B10

B10 is a fuel blend containing 90 percent mineral diesel and 10 percent biodiesel by volume. Biodiesel is a fatty acid methyl ester (FAME) typically derived from vegetable oils, animal fats, or recycled cooking oil. The blend sits in the middle ground between pure fossil diesel (B0) and higher biodiesel concentrations, offering modest environmental benefit without requiring engine modifications on most modern diesel vehicles.

The "B" designation comes from biodiesel; the number indicates the percentage by volume. B10 is the standard fuel grade now mandated or recommended in the European Union, United Kingdom, and several other regions. It meets EN 590 specifications in Europe and equivalent standards elsewhere. The 10 percent threshold represents a practical limit: most diesel engines manufactured after the mid-2000s can tolerate B10 without material wear or performance loss, though some older engines and equipment may show compatibility issues.

B10 performs almost identically to pure diesel in terms of energy content, combustion temperature, and engine power output. Cetane number (ignition quality) remains high enough for cold starting in most climates. However, biodiesel absorbs water more readily than mineral diesel, so B10 requires careful storage and can develop microbial growth in tanks if water contamination occurs. Injector deposits and fuel filter clogging are rare but possible, particularly if older fuel sediment dislodges from tank walls after the first introduction to B10.

Compatibility considerations matter in practice. Agricultural and construction equipment, marine engines, and older light-duty diesel vehicles may carry warranty exclusions for B10 use; manufacturer guidance is essential before switching. Fuel lines and seals in pre-2000s vehicles sometimes degrade under higher biodiesel concentrations, though B10 seldom causes visible problems. Cold-flow properties degrade slightly compared to B0, so winter additives become more important in northern climates.

B10 represents a regulatory middle path: it reduces transport sector carbon emissions and fossil fuel dependence without imposing costly fleet retrofits. Higher blends like B20 or B100 require engine tuning, emissions modifications, and hardware durability testing. B10 avoids this friction while maintaining fuel supply continuity through existing distribution networks. From a trade perspective, B10 adoption has been absorbed into standard diesel supply chains across most developed markets since the early 2010s.