In today's world, energy efficiency is vital to truck manufacturers for both ecological and economical reasons, which is why all effort and technological developments are channelled in this direction, with the help of electronics.
Reduced consumption and low emissions are possible through the optimisation of the electronic management of powertrains, emergence of next generation technologies and the development of building materials capable of delivering high performance.
But to get here, the industrial vehicle has had to come a long way. Thirty years ago a large-tonnage truck easily consumed 50 L/100 km, while this same truck currently consumes 40-45% less fuel, emits 90% less emissions and provides twice the power. Who could ask for more?
Since the introduction of the Euro 1 standard (1993), industrial vehicle manufacturers have ploughed a lot of resources into preparing their engines for a successive reduction in emissions.
Compliance with Euro 1, and subsequently, Euro 2 (1996), simply required adjusting the combustion systems and final developments of the powertrain, “camouflaging” the increase in consumption.
The real revolution came with Euro 3 (1999), when manufacturers had to completely rethink the design of their engines, particularly large displacement ones, which led to the disappearance of many existing mechanisms.
The arrival of Euro 3 led to the general introduction of electronic control (EDC) systems which have been around since the late eighties through Bosch. Aside from EDC there are new supply and combustion systems, such as multi-valve technology (four per cylinder), a solution that Pegasus had already developed in 1958 for 165 hp, waste gate valves and variable-geometry turbo.
The subject of injection has also seen the start of the development and implementation of the most common fuel treatment systems, technologies now bordering on perfection, split essentially into the following three mechanisms: unit injectors, unit pumps and common-rail.
The application of Euro 4 regulations (2006), especially with the arrival of Euro 5 (2009), saw manufacturers opting for both EGR-SCR in reducing emissions. At the same time, injection systems continued to evolve at an unstoppable pace. The initial trend was a moderate increase in consumption, which for a 40 ton trailer powered by a driving force of between 420 and 460 hp could mean between 35 and 38 litres/100 km.
There are currently two circumstances that favour the increased energy efficiency of diesel engines. The first is the rise of trucks with between 460 and 480 hp, a segment which was previously served by 13 to 16 litre cylinder blocks, but which now, thanks to technology and new materials, only needs “compact mechanics” of 12-13 litres. The second of these circumstances is the extraordinary development of injection systems, capable of achieving a perfect job of atomisation and swirling in combustion chambers.
As engines become “greener”, they tend to consume more. To reduce emission levels, particularly nitrogen oxide (NOx), the temperature of combustion chambers need to be lowered, an action which conflicts with a diesel engine’s thermal principles.
The more heat we generate, the greater the energy developed and work we can produce, so cooling combustion chambers is a contradiction which manufacturers have successfully overcome, achieving the miracle of greener engines and lower consumption.
And this miracle has come about through the use of electronics in managing all a vehicle’s parameters.