For the past five years, Scania’s super-dedicated R&D teams have turned over every stone to develop the most energy-efficient and sustainable combustion engine platform the heavy transport industry has ever seen. Here’s how they came up with the super-efficient Scania Super.
How do you improve an engine platform that has won the European Green truck award five years in a row? How do you develop a powertrain that will strengthen Scania’s industry-leading position within sustainable transport for the rest of this decade? How do you secure wins in future fuel consumption tests, an area in which Scania has a proud record that it doesn’t want to lose?
The developers at Scania Technical Centre who were given these assignments say the answers are: determination, innovation and customer focus.
Completely new platform
“We had the privilege to start with a blank slate and develop a completely new 13-litre engine platform,” says Assistant chief engineer Linda Pukk Berggren.
“Starting from scratch meant we could concentrate all our design work with the customers’ needs in focus, without restraints. That’s why we can now present a product that the transport industry really needs here and now to take the necessary steps towards a sustainable future,” she adds.
With the Super engine platform, Scania’s engineers struck the perfect (and delicate) balance between a high-performing engine and an aftertreatment system that is as efficient as possible in limiting emissions but at the same time is “non-intrusive” for the engine and lets it fulfil its potential.
“We reach up to 50% in brake thermal efficiency. This is quite remarkable and means that a whole new level of energy is going directly to the wheels. What is also important is that fuel consumption is significantly reduced for a very broad part of the engine speed and load area. This means that many different applications, such as long-haul, construction and forestry vehicles, will all benefit from the improvements and emit less CO2,” says Magnus Nilsson, technical mnager within Aftertreatment.
Thanks to this outstanding energy efficiency and other major updates in Scania’s powertrain – such as a new gearbox and a new range of driven rear axles – fuel savings of eight% or more can be reached for long-haulage operations. And that’s in comparison with Scania’s already industry-leading performance levels. Efficient just became super-efficient.
So, what’s ‘under the hood’ of the new 13-litre engine? Quite a lot, in fact.
New features include dual over-head camshafts, optimised injectors, improved combustion, an optimised high-pressure fuel pump, improved cooling and lubrication, increased turbocharger efficiency, and a state-of-the-art engine management system.
Not only that; Scania’s successful dual dosing Selective Catalytic Reduction system, which has been proven to offer excellent fuel saving capacity and increased productivity and uptime, has been remade from the ground up. The system has earned a name of its own: Scania Twin SCR.
“Our new Twin SCR aftertreatment system is an inventive ‘chemical factory’ designed to utilise the limited heat that exits the efficient engine. It is capable of dramatically reducing emissions of nitrogen oxides and particulates. The concept is also future-proof for stricter environmental legislation in the years ahead,” says Nilsson.
Dual over-head
Both Nilsson and Pukk Berggren say they have vivid memories of the five-year long development process. And, at more than two billion euros, it is one of Scania’s largest-ever investments in a new powertrain.
In 2019, Nilsson says the developer teams were quite puzzled when testing trucks with the new engine platform in the heat and high altitude of the Sierra Nevada mountains in southern Spain. The data indicated a significant reduction in fuel consumption of approximately 10% in some tests – compared to the current award-winning Scania product that will be replaced by the new platform.
“We were fault-checking the test equipment because we questioned the readings, especially as the exhaust flow was comparatively low. Exhaust flow is an important parameter for designing the aftertreatment system and for the catalyst sizing. The higher the exhaust flow rate, the shorter time the catalyst can use to reduce the emissions. The experiments were re-run and confirmed in test cells at R&D in Södertälje. And we realised: the new engine was that good; we actually achieved this significant reduction of mass flow and, more importantly, fuel during the tests,” says Nilsson.
For her part, Pukk has fond memories of driving the test trucks down to southern Spain.
“The feel of the trucks and the new powertrain was absolutely amazing. I couldn’t believe how quiet and smooth it was to drive the truck. It’s a personal memory that will stay with me forever,” she says.
Making coaching more efficient
With up to 5% less fuel consumption, coach operators should expect the most energy-efficient Scania coaches yet, which will also meet or even surpass emission targets. It’s crucial for coach operators to minimise the fuel consumption of their vehicles. Fuel is one of the main contributors to the total cost of operation, and margins are tight.
A further challenge is adapting to tough new environmental laws restricting Nitrogen Oxide and CO2 emissions. And coach customers increasingly expect sustainable travel, too.
Scania understands these ‘pain points’, and has put fuel efficiency and lower emissions at the heart of the new Scania bus and coach generation. Three years of intensive R&D have produced fuel consumption savings of up to 5%, depending on emission class (Euro 6, Euro 5, etc).
“At the outset of this project we set a target of reducing fuel consumption for our travel coaches by an average of four to five% from our previous model. I’m happy to say that we have achieved that, thanks mainly to the new powertrain,” says Niklas Berglund, expert engineer at Energy Consumption, Bus Chassis Development.
That the coaches are using the same types of driveline components from Scania trucks has also been beneficial.
“While the coach sector still lacks an equivalent energy use standard to city buses’ Standardised On-Road Test (SORT), the fact Scania trucks with these components have won the annual green truck award five years running, plus numerous other industry tests, means most comparisons in energy efficiency will be the same,” says Berglund.
The new engines also meet or even surpass the more stringent Eu6E emissions guidelines; reassuring for operators facing ever tighter regulations.
And, all Scania coaches and buses can be run on biofuel, a cleaner option and an important stepping stone on the way to fossil-free transport.
After three years of groundbreaking development, Scania is giving coach operators the most fuel-efficient, sustainable, comfortable and driveable vehicles yet.
“This is an important step forward for Scania. We have to lessen the amount of traffic that’s on the road, and buses have an incredibly important role to play in boosting public transport and sustainability,” says Berglund.
“My main hope from this new bus generation is that it will really open customers’ eyes to our tremendously good powertrain in terms of its energy consumption and emissions levels.
“And that they also understand that we can truly go not just nearer neutral in terms of fossil fuels, but switch to biofuels, where possible.”
Read the full article in the latest issue of Truck and Fleet Middle East magazine!
