More sustainable engine technology

TUNAP fuel additives to reduce LSPI

TUNAP Sustainability Report | Environmental | GRI: 302-4 | GRI: 305-7

More sustainable engine technology

Reduction of energy consumption (GRI 302-4 b: Fuel) and reduction of greenhouse gases (GRI 305-1) and significant air emissions (GRI 305-7) are requirements that are suitable for improving the sustainability of a company, according to the GRI standard. Since vehicles are responsible for a large part of the global impact with regard to energy consumption and also air emissions, there is a lot of potential leverage in this area.

Status quo of the internal combustion engine

There is no question that electric mobility is the future. However, we should not forget that with its long-term development with regard to specific fuel consumption and exhaust emissions, the internal combustion engine has become much more sustainable. With after-treatment of exhaust gases and optimised combustion, this technology could be considerably improved, even if this success has been tarnished somewhat by “cheating scandals” and the increase in the larger number and weight of cars.

Downsizing and LSPI

Over the past years, this technological progress has been driven by downsizing. Better consumption and emission values have been achieved by reducing engine displacement and, at the same time, increasing power output. Low-speed pre-ignition (LSPI) is regarded as a limiting factor for further optimisation.

LSPI is characterised by a particularly rapid increase in pressure in the combustion chamber before this is actually supposed to take place. Since the ignition is still in the compression stroke, this causes the especially high pressure. The permitted maximum pressure of the engine is often exceeded. The resulting high mechanical stress on the engine block, cylinder head and pistons leads to sudden failure of these components. Even a few occurrences of LSPI can seriously damage an internal combustion engine.

The impacting factors for LSPI include design elements, contamination in the combustion chamber and the composition and properties of the engine oil and fuel. While the composition of the fuel has a direct influence on LSPI tendency, deposits can trigger events such as this.

Influence of TUNAP additives on combustion chamber deposits and LSPI

microflex® 978 Combustion Chamber Cleaner can remove deposits and, as a result, significantly reduce the LSPI caused by this. This has been proved impressively in engine tests carried out at the renowned Institute for Powertrains and Automotive Technology at Vienna University in Austria.

Other engine tests have shown that the tendency for these events to occur can be significantly reduced even in a clean combustion chamber. Our patented formulation considerably improves the properties of the fuel and, consequently, increases the areas of application and safety of this technology that especially saves energy and emissions.


Quantitative estimates of the use of the additive on global energy consumption, CO2 and NOx emissions for petrol engines

With downsized engines, it is assumed that about 10-15% energy and CO2 are saved and that NOx emissions are reduced by roughly 20-25%. Currently, our additive is used by car makers to introduce this energy-saving technology also to the markets in countries with unreliable fuel qualities.

By adding 150ml additive to 150 litres of fuel (every third tank filling), for the above-mentioned savings potentials of engine downsizing, this would mean a saving of 25 litres of fuel, the equivalent of 60 kg CO2.

If for a petrol engine, you assume about 20 mg NOx emissions per km, the effect of downsizing over three tank fillings is about (150l)*(10km/l)*(20mg/km)=30,000 mg or 30g NOx.

Certainly, the simplification that every use of the product is equal to the effect of downsizing is not completely correct. In practice, the product is also used in a precautionary manner in vehicles that are already on the market and, therefore, do no generate any additional use of this energy-saving technology. However, if you consider the longer durability of the engine as a result of reducing LSPI, this does produce an additional sustainability effect.


GRI: 302-4:
Reduction of energy consumption

GRI: 305-7:
Nitrogen oxides (NOx), sulfur oxides (SOx), and other significant air emissions

Area: 300 Environmental

More information:
Wikipedia: LSPI


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