Plug It In

Truck Stop Electrification Gaining Momentum

By Tom Kelley

At first glance, the concept of Truck Stop Electrification (TSE) may seem like a nice convenience for truckers and a good way to sell a few more AC appliances for trucks, but there is a much loftier goal involved here. As environmental regulations are tightened, the industry needs to find ways to reduce its total output of air pollutants. According to numerous studies, typical overnight idling practices contribute approximately 40 million tons of exhaust emissions to the environment each year. Letting trucks plug in, instead of idling, would have a significant positive impact on the environment.

Although the environmental aspect on its own may be a tough sell, there's also a significant economic benefit that will likely be the driving force behind TSE. According to a studies by the Edison Electric Institute and the Argonne National Laboratory, idling an engine for 2,500 hours annually is the equivalent of 200,000 extra miles of engine wear, burning 3,750 gallons of diesel fuel, and adding operation costs between $4,000.00 and $7,000.00 per truck per year.

 

An inverter/charger system equipped to take advantage of shore power connections will allow standard 110V AC appliances to be powered from either the truck's electrical system or an electrified trucks top.

Broken down to a per-hour cost, engine idling costs approximately $2.75 per hour. Even at a plug-in rate of $1.00 per hour, the cost to upgrade or equip a truck would generally be recovered in the first year. On the other side of the equation, it's also a quick payback for the truck stop or service provider.

To realize the benefits of TSE, trucks would ideally be equipped with a DC/AC inverter connected to the truck's batteries and charging system to allow use of the AC appliances while en route or for short durations while parked. For longer duration overnight stops, the truck would be plugged into the local electric utility, similar to existing arrangements at RV parks and boat marinas.

When the trucking industry first gave serious consideration to TSE a few years ago, the process was caught in proverbial "chicken or the egg" conundrum. The problem was apparent and the solution was available, but it was unclear as to "what comes first." Should truck stops install the hardware when it will reduce their fuel sales? Should truckers demand the service from truck stops? Should the OEMs add AC shore power systems to trucks before the truck stop infrastructure is in place? Should the utility company step in to develop the market or should third parties take the lead?

In just a few short years, here is what has happened:
Many truck stops now have AC power connections available. Some of these connections have been installed by the truck stop operators and some have been installed by third-party services such as Park-N-View.

 

Inverter/charger systems such as this unit from Xantrex are available as a factory option from virtually every tractor OEM.

IdleAire of Knoxville, TN is currently performing field trials of a truck stop-based system that will not only deliver AC power to the truck cab, but off-board heating and air conditioning as well. According to IdleAire executive vice president Tom Budget, the system should begin commercial deployment in mid summer.

 

George Strickland from Travel Centers of America reports that his company's test site in Willington, CT has seen minimal use, but that this is primarily because the service has not been actively marketed yet. According to Strickland, TSE is still dependent on three factors each gaining critical mass: a larger market for the service, development of the system to handle the actual sale of the power, and finally, equipment and technology that will allow the service to be consistent throughout his (or any other vendor's) locations. "Through our fleet group, we talk with the top 100 trucking organizations routinely and meet with them at least annually. We need them to say that they're electrifying their trucks and need places to plug in," said Strickland.

Not content to rely entirely on the truck stops, many fleets are electrifying the parking areas at their terminals to realize additional savings from idle reduction.

Truck fleets and owner-operators continue to increase the demand for "Shore Power" systems from the tractor OEMs. Volvo reports that roughly 90% of the 770 model tractors sold in the last few years are equipped for shore power. For those not quite ready to take the full plunge, Volvo also offers a pre-wire option that permits the equipment to be added later without retrofitting any wiring. Xantrex, a company that represents the consolidation of several top names in the inverter business, offers a complete shore power kit for factory or aftermarket installation. Virtually every truck OEM now has some form of shore power offering available as an option.

Long known for its RV air conditioning systems, the Domestic Corp.'s has established its Cab Comfort division to develop and market AC powered heating and air conditioning systems for truck sleepers. In addition to being able to run on shore power, the Cab Comfort system can also be powered by Domestic's Kwyatt Power self-contained battery pack and inverter system while en-route or away from the "grid."

Utilities and municipalities are beginning to take an interest in TSE for the potential benefits of helping to meet emission regulations. "Clean air" cities can potentially help offset the cost to electrify truck stops and put AC infrastructure into trucks, thanks to emission reduction credits. Basically, utilities document the reduction in emissions and then can use those emissions to offset, for example, the pollution a new power plant produces. Last year, the credits topped out at $40 for 1 pound of NOx. A truck idles 9/10ths of a pound per hour!!

As the representative of many U.S. utility companies, the Edison Electric Institute (EEI) is planning to lobby in favor of TSE incentives at the federal level. According to the EEI's Rick Tempchin, " to deploy TSE on a large-scale basis, a coalition effort of all participants in the process will be necessary."

And finally, until TSE becomes widely deployed, many alternatives to idling are available. On-board temperature and battery control systems such as those from Temp-A-Start and Webasto are designed to tie in with existing fuel and electrical systems to minimize the need for idling and protect battery voltage for starting requirements.

With the obvious environmental benefits, the local, state, and federal governments should step up to the plate and provide some incentives for developing the necessary infrastructure. Any further emission systems added to trucks are likely to come at great cost and with only a minuscule incremental reduction in emissions. TSE represents an opportunity to drastically reduce emissions industry-wide, on both new trucks and old alike.

Billions of dollars have been spent on nearly-empty HOV lanes around the country, all in the interest of shutting off a few cars for a few hours of commuting, five days a week. Although TSE wouldn't require the same outright "handout" received by the questionably-worthwhile HOV projects, tax credits or incentives for those implementing TSE would most likely get the ball rolling and result in thousands of truck engines being shut off for 8-10 hours per day, seven days a week.

 

The following table summarizes the cumulative reduction in idle time for a 12 week, 12, 24 and 36 month periods based on the elimination of various hours of idle time per night.

Fuel Savings:
The table below demonstrates the fuel cost for one truck that idles for various hours in a day for a 5 day work week over a 3, 12, 24 and 36 month period.

Battery savings
The regular use of the built-in 3-stage temperature compensated battery charger, which activates automatically when a driver connects to shore power, will increase battery life. Based on the assumption that you replace truck batteries at the industry average of every 12 months, the projected cost savings are demonstrated in the table below.
 

Domestic's Cab Comfort heating and air conditioning system can be operated from shore power or an inverter/charger system.

Engine Maintenance
The reduction of engine idling will extend engine service intervals and result in a decrease in engine maintenance costs. The following is a partial list of service items that will be positively affected by a reduction in engine idling:

• Increased intervals between oil changes
• Increased intervals between coolant changes
• Increased intervals between filter changes
• Decreased engine wear

A fuel-pump style card-reader and keypad are used to purchase service through the IdleAire system.

Other "Real" Benefits (not factored into ROI):

• Higher trade-in value
• Lower time on engine
• Inverter/Charger and HVAC system will return a premium
• Driver recruitment and retention tool
• Lower food cost (less meals at restaurants) is like a pay raise for drivers
• Reduction in exhaust emissions may result in government rebates or at a minimum goodwill from the community

 

Fixed Costs:
The cost of the Inverter/Charger system, installed is: $1,600

The cost of the installed AC-powered HVAC system is: $1,200

 

Total system cost = $2,800

Variable Costs National Average for Electricity:

• 0 amps (diversified load) X 120 volts AC = 1200 watts
• 1kW/hour = 7› therefore 1.2kW/hours = 8.4 cents

Based on the above information the cost for electricity is:
 

Hours/Day	Cost/Day	12 weeks	1 Year	2 Years	3 Years
4 hours	34	$20.40	$88	$176	$264
6 hours	50	$30	$130	$260	$390
8 hours	67	$40	$174	$348	$522

Note: Rates for kW/hr vary across the country from approximately 4 to 13› per kW/hr.

Projected Return on Investment (ROI) per Truck:

Hours/Day	1 Year	2 Years	3 Years
4 hours	($1,240)	$320	$1,880
6 hours	($460)	$1,880	$4,220
8 hours	$320	$3,440	$6,560

Note: ROI is based on a $2,800 system purchase and installation and does not include the cost of electricity, nor the savings in battery purchases (which virtually offset each other).

Projected 3 Year Return on Investment (ROI) for Fleets:

Hours/Day	500 Trucks	1,000 Trucks	2,500 Trucks	5,000 Trucks
4 hours	$940,000	$1,880,000	$4,700,000	$9,400,000
6 hours	$2,110,000	$4,220,000	$10,550,000	$21,100,000
8 hours	$3,280,000	$6,560,000	$16,400,000	$32,800,000

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