Hybrid drive for Dennis Eagle

Refuse specialist Dennis Eagle, which falls under the Penske Commercial Vehicles group of companies, has revealed a clever new hydraulic hybrid drive system at the Brisbane Truck Show.

Called 'Runwise' and produced by US firm Parker Hannifin, at the show the system was fitted to a Dennis Eagle Elite 2 6x4 chassis awaiting a refuse body for testing.

In short, the system replaces the truck's conventional transmission with a hydraulic unit that manages the power to the drive axles. On first start-up, a pump pressurises the accumulators. On take-off, the transmission takes pressure from the tanks and runs it through two hydraulic motors to accelerate the truck to between 50-60km/h. When the accumulators are exhausted, the Cummins ISL takes over to provide cruising power.

Each brake application reverses the hydraulic flow through the twin pumps and builds pressure. The recharging process means the hydraulic pumps act like retarders and provide all the braking effort, leaving the service brakes unused most of the time.

A full stop will fully charge the accumulators in a matter of seconds. Over 70km/h, the engine drives the truck through a driveshaft that connects directly with the drive axles.

Dead simple really, and as the energy storage process is hydraulic/mechanical, there are none of the downside shortcomings of battery packs and electric motors.

According to Mark Gobessi (pictured), General Manager for Dennis Eagle, the system ushers in a new era for the waste industry.

"This is the world's most advanced, hydraulic hybrid drive system," he said.

"It changes everything. Fuel economy – 40 to 60 per cent better. What does that really mean? In a typical side-loader operation that means an extra $30,000 a year per truck in fuel savings.

"Emissions – 40 to 60 per cent better. What does that really mean? Forty to 50 tonnes of CO2 eliminated per truck per year.

"Brake wear – up to 15 times better. For a conventional side-loader that's probably a $30,000 saving over the life of the truck. And up to 15 per cent better performance or productivity – it's quieter and faster between the bins when collecting garbage."

The system will be undergoing trials with key customers over the next 18 months and will be commercially available at the end of 2016.