At the core of your fleet lie your engines. If they run well, your fleet runs well, and a key contributor to their performance is fuel. But not all fuels are crafted the same – and not every fuel will suit every engine. So, what makes them different, and how can you tell if you’re getting the right fuel that fits your fleet?
Consider a cup of coffee. It gives people a boost of energy in the morning that for many has become routine. But not all coffee is prepared the same. Different water temperatures, filter type and even pressure during the brewing process can change mere coffee into the perfect cup.
The same applies to fuel. It’s easy to get caught up in fuel’s function alone, but do we pay enough attention to how it treats our engines? The difference between a passable fuel vs a good quality fuel means a better-running engine and an optimised performance for drivers. The result is an efficient fleet that keeps costs low and returns high for your business.
Fuel and its ‘fit’ for an engine
Two key parts of a diesel engine are a fixed cylinder and a moving piston. The engine works beginning with air compression in the cylinder. The vehicle’s computer sends a signal for the air to be sprayed with fuel at a measured rate, the piston compresses the mixture and the mixture ignites. This burning – or internal combustion – is a chemical process that releases energy from a combination of fuel and air. The expanding gases from combustion push the piston, which then drives the powertrain that in turn moves the vehicle’s wheels.
Variation on that basic process is what can make a difference in the optimisation of an engine. You may witness this difference on a long drive. A fuel with higher density can provide an improvement in fuel economy due to the higher energy content per litre of fuel.
But a dense fuel does not always mean a better ride: an overly dense fuel could potentially result in a lower cetane number, which can impact cold start ability of the engine.
This is just one example of a fuel quality that can affect engine performance. A high-quality fuel balances fuel density in relation to other fuel dimensions for optimised combustion and vehicle operation.
Factors affecting fuel performance may also occur from issues that arise between fuel production and delivery. For example, improper storage along the supply chain may lead to increased water in the tanks from condensation or environmental conditions like rain, which can contribute to microbiological growth at the fuel-water interface. These microbes may produce acids which make the fuel corrosive to an engine or other parts of a fuel system. In addition, microbiological growth can lead to filter plugging. Over time, this can hurt performance and result in more instances of vehicle maintenance.
Proper storage and maintenance procedures are critical to reducing water contamination and propensity for microbiological growth.
Understanding your fuel
There are multiple ways to gain an indication of how a fuel can deliver at scale and in the long run for your particular set of needs. To meet buy-sell agreements or any existing government regulations, the quality of fuels are typically tested and reported in a Certificate of Quality (COQ), which reflects the acceptable range for the agreements or government standards for that particular fuel. The COQ may contain information about the fuel’s makeup, including water content, fuel density and CFPP.
However, the COQ only covers the fuel at the time of production. The reality is more complex. A lot can happen during the long process between production and delivery, which is why it’s important to ensure that your vehicles are receiving fuel from a high quality fuel supplier, with reputable experience in supply chain management.