By Bryan Couch
Executive Director
Product Development and Planning
Motor Coach Industries
With the average motorcoach racking up 100,000 miles annually and diesel fuel averaging more than $1.74 cents a gallon ($2.35 on the West Coast), operators are paying close attention to fuel efficiency more than ever.
Just how much more in fuel costs are operators paying these days?
Assuming the average coach burns nearly 15,000 gallons of diesel a year, that coach would consume more than $26,000 worth of fuel at current prices. That same fuel cost just over $21,000 last year. That's $5,000 lost to the bottom line for each coach.
Fundamentally, there are three factors that impact fuel economy: (1) Vehicle characteristics, including drag, rolling resistance and ancillary engine loads; (2) vehicle specifications, including powertrain options, and (3) driver performance.
While equipment, engine and transmission manufacturers continue to explore ways to get more miles per gallon, there also are steps operators can take to save fuel. Let's explore those options.
Drag starts to become the predominant factor affecting fuel consumption at speeds above 55 mph. To reduce drag, lower the cruise control and vehicle speed limit parameter settings. By reducing the engine's programmed vehicle speed limit parameter from 72 miles per hour to 66 miles per hour, one of our customers found a 10 percent increase in average fuel economy.
A 10 percent fuel economy gain at today's prices translates to more than $2,500 in reduced annual fuel costs for the average coach.
To ensure rolling resistance is as low as possible, make sure wheels are properly aligned and tires are properly inflated. Follow the manufacturer's guidelines for wheel-bearing torque, and ensure brakes are properly maintained. Proper maintenance can make a big difference when it comes to getting better mileage.
Don't overload the engine. Keep the HVAC, electrical and engine cooling systems operating at peak efficiency by following maintenance guidelines. Reduce the amount of time the HVAC compressor is in lockup and the number of compressor cylinders that are loaded. Once the cabin reaches the peak comfort level, reduce the HVAC fan speed.
Electrical loads can be reduced by selecting a lower interior light setting and replacing incandescent bulbs with energy efficient LED lamps.
When it comes to vehicle specifications, remember to consider fuel efficiency in powertrain options during a new coach purchase. MCI, for example, offers both the Detroit Diesel Series S60 engine with cooled EGR technology and the CAT C-13 ACERT engine, which can be combined with either an Allison B500 or a ZF ASTronic transmission. Certain combinations of these are said to decrease fuel consumption.
Consideration also should be given to axle-ratio options based on applications and performance demands of the coach.
Despite the advances made to engines and transmissions by manufacturers and the fuel-saving procedures adopted by operators, it's often the right feet of drivers who have the most control over improving a fleet's fuel economy.
Here are three good tips for improving driver fuel economy:
* Recommend that your drivers let the coach coast when coming to a stop rather than having the retarder or Jake Brake in the latch mode. That will produce better fuel economy in heavy traffic.
* Ask drivers to avoid extended periods of idling while taking breaks or waiting for tour groups.
* Have drivers shop for fuel carefully. Savvy drivers know which states, counties and facilities offer the best prices and plan their fill-ups accordingly.
To get the latest data on diesel fuel prices across the country, visit the U.S. Department of Energy Web site at www.eia.doe.gov.