Inside Innovation: Electrification of construction equipment creates a buzz on worksites

Two earth and material moving equipment industry leaders have made recent announcements that bring the electrification of the construction worksite closer to reality.

Doosan Bobcat North America, a global manufacturer of compact construction, agriculture and landscaping equipment, has joined with Green Machine Equipment Inc. of Buffalo, N.Y., to replace Bobcat’s standard diesel power source in its excavators with Green Machine’s proprietary battery technology. Sales begin in select markets later this year.

“Electrification is another step forward in our commitment to sustainability, as well as a technology that will allow our customers to work more productively, efficiently and cost-effectively,” Joel Honeyman, vice-president of Global Innovation at Doosan Bobcat said in a media release. The electric hydraulic machines promise to provide power and performance equal to the diesel-powered version, with lower operating costs, zero emissions, reduced noise and minimal maintenance.

Bobcat will send their standard diesel-powered equipment to Green Machine, who will then install their lithium battery technology. Although Green Machine has historically rented and sold similar electric retrofits of other brands under its own label, this partnership will reportedly retain the Bobcat branding.

Meanwhile, Volvo Construction Equipment last month announced the opening of its North American order book for two of its compact electric machines — the Volvo ECR25 electric excavator and L25 electric wheel loader.

Pre-booking, now available to customers in the U.S. and Canada, expands Volvo’s successful launch earlier in the year of these excavators and wheel loaders in key European markets. After signing up, North American customers will be alerted if they have been selected to complete an order for the machines. The first deliveries are expected in June 2021.

Both companies are addressing increasingly strict emissions regulations being adopted in Europe and North America. Starting with smaller equipment makes sense, given the complexities of integrating electric drivetrains into existing hydraulic systems. Nevertheless, it will result in product release cycles that could take a few years over the full line-up of products.

The partnership between Bobcat Doosan and Green Machine allows Bobcat to jump-start its electrification development in tandem with Green Machine’s expertise in power technology retrofits. That’s important considering the high stakes for Bobcat in the competitive small equipment marketplace, versus Volvo’s vast corporate resources that can offset electrification development costs.

Wide customer acceptance of electrified construction equipment rests largely on the performance of lithium batteries, specifically recharging times and useful time range.

Volvo says its ECR25 mini excavator and L25 compact wheel loader will have onboard chargers that enable overnight charging adaptable to conventional household electrical systems, plus an off-board fast-charger that requires a three-phase outlet. Using the fast-charge option, the ECR25 can reach 80 per cent power within only one hour of charge time, and the L25 within two hours of charge time.

The recharge time for the Bobcat/Green Machine 17e mini excavator prototype unveiled in March 2020 is said to be only four hours, with a run time of eight hours at full capacity, longer under lighter strain. The prototype S70e skid steer reportedly requires a six-hour charge for eight hours of operating life.

However, neither Bobcat nor Volvo is yet offering the next logical step — a fully electric machine. The lithium powered machines will continue to rely on hydraulics rather than electric motors for the heavy work. While this has the advantage of retaining the operational feel of the diesel-powered models, it does not meet the long-term goal, shared by many manufacturers, of all-electric machines dominating the worksite.

Industry observers say that an all-electric machine with electric actuators instead of hydraulics would not depend on a large or small engine to control breakout speeds and lifting capacities. That would be determined instead by complex computer coding. The potential would then exist for manufacturers to build fewer models that would be programmable by dealers to meet their customer’s capacity requirements and budget.

Nevertheless, several manufacturers have all-electric prototypes in the field today, with product rollouts planned over the next few years.