Editor’s Note: This article has been updated on February 9, 2022 with more details about the electric drive system, including specifications and operating parameters.
Doosan Bobcat has introduced its new, all-electric Bobcat T7X compact track loader at the CES 2022 show in Las Vegas. The T7X is said to be the first machine of its kind to be fully electric and, according to company officials, offers the benefits of eliminating hydraulic systems, emissions and vibrations while providing cleaner, quieter machines.
“This machine is a technological feat for Bobcat and for the entire industry,” said Joel Honeyman, vice president of global innovation at Doosan Bobcat. ”We challenged the status quo to deliver a connected, all-electric machine designed for power and performance that previously was not possible.”
Engineers decided to totally eliminate hydraulics on the new T7X for a couple key reasons, said Justin Odegaard, acceleration manager, Doosan Bobcat North America. “First, a hydraulic system has a lot of connections and components. For every connection point present in a system, there is a chance that the owner will have a potential leak point. Eliminating hydraulics means eliminating the risk of leaks, and therefore, eliminating the potential for downtime.
“Second, going to an all-electric platform is a lot more efficient than a battery pack running a hydraulic system. This gives us longer operating times without the need for a larger battery, thereby increasing productivity and efficiency over the life of the machine.”
The T7X relies on a 460-V electrical system which best optimizes performance and componentry, he said. “This voltage also yielded the efficiency we were looking for in terms of overall design.” At the machine’s core is a construction-grade, 62 kW lithium-ion battery from Green Machine Equipment that powers the loader’s track system and all workgroup functions. The charge can support daily work operations for up to four hours of continuous run time and a normal, full day of operation during intermittent use.
The traditional hydraulic work group has been completely replaced with an electrical drive system consisting of electric ball-screw actuators and electric drive motors. Doosan Bobcat collaborated with Moog Inc., a worldwide developer of motion control components and systems, to speed the pace of R&D for electronic-control capabilities of the T7X.
Early on, ruggedness and life were specific considerations when building out the machine, said Odegaard. “The actuators are extremely durable devices used in harsh industrial applications. When we couple the force and position control of the actuators the system can then ensure design parameters are kept in check to ensure the durability exceeds customer expectations as it compares to a traditional hydraulic system,” he said.
According to Moog officials, most centralized systems on a construction vehicle today have one motor and pump distributing hydraulic fluid; the pump is always running. With a traditional loader, the machine would waste energy on every axis for lifting, tilting, moving — even when the machine is stationary.
Moog designed a more efficient system using distributed control to send power only when and where it is required, such as for lifting dirt or moving side to side, and thus wastes little to no energy. The sophisticated power-management system is programmed to sense when loads are increasing, automatically backing off power when not needed to preserve the total energy use and extend the machine’s run time.
Moog’s system also efficiently manages motion and heat for the T7X, which keeps each component operating at the right temperature range and reduces energy use. And the system’s software learns to optimize movements and operations as the T7X works. Smoothing out the peak moments of energy use can boost run time by more than 25%.
Structurally, only slight design modifications were necessary, due to small size differences between electric and hydraulic components. But for the most part, the T7X looks very similar to conventional machines. “The T7X has the same frame size as our T76 compact track loader, but it’s new from the ground up. It’s built with about half the number of components found in a diesel-powered, hydraulic-driven loader,” said Odegaard.
The T7X is also said to provide high-performance torque and more power than similar diesel-fueled track loaders. “Regarding power and performance, the T7X’s breakout forces were found to be more impressive than that of traditional loaders during testing. Not to mention, the machine offers low-noise operations and, because it does not emit exhaust, makes it a great choice for enclosed jobsites.
“Fluid power is an efficient way to convert energy to motion, since it’s dense and cost effective. An electric actuator is one step beyond this intermediate technology, and Bobcat has developed a software platform that takes advantage of the performance and efficiency of an all-electric system. Pushing that technology to give the customer the very best machine was our objective,” he said.
The new unit uses only one quart of eco-friendly coolant compared to 57 gallons of fluid in its diesel/hydraulic equivalent model. It can also significantly lower daily operating costs, when considering the reduction in annual maintenance costs and elimination of diesel, engine oil, diesel exhaust fluid and hydraulic parts.
“The T7X loader will be in a premium configuration and is priced at approximately three times that of a nicely equipped T76 loader. The T7X loader will cost nearly 90% less to operate than a T76 loader when comparing all input costs for fuel/electricity and routine maintenance items. Additionally, planned downtime is considerably less because there are almost no planned maintenance items for the T7X,” said Odegaard.
To accompany the T7X, Bobcat will also introduce the world’s first all-electric attachments designed for specific tasks. The first to be developed include an electrically-powered auger to dig holes, an angle broom to sweep clean and a material-handling grapple.
While the new T7X is eco-designed, it is also a smart machine featuring software connectivity via two-way telematics communications. The platform provides integral data about equipment performance, along with operator-focused data to change machine preferences, tune the performance to certain job situations and upgrade product features. This includes variable drive speed at full torque and other features not possible with a diesel-hydraulic machine.
Doosan Bobcat has also announced a strategic partnership with South Carolina-based Sunbelt Rentals, a leading rental equipment company in North America with more than 1,025 locations. Through this partnership, Sunbelt Rentals committed to a significant investment in a large fleet of Bobcat T7X all-electric compact track loaders and electric compact excavators, which will be co-branded and made available in 2022. Sunbelt Rentals will be the first national equipment rental company to adopt Bobcat’s battery-electric technology and make it available to customers, supporting the environmental, social and governance (ESG) focus for both companies.