Diesel-powered trucks, buses, and off-highway equipment have large, complex drivetrains that suffer from similarly oversized energy losses as they operate. These heavy-duty vehicles (HDVs) currently produce 8% of the U.K.’s overall CO2 emissions, but their fuel efficiency (and thus their carbon footprint) could improve by 2% to 5% if energy losses stemming from their gears, bearings, and lubrication systems could be halved, said Chris Thorne, Program Manager for HDVs at the U.K. Energy Technologies Institute (ETI).
ETI is a public-private partnership between global energy and engineering companies and the U.K. government that is aimed at accelerating development and deployment of affordable low-carbon technology solutions in the U.K., according to Thorne. The consortium helps “bridge the gap between government- and industry-supported R&D work and the market.”
The collaboration includes BP, Caterpillar, EDF, E.ON, Rolls-Royce, and Shell, as well as the U.K. Government’s Engineering and Physical Sciences Research Council and Technology Strategy Board, and Departments for Business Innovation & Skills, and Energy & Climate Change.
Cutting parasitic losses
The goal of a three-year, £2.5-million ($3.9-million) project launched recently by the ETI is to boost the fuel efficiency of large trucks and off-highway machines by cutting in half the amount of parasitic losses that occur in their lower drivetrain system. Such an advance, Thorne said, “has the potential to make a beneficial step change to the HDV industry.” The HDV category includes tractor-trailer trucks, coaches, construction and mining machines, tractors, back-hoe loaders, wheeled loaders, agricultural equipment, and articulated quarry trucks.
An earlier ETI feasibility study on the topic that was conducted by Ricardo, Caterpillar, and Rolls-Royce in June 2010 found that investment in, and the testing of, a range of basic platform technologies is the surest way to accelerate green vehicle technology.
The ETI commissioned Nottingham-based driveline consultants Romax Technology to lead the joint effort, which will also include Castrol of Pangbourne, U.K., and Ansys of Canonsburg, PA.
Romax will use its decades of know-how in gearboxes and software simulation to address the lower drivetrain design and analysis tasks, whereas lubrication/tribology specialists from Castrol will handle the oil development issues and CAE analysts at Ansys will model the HDV lubrication system with its latest engineering simulation technology.
“We have over 20 years experience of drivetrain design,” said Peter Poon, Chief Executive and founder of Romax. “The ETI has set an ambitious target for parasitic loss reduction in this project but we are confident it is achievable as it matches our thinking in this area. It will make a big difference to future HDV drivetrain design technology. We are [all] keen to begin development.”
“We want to get each of these parties—specialists in engineering, modeling, and lubrication—around the same table to co-engineer a general solution in an environment where the normal business-related constraints have been removed,” Thorne said, adding that the hope is that a different R&D framework will engender novel improvements.
The team will study parasitic losses deriving from waste energy expended in the agitation of the lubricating oil and surface-to-surface component friction, which together can account for more than a tenth of overall vehicle energy losses. This project will look to improve the overall system design, with a synergistic focus on improving the mechanical and operational efficiency of gears, bearings, surface treatments, lubricant flow, and lubricant composition, according to ETI.
Articulated truck demo
The driveline technology will be demonstrated on a Caterpillar AT725 articulated truck, which is considered representative of other models in the HDV category. Installation of the new technology will take place at Caterpillar’s Peterlee, U.K., factory.
“ETI’s HDV program, executed by Caterpillar, will help us identify the next generation of breakthroughs in vehicle efficiency and carbon dioxide emissions reduction for these trucks and other Caterpillar products,” said Caterpillar Vice President and CTO Tana Utley at an introductory ceremony at the Peterlee plant in March.
This project is the first of a £40 million ($65 million) ETI program designed to boost HDV efficiency by one-third. The joint research effort will focus on the concept engineering of a range of innovative and efficient land vehicles.
Incorporating individual technology developments into packages that can be implemented across a range of vehicles will be critical. During phase 2 of the program, the ETI will invest in the under-developed technology areas prior to a full-scale demonstration of all of the technologies and systems in phase 3.
The expectation is that vehicles incorporating technologies from this program will reach the market by 2020.