Best of both worlds

Waste and recycling facility managers have been willing to use electric-powered material handling equipment in some applications, though the market for the machines is evolving slowly in North America.

Differences in cost between gasoline, diesel fuel and electrical power remain a foremost consideration. Attention to indoor air quality and decarbonization pledges, meanwhile, could increase the use of electric motors.

The deployment of an electric-powered material handler in Germany provides a recent example of how one waste management firm has found an electric handler to meet its heavy-duty performance requirements.

Fuel for thought

Olpe, Germany-based Hufnagel Service operates what its equipment supplier Sennebogen Maschinenfabrik GmbH calls one of Germany’s most modern waste and recyclables sorting facilities.

Motivated in part by energy cost savings, family-run Hufnagel Service worked with Sennebogen and its service partner Baumaschinen-Rhein-Ruhr to find the right material handler model. Ultimately, the company selected an electric-powered model with a slight diesel-fueled twist.

The Sennebogen 821 E material handler has turned the company’s “energy-saving vision into reality,” Sennebogen says. Hufnagel Service added the 821 E in 2020. Since then, the electric material handler with an 11-meter (36-foot) sorting arm has been put to the task of handling around 125,000 metric tons of inbound material per year.

Sennebogen says the choice of the 821 E did not focus so much on the use of batteries and its operating range. Instead, the decision revolved around “practical cable-based solutions that make sense economically [and] guarantee maximum flexibility and eco-friendly operation.”

A 90-kilowatt (kW) electric motor powers the model, which is configured on a wheeled platform to allow it to move to and from the steady stream of material that arrives at the sorting plant daily.

Hufnagel Service opted for a material handler that is connected to the power supply via a permanently installed cable on the ceiling of the plant. A notable innovation is the diesel generator that replaces the rear ballast. With this Sennebogen diesel powerpack, the machine conveniently can be moved out of the indoor portion of the facility for outdoor maintenance work, remaining “more agile than a stationary electric solution,” Sennebogen says.

Forward thinking

The Hufnagel Service facility sorts and processes recyclables on nearly 30 acres of land. The 821 E is far from the firm’s first encounter with Sennebogen equipment, with the company having used several of the manufacturer’s material handlers in the 817, 821 and 825 model range previously.

Together with his brother, Oliver Hufnagel, Marc Hufnagel runs the family business, which was founded in the 1990s and now has about 200 employees. Sennebogen says, “The company can confidently be considered one of the thought leaders in the recycling industry, regularly investing in future-oriented technologies.”

Because of commercial scrap and waste regulations that became law in Germany and the EU in 2018, the requirements for separating material to be processed increased considerably. Since then, at least 30 percent of recyclables must be extracted from the commercial discards stream, which otherwise is converted into a fuel for waste-to-energy plants, Sennebogen says.

In 2016, the Hufnagel brothers made the decision to build what they consider to be one of the most modern sorting facilities in Germany on the 30-acre premises. The 821 E electric mobile material handler has been part of the business since 2020.

“Initially, we had used a Sennebogen with a diesel engine in the 5,000-square-meter (54,000-square-foot) hall in front of the shredder and noticed that we didn’t actually move it from the spot, except for maintenance work,” Marc says. “Now we feed the plant with an electric material handler [that includes the] additional diesel generator at the rear.

He adds, “This auxiliary engine allows the machine to remain just as maneuverable as the previous model. However, we are now saving on operating costs in a big way by relying on the electric drive.”

Marc cites several other reasons in favor of switching to the electrically powered material handler beyond the perceived environmentally friendly aspects:

• It produces no exhaust fumes, making it a welcome alternative for indoor use.
• The 821 E can call up its full power immediately after the engine is started.
• The machine promises a much longer service life.

The electric model also requires less frequent maintenance. As one example, oil or fuel filters do not have to be changed. As well, the 90-kW electric motor, classified according to Ingress Protection (IP) Code 65 enclosure protection, was installed for a reason, Marc says.

“You can’t imagine what a big problem the fire hazard caused by lithium-ion batteries has become in our industry,” he says. “Batteries and rechargeable batteries are now installed almost everywhere, from children’s toys to electric bicycles and power tools. When these have not been properly removed before disposal and are subsequently damaged in the shredder, the heat generated usually leads immediately to minor or major fires that are difficult to extinguish.”

If such a fire were to occur in the Hufnagel Service facility, an automated fire extinguishing system that monitors the entire facility using thermal imaging cameras would initiate the dispersal of firefighting foam, even if the electric material handler remains within the hall.

“It may happen that our 821 E gets exposed to the foam before it can be driven out of the hall with the help of the Powerpack,” Marc says. “The IP65 electric motor is ideally suited for the conditions in our hall. Additionally, we have to use a dust-binding system, which leads to an increased humidity in the air.”

The protective measures Sennebogen offers provide an umbrella. “All these environmental conditions are difficult to cope with [when using] unprotected electric models,” Marc adds.

This article includes information supplied by Sennebogen Maschinenfabrik GmbH.