By Sara Vincent, Director of Marketing, JLG
A few years ago, Barrie Lindsay, JLG’s Director of Engineering - Europe, spoke to IPAF (the International Powered Access Federation) on the topic of sustainability and what it means for access equipment. Because his message of “Operating Sustainably, Transforming Tomorrow” is still relevant in today’s marketplace, here are some thoughts from JLG on how sustainability will influence the future of electrification in the industry.
What is Sustainability?
Sustainability is most often described as “saving the planet” or “climate change” and is a concept that recognizes that the environment is an exhaustible resource.
The environment is, of course, a vital element of sustainability, but sustainability is also made up of economics and social (informally, the three pillars of sustainability are called: planets, profits and people). This means that in addition to natural resources, we also need social and economic resources.
Sustainability and the Aerial Industry
Looking at sustainability from an aerial industry perspective, improving air quality by reducing machines’ CO2 emissions will significantly contribute to protecting the environment.
As an original equipment manufacturer (OEM), this means that JLG shares in the responsibility to utilize sustainable resources as much as possible in the design, manufacture and marketing of eco-friendly aerial access products. Sustainability guides our responsibility to our customers, who are demanding “green” solutions that meet new and evolving legislation and guidance on greenhouse gas and particulate emission reductions.
So, how can we as a manufacturer respond to the growing pressure our customers are getting from local, regional and country governments for more sustainable job sites? By saying “yes” to electrification.
Adoption of Electrification
Electrification is the conversion of a machine or system from generating energy from fossil fuels to the use of electrical power. Aerial equipment OEMs like JLG have been offering electric machines for more than two decades. Since the early 1990s, JLG has been developing and introducing new technologies, such as hybrids and fuel cell-powered machines, to advance the electrification movement. For example, historically, these machines have performed best in non-rough terrain applications, like on slab concrete.
In addition, most modern electric and hybrid machines still have traditional hydraulically powered actuation and lift systems. However, today customers expect electric vehicle performance to rival that of internal combustion (IC) equipment, including diesel-powered machines, and electrification technology is rapidly evolving to extend beyond the drivetrain to functions traditionally powered by hydraulics.
This means that the aerial industry has finally started its transition to fully electric machine functionality, eliminating the reliance on hydraulics and fuel systems thereby becoming more sustainable.
Electrified Products
The electrification of equipment doesn’t happen overnight. It’s a journey requiring a long-term commitment from OEMs, rental equipment providers and end-users to change their expectations and behaviors in ways that will increase the utilization of sustainable, eco-friendly machines on job sites.
Let’s take a look at the technologies being developed as part of the electrification journey, including:
Improving equipment battery performance has been an ongoing technical challenge for many decades. Batteries have generally competed with internal combustion engines as the power source of choice. The selection of battery-powered machines was largely dependent upon certain environmental factors, such as working indoors.
In general, each technology has had its place in product development. The lines have become blurred in the last few years due to more focus on the climate. There is an increasing expectation that zero emission solutions can replace internal combustion technology in areas where it has traditionally been dominant.
This has created a new challenge for the battery industry to develop and produce new technologies that can match the energy performance of IC engines. Today, this is still a long way off.
However, advances in lithium-ion (li-ion) battery technology are beginning to make this possible. For example, automotive development of battery chemistry and cell design is now being adapted for the off-highway industry.
What is a Li-ion Battery?
A lithium, or li-ion, battery is an electronic module consisting of several parts.
First is the battery cell itself. Generally, li-ion batteries are described as three different types: Prismatic, Cylindrical and Pouch. The different formats were designed at different times to increase the energy density of the complete pack. Individual cells are joined together in various configurations to create specific battery module voltages and capacities in each type.
For example, the same type of battery cells is used to power trains, buses and cars — just more or fewer cells are needed, depending upon the amount of power required to run the vehicle.
The second is the battery monitoring system and electronic controls. All the individual cells in the battery pack need to be controlled by a monitoring system. This system controls the discharge and charging of the batteries, as well as monitoring the cell health. Modern battery monitoring systems (BMS) will provide data on these functions, as well as have real-time reporting of problem codes to the machine’s control system.
Third is the enclosure in which the components are all mounted. The electronics and cells in lithium batteries need to be housed in a robust enclosure. In theory, using this technology, you could create an infinite number of battery shapes and sizes. When designed as replacements for existing flooded lead-acid (FLA) batteries, they will generally follow a standardized form factor. When developing new machines as an OEM, we have the opportunity to create enhanced value and performance in a new battery design.
However, moving to Li-ion as the power source poses a new problem as this technology is still costly compared to flooded lead-acid batteries. So, JLG set out to explore ways to reduce the total power consumption of a machine so that only one battery would be needed.
Energy Recovery
Looking for ways to make JLG products more sustainable, JLG engineers realized that they were able to replace all the hydraulics with electric actuators and utilize the robustness and energy density of lithium battery technology.
How so? While li-ion batteries provide similar cycle performance to FLA batteries, with less energy, its technology also makes it possible to recover energy from the machine (in the case of aerial equipment, when the machine’s platform is lowered) to reduce the number of batteries the machine requires to generate the necessary power.
Here’s how: Replacing the hydraulic cylinder on a typical scissor lift with an electromechanical lift actuator captures energy when lowering the platform by taking the rotational motion of the motor and turning it into a generator that charges the battery during the lift-down process.
Simply: As the machine lowers, it spins the motor, which creates electric energy, putting that energy back into the battery.
Common Machine Components
The electrification of equipment goes beyond the machine’s batteries. It includes common machine components like the motor, the control system and the actuators.
Motor technology has generally been driven by the need for improvements in efficiency, reliability, and TCO Technology development paths, including DC motors, AC motors, and permanent magnet motors. Permanent magnet motors generate torque and create motion to spin the motor. It is estimated that permanent magnet performance can increase the efficiency of a motor by up to 20-30% on average.
Motors with permanent magnets boast a long life and require zero serviceability. For these reasons, newer all-electric machines will most likely be powered by permanent magnet motors. They are more compact and powerful than other electric motor options, and they can be configured to deliver the increasing power requirements of larger machines.
Also directly related to electrifying a machine’s power and drive systems is advancing the development of control system technologies. Integrating smart controllers with the machine’s lift, drive and steer functions, combined with machine connectivity, enables precise monitoring and control of machine systems. New software is being developed to optimize operational efficiency while monitoring system health to allow for early intervention if a fault is detected.
As the industry electrifies, there will be an increasing focus on machine design for energy efficiency. An area that will continue to see further development is actuators. Replacement of hydraulic cylinders with electric linear actuators will improve efficiency with opportunities for energy recovery back into the battery. The application of these actuators is currently limited by lifting performance and cost. So, we will see hydraulic actuators being used for some time to come.
As energy on the machine becomes a premium factor, we will need to utilize more lightweight structures and components to reduce the energy required to put people at height.
Charging
In the electric product eco-system, a combined approach of good battery energy density and
fast charging is needed. As you may expect, where using IC engine equipment has been the norm, there has not been a need to develop an electric charging infrastructure, e.g., many early phases of building construction before utilities are laid.
So, in addition to advancing battery technology, there is increasing interest in developing innovative battery charging technology.
Today, electric construction machines rely on on-machine chargers plugged into the general site supply of 110V or 220V AC. Most of these on-machine chargers are single-phase, and they are inadequate for fast charging, especially as the machine’s battery packs increase in size. A three-phase 415V supply significantly reduces charging time but requires an additional 3-phase charger on the machine.
Automotive charging systems can also offer direct DC charging from the charging point, but this type of faster charging will require further investment in standardized charging infrastructure on-site.
This means that to be successful with electrification, the industry will need to collaborate on a new construction site charging infrastructure to fully exploit the advantages of modern battery technology.
With li-ion batteries, the equipment can be fully charged in only a few hours compared to traditional electric-powered lifts that require up to three times longer to charge, increasing machine utilization throughout a workday. And for additional productivity gains, lithium batteries can also be opportunity charged in a matter of minutes. But as mentioned previously, this technology is still more expensive than DC and AC options; therefore, the pace of adoption will only accelerate as technology advances and costs come down.
The Future of Electrification
The journey to electrification is complex, and success will depend upon engagement and adoption throughout the eco-system. Key issues revolve around developing new partnerships to create opportunity and value.
Changes in working practices and charging infrastructure are essential to utilize the potential of technology. All involved need to align with the purpose and value of electrification to the broader society.
Lift & Access is part of the Catalyst Communications Network publication family.
