A One-Month ROI


The statement below is from a maintenance man who works for his state’s Department of Transportation about the results of an Autotherm System that he installed in a Class 8 Volvo used as a snow plow in the mountains of that state in January of 2007.

"This is a follow-up to the installation of the Autotherm system onto… a Volvo 10 yard truck on January 11th and 12th.

After getting the truck back to the junction on the 12th, I installed an hour meter under the dash that tracks the time the key is off and the Autotherm is functioning.

I had initially estimated that the idle time per day would be at least 4 hours, figuring 2 shifts a day that include two lunch breaks, four mid-shift breaks, plus time spent washing the truck at the end of each shift.

After six days the meter showed that the system had been used for 32.5 hours.

On February 5th the meter reading was at 130.5hours. That equates to 24 days since installation, with an average daily use of 5.43 hours.

The charts shown us at the class prior to the installation listed that these Volvo engines use approximately 1.5 gallons of fuel per hour idling. This comes to at least 8 gallons of fuel savings per day. I’m not aware of the cost per gallon of fuel that the state pays, but, figuring $2.50 per gallon that comes to around $20.00 each day in savings for fuel only.

The initial cost after installation for each unit should be about $710. This is on a single unit cost of about $530 and about 3 hours for our installation at $60 per hour for a total labor of $180.

This means that at the current use of the system the savings in fuel alone will pay for the unit and the installation in approximately 36 days on double shifts or 72 days on single shift.

There are other pluses to this system being installed. Such as less fuel dilution into the crankcase and more even cooling of the engine cylinders after shut down resulting in less hot spots on the liners, which should result in better engine life.