle when cranking the engine. Rather than starting immediately on turning the ignition key, it requires the ignition to be on for 3 – 4 seconds before reliably starting. The dawn temperature today was about 2 C – I wonder if it’ll actually start once it’s below freezing…?
Once running though I didn’t notice any particular issues. I certainly wouldn’t feel comfortable putting in a higher percentage of biodiesel and 50% was the limit recommended by Cambridge Biodiesel.
johnkazer said
Well, now it’s freezing (about -2 C) and the car still starts after a couple or so seconds cranking the engine. Once going it’s still just fine though
Horia Popa said
Nice job. I own a ford focus 1.6 TDCi and in the manual is says that I cannot use more than 5% biodiesel. Since you have used it with success I don’t see any reason for me not to do so. Shouldn’t the biodiesel be cheaper than regular fuel? You said that the car doesn’t start as fast since you’re using biodiesel. Why?
johnkazer said
Well, your warranty will likely be void if you use a higher blend than the manual stipulates. Of course, if like mine your warranty has expired then no problem!
Biodiesel itself is in theory cheaper (partly because the duty is less) but a) it’s 50% so someone still has to buy the regular diesel but also because there are no economies of scale – it’s usually small operations (such as Cambridge Biodiesel) that are handling and selling the stuff.
My car doesn’t start as fast (when sub 2 – 4 degC) because biodiesel is slightly more viscous than regular diesel at that temperature – the fuel pump has to work a bit harder and apparently the Fiesta ones are particularly puny.
Do a Google or other search for “biodiesel forum” – these often have info from drivers of specific models.
Measuring my car’s mpg - Ford Fiesta Finesse, 1.4 TDCi « RealGreen said
[...] January 30, 2007 at 10:18 pm · Filed under Biofuels, Life style, Car [Also see my earlier post] [...]