Full test data is available on request (info@gbf.ltd) and all statements are factual from recognised test procedures.
To get into the details however, we’ll break this down into regulated emissions (NOx, CO, HC, PM) and unregulated emissions (chiefly CO₂).
GD+ HVO uses the same source material as biodiesel – vegetable oils, fats, used oils. Biodiesel production involves removing part of the molecule (glycerol) and swapping it with methanol (wood alcohol). This produces FAME – fatty acid methyl ester and glycerol -hence the glut in glycerol. FAME is similar to diesel and has been used as a partial substitute for diesel (currently around 7% of diesel). The plans originally were to replace even more diesel with FAME. Biodiesel (FAME)’s greatest credential is that the carbon backbone comes from atmospheric carbon dioxide and not from fossil fuels. Plants are unique in their ability to convert atmospheric carbon dioxide, through photosynthesis, into useful organic molecules, including vegetable oils (meaning oils extracted from seeds of plants - sunflower, palm, rape etc.).
However many Original Equipment Manufacturers (OEMs) are not too fond of biodiesel (FAME) – why?
The problem with FAME or biodiesel is that it retains the carbon – carbon double bonds – the unsaturated bonds which are found around the middle of the 16-18 long carbon chain. They are prone to reaction with oxygen which causes all sorts of problems, varnish formation, thickening of the lubricant etc.
GD+ is a clever solution to these limitations – the same vegetable raw materials used to make biodiesel are used to make hydrotreated vegetable oil (HVO). The oils are reacted in such a way that no double bonds are left and the molecule is isomerised (rearranged lego-wise to make the structure linear) to make more effective molecules. No glycerol is produced. The molecule resembles the ideal diesel molecule – there’s no sulphur, no aromatics and no double bonds. Unlike biodiesel you can replace 100% of diesel with this fuel. It’s a pure aliphatic hydrocarbon which burns cleanly. All the carbon in the molecule comes from atmospheric CO₂.Hence there’s a 90% reduction in CO₂ emissions associated with GD+ HVO, which is the Greenhouse Gas saving. The CO₂ is taken from the atmosphere by the vegetable growth process and returned on combustion. In the case of GD+ (Whereas in the case of diesel, it is extracted from fossil fuels and on combustion contributes an augmentation of atmospheric CO₂). The remaining 10% is due to the energy expended in growth, harvesting and processing of the material. In addition to the CO₂ reductions of around 90% this fuel is formulated to reduce the regulated emissions when compared directly to diesel fuel in diesel engines. The reductions in NOx, PM, CO by HVO based fuels is well documented and accepted. With this in mind, cutting emissions in pollutants by 90% seems a modest claim.
