Cars Ok on Biodiesel

Biodiesel, in theory, can go into all diesel engines as the diesel engine itself was designed to run on plant oil.However it is the parts attached to the diesel engine which could potentially cause problems – although the vast majority of diesels on the road are fine running on 100% biodiesel.In reality, the rule of thumb is you can use 100% biodiesel in any diesel built between 1990-2004, but be aware that a one-off fuel filter change will be needed after you first make the transition (and any mix of biodiesel and fossil diesel is OK too).I would recommend that cars built after 2004 should run on a 50% blend not 100%.Be aware too that biodiesel made from waste cooking oil will freeze in winter and so from November to April one should blend that kind of Biodiesel at 50% as well.However, Biodiesel made from a Rapeseed crop (RME) will not freeze and can be used at 100% all year round in the UK.Please note that it is advisable to purchase biodiesel with EN14214 specification, that gives you some guarantee of quality.In short – to be safe, use RME Biodiesel at EN14214 in a car built between 1990 and 2004 and then you can be carbon neutral all year without problems!

In terms of official compatibility, despite the majority of diesel vehicles on the road being fine on 100%, only a handful of companies will officially approve their vehicles for 100% use.The companies that have approved 100% biodiesel are VW, Audi, SEAT and Skoda.They have approved all their cars built between 1996 and 2004 on 100% use of "RME" Biodiesel (Biodiesel made from Rapeseed) providing it meets the specification DIN41606 (which was later replaced by EN14214).These companies can still provide some brand new cars warranted on 100% biodiesel but one has to request it (best to get the official letter from German Base as some UK agents aren't fully aware).As these companies have officially approved 100% biodiesel I urge you to use your consumer power to support them in supporting the environmental movement.(e.g. Ask manufacturers directly via

Technical Details & Standards

There are three existing specification standards for diesel & Biodiesel fuels (EN590, DIN 51606 & EN14214).

EN590 (actually EN590:2000) describes the physical properties that all diesel fuel must meet if it is to be sold in the EU, Czech Republic, Iceland, Norway or Switzerland.It allows the blending of up to 5% Biodiesel with 'normal' DERV - a 95/5 mix.In some countries such as France, all diesel sold routinely contains this 95/5 mix.

DIN 51606 is a German standard for Biodiesel, is considered to be the highest standard currently existing, and is regarded by almost all vehicle manufacturers as evidence of compliance with the strictest standards for diesel fuels.The vast majority of Biodiesel produced commercially meets or exceeds this standard.

EN14214 EN14214 is the standard for biodiesel now having recently been finalized by the European Standards organisationCEN.It is broadly based on DIN 51606.


Criteria Derv (EN590) Biodiesel (DIN51606) Biodiesel (EN14214)
Density @ 15°C (g/cm³) 0.82-0.86 0.875-0.9 0.86-0.9
Viscosity @ 40°C (mm²/s) 2.0-4.5 3.5-5.0 3.5-5.0
Flashpoint(°C) >55 >110 >101
Sulphur (% mass) 0.20 <0.01 <0.01
Sulphated Ash (% mass) 0.01 <0.03 0.02
Water (mg/kg) 200 <300 <500
Carbon Residue (% weight) 0.30 <0.03 <0.03
Total Contamination (mg/kg) Unknown <20 <24
Copper Corrosion 3h/50°C Class 1 Class 1 Class 1
Cetane Number >45 >49 >51
Methanol (% mass) Unknown <0.3 <0.2
Ester Content (% mass) Unknown >96.5 >96.5
Monoglycides (% mass) Unknown <0.8 <0.8
Diglyceride (% mass) Unknown <0.4 <0.2
Tridlycende (% mass) Unknown <0.4 <0.4
Free Glycerol (% mass) Unknown <0.02 <0.02
Total Glycerol (% mass) Unknown <0.25 <0.25
Lodine Number Unknown <115 120
Phosphor (mg/kg) Unknown <10 <10
Alcaline Metals Na. K (mg/kg) Unknown <5 <5