Gen-Sets Designed To Take The Idle Time From Trucks

Diesel Progress North American Edition, May, 2001 by Brent Haight

It has been estimated that an idling truck burns up to $20 worth of fuel per day. At that rate, the cost of idling adds up to roughly $5000 to $6000 per year. With the rising costs of fuel, many truckers are looking for alternatives to idling.

While the concept of small standalone generator sets for commercial truck applications isn't new, TruckGen has taken designs originally developed for harsh, salt-water marine generator applications and developed a line of compact, lightweight diesel generators that consume between 1/10th to 2/10th gph, the company said.

The UCT1-3.5 and UCT2-5.5 generators offer 3.5 and 5.5 kW outputs respectively and are designed to run electrically driven air conditioners and heaters, as well as all of the onboard 120 V appliances and equipment found in today's commercial trucks.

Each generator model uses a liquid-cooled Kubota diesel engine to drive a two-pole Stamford Newage brushless generator through a Goodyear 1 1/4 in. helical-cut toothed belt. According to TruckGen, this drive system enables the engine to run at 2800 rpm while the generator spins at 3600 rpm, providing quieter performance and less vibration.

Due to its compact size, the UCT1-3.5 provides 12 V, 40 amp battery charging through an electric battery charger, while the UCT2-5.5 has a 40 amp alternator as standard equipment.

"Basically we took the technology that was already proven from the marine side and went to work engineering a generator set for trucks," said Klaus Holze, sales director for the Jacksonville, Fla.-based manufacturer. "We looked for the right box enclosures, the right radiator combinations, the right muffler combinations. The result is a smaller, lighter diesel generator set for the transportation market."

The generators are cooled through Universal UAR radiators mounted on the backside of the generator's aluminum enclosure. "The generator is not tied into the truck's cooling system at all," said Holze. "The danger of tying into the truck's system is that if there is a fluid leak, you could potentially ruin the main engine, or at least put it to a standstill, This way, the gen-set has its own dedicated cooling system and there is no interference with the truck."

Exhaust is vented through the back or bottom of the enclosure through a metal flex hose. A critical grade muffler is attached to the exhaust for sound attenuation. "We run the muffler wherever the truck allows us," said Holze. "We've run them under the box, beside the box, behind the box. Each application is different. It all depends on available space."

Other components include Facet fuel pumps, which draw diesel from the main vehicle fuel tanks; Donaldson air cleaners; Synchro-Start run solenoids; and Nason shutdown switches.

The 7 hp, 3.5 kW UCT1-3.5 generator, which is powered by a single-cylinder, Kubota EA300 horizontal diesel engine, measures 28 in. long x 16 in. deep x 17 in. high and weighs 160 lb. without the aluminum enclosure.

The UCT2-5.5 gen-set, which incorporates a two-cylinder Kubota Z482 diesel engine rated 11 hp, measures 23 in. long x 20 in. wide x 17 in. high and weighs 240 lb. without the enclosure.

"We created a system that is easy to work on," said Holze. "You don't have to crawl underneath the vehicle to do oil changes or other routine maintenance because all of the service points are on one side."

The generator sets are connected to the vehicle by the battery cables, fuel lines and electrical output. Remote start panels are installed inside the cab of the truck with 20 ft. wiring harnesses. According to TruckGen, installation can be accomplished by a competent mechanic in six to eight hours.

The UCT1-3.5 gen-set was designed to fit inside existing truck battery boxes and a custom-built aluminum box is available for both gen-sets to fit almost any truck model. According to TruckGen, the enclosure can be easily mounted on a truck's frame rails or behind the cab.