Caterpillar Continues to Test New System By the MorElectric System Design Team Fuel prices and anti-idle legislation are the two topics sure to stir debate and rancor in the heavy-duty/off-road vehicle world. Diesel fuel prices, often higher than pump gasoline, continue to climb and the movement to reduce diesel idling affects both over-the-road and off-road segments, as communi- ties enact environmental legislation against it. Commercial vehicles may idle for significant hours to provide a comfort- able cab temperature or to enhance cold weather starting. The EPA estimates that 11 percent of a typical Class 8 truck’s total annual fuel is consumed at idle. Overall, it’s estimated that heavy-duty vehicles at idle consume approximately one percent of U.S. diesel fuel. Even part of the National Energy Policy is specifi- cally focused on reducing fuel consump- tion and emissions from idling trucks. A heavy-duty truck can consume up to one gallon per hour while idling, and with a per-truck average of 1,800 hours per year of idling time, the trucking industry spends over $1 billion annually to provide operators a comfortable cab environment. Additionally, the emis- sions produced during idle are equiva- lent to that from 15 million cars. The challenge is to find a cost effec- tive alternative to idling trucks during extended rest periods and to reduce fuel consumption in over-the-road use. Caterpillar, a major manufacturer of engines and over 300 heavy and special- application vehicles, is working on the problem. Some of the engine acces- sories in use were originally derived from the automotive industry where the focus has been a lifetime of approxi- mately 150,000 miles. That’s not good enough for today’s heavy-duty trucks with their expected useful life of 1,000,000 miles. Cat’s new MorElectric system will drive various engine accessories electri- cally to improve fuel economy, and increase reliability, durability and serv- iceability. System components and engine accessories are specifically designed with the life and robustness needed for heavy-duty mobile equip- ment. Powering these accessories at only the actual speed, flow or pressure required enhances fuel economy and vehicle performance. Modular plug-in subsystems allow for cost effective common parts usage and enhanced serviceability. This tech- nology is not limited to on-highway vehicles, but is also applicable for con- struction equipment, emergency and military vehicles, and RVs. The technology also allows better flexibility in locating components and can reduce the heat load on the radiator system. Various pumps, compressors, and other accessories all compete for space, and through their belts and pulley rob the engine of fuel and performance. The new technology drives these acces- sories electrically increasing the power available to the driveline and offering solutions to reduce idling. The system is currently undergoing field validation testing, and units are being operated on both highway trucks and a variety of off-road applications. The hardware under test uses production- intent tooling and processes. The MorElectric system is a product of Caterpillar’s Electronic & Electrical Systems business unit and will be sold to OEMs for installation at their assem- bly facilities. The system is designed to be compatible with any engine an OEM elects to use. Power Generation Alternators have historically been one of the top reliability problems for heavy-duty mobile equipment. The MorElectric generator incorporates switched-reluctance technology and is specifically designed for heavy-duty mobile applications. It is expected to provide more than double the reliability and durability of current automotive style units. The new generator is engine-mounted and belt-driven like today’s alternator. It has roughly the same package size as the typical 12-volt alternator, but provides 7,300 watts on a 340 volt DC bus. A voltage converter provides the 12 or 24 VDC needed for the vehicle’s conventional systems. If the concept and power numbers look familiar, they are. Cat is using tech- nology found in today’s hybrid vehicles to achieve high power densities and fuel savings for the same technical reasons. The company’s engineers found that the power needed to run accessories on heavy-duty mobile equipment is the same as that needed to launch an auto- mobile from a stop sign. The system’s generator may be used to power additional electrical devices such as boom equipment, tailgate lifts, or (with the use of 110/240 VAC invert- ers) could also power appliances, hand tools, or emergency lights. Additional electrical devices will operate off this electrical system bus in the future, and are being developed by various industry providers. Look for electrical water and oil pumps, and electric power steering systems in the not too distant future. One key to extended longevity of the new generator is elimination of sand and debris that enter through the air cooling fan on