How much time each day does your fleet spend idling? Do you know what idle time is costing your business? The reality is idle time is probably costing your business more than you think, and your vehicles are also probably idling for longer than you think.

Idle time happens in a range of situations:

• When vehicles are in traffic
• While loading and unloading
• While the driver processes paperwork
• While the driver talks on the phone
• During driver downtime, such as when they eat and, sometimes, sleep
• Warming up or cooling down the interior of a vehicle in winter or summer

Average fleet idle time

The percentage of idle time over a working day varies depending on the type of vehicle. For example, a delivery truck is likely to idle longer each day than a semi-trailer. The average idle time, however, is 25 percent idle time of the vehicle's operational time per day.

The idle times for plant machinery and heavy equipment is even longer. Maintenance graders and loaders can be idling up to 40 percent of the time, while construction machines can spend up to 30 percent of their time idling.

Why reducing idle time is important

When you reduce idle time in your fleet you will:

• Reduce fuel use so will lower fuel costs and reduce harmful emissions
• Reduce engine wear increasing the capital value of some machines as well as making vehicles and machines more reliable
• Reduce noise pollution
• Improve air quality in work areas

Cost of fleet idle time

These are the average fleet vehicle idle times and fuel usage per hour:

• Standard passenger vehicle - 0.5 to more than 2 litres
• 2-8 tonne rigid truck - 2 litres
• 8-16 tonne rigid truck - 3 litres
• 16+ tonne rigid truck - 4 litres
• Semi-trailer - 4 litres
• Bus - more than 3 litres

To put a financial cost to this idle time, a normal truck idling for 25% of is working day will use $2,500 worth of fuel per year during this idle time. That's a cost that could easily be saved.

And plant and heavy equipment? A wheel loader will on average use $12,000 worth of fuel per year just to keep it running during idle time.

All the figures above are significant, particularly when you consider they are avoidable. In other words, the money you currently spend on fuel for fleet idle time could be going towards your organisation's bottom line rather than to your fuel provider.

The maintenance factor

Engine idle time can also have a negative impact on engine performance as it increases wear. This can increase maintenance costs for your fleet.

We assume one hour of idle time is equivalent to driving about 40km. If you have a vehicle that needs an oil change every 8,000 km and you drive it 80 miles a day, you will change the oil every 100 days.

If the vehicle is idle for one hour a day, however, the engine goes through additional wear equivalent to an extra 40km per day. That means after 100 days the engine will have wear equivalent to 12,000km - that's 50 percent more than recommended for each oil change.

This could lead to reliability issues which can result in downtime, lost productivity, and costly repairs.

Other impacts of idle time

• Machine resale value - Idle time can accelerate the depreciation of your machinery. A Caterpillar 12H grader, for example, could be worth $30,000 less if it has 10,000 hours on the hour metre compared to the same machine that cut its idle time by 25 percent and so only has 7,500 hours.
• Environment- While your vehicle uses fuel, it is causing emissions which are harmful to the environment. Some people think idling is better for the environment than constantly switching the engine off and on again. However, you use more fuel (and create more emissions) idling for 10 seconds than you do switching your engine off then restarting it.

How to reduce fleet idle time

There are two main steps you should take to reduce fleet idle time in your business:

• Educate and motivate your drivers - Encourage your drivers and machinery operators to switch off their engines when they are not in use or not in motion.
• Monitor - Get a better understanding of idle times in your fleet using Smartrak's Fleet Management software. It knows when the engine is switched on and the vehicle is stationary so gives accurate readings of idle time. This lets you focus on specific drivers or sections of your fleet that have the worst idle times so you can help them improve their performance.

The savings to your business by reducing fleet idle time are too significant to ignore.