Electric Construction Equipment

---

Electric Off-Road Equipment, or Electric Heavy Equipment is off road equipment often used for construction and mining that is primarily powered by batteries or direct electrical connections. Traditional heavy equipment includes machines such as excavators, bulldozers and wheel loaders. Heavy machinery is typically powered by diesel engines and is the primary producer of harmful contaminants such as greenhouse gases and particulate matter during operation. In contrast, electric heavy equipment is able to be powered by lithium ion batteries which do not produce environmental contaminants during usage. The use of a battery instead of a traditional combustion engine also significantly reduces construction noise and vibration, which can be beneficial to worker health and safety. Currently, the majority of electric off-road equipment is either compact excavators or small wheel loaders. However, ideas for larger pieces of machinery have been proposed.

History

The first piece of electric off-road equipment ever created was a dragline excavator by Vulcan Ironworks of Toledo, Ohio, in 1919. This excavator was developed as an alternative to steam-based machines which were common to the time period. The lack of sufficient batteries required that either an offboard energy source or on-board gas generator be provided for operation. As fossil fuels proved to be the more efficient source of power, electric machinery was largely put aside. However, with recent advances in battery technology, fully electric equipment has been reconsidered. Companies have begun investing in the research and development of battery electric off-road equipment. Volvo released the first electric mini-excavator in 2019 and it began commercial sales in 2021. Since 2019, many different companies have released competing models, and some have begun developing larger prototypes to be released in the future. These advances have not been limited to just excavators, but several different types of equipment.

Categories of Equipment

Dragline Excavators

The oldest form of electric off-road equipment is the electrified dragline excavator. Since their introduction by Vulcan Ironworks in 1919 it has been common for dragline excavators to use both AC and DC motors to operate the cable systems which control dragline operations. There has been a large shift towards using AC motors over the past 20 years due to its more robust and reliable setup Many dragline excavators not only use electrical power for control of the bucket and boom, but also for crawler operations. Due to the required power output to operate these large machines, which can have an operating weight approaching 8000 tons in some units, relying on battery operated systems is not feasible. For example, the Komatsu P&H 9020C has 20 separate AC motors rated at 690 volts

Compact Excavators

The most common form of electric off-road equipment is the mini-excavator or compact excavators, which are categorized as having an operating weight under 10,000 lbs, or 5-tons. Compact excavators are smaller excavators which require less energy than traditional machines, making them ideal for the introduction of battery powered systems. Volvo was the first original equipment manufacturer (OEM) to produce a battery powered compact excavator, unveiling their ECR25 model at Sauma 2019. These models replaced the traditional diesel powered engine with 48v lithium ion batteries which power all of the systems in the machine, including the hydraulics used to manipulate the bucket and attachments. The ECR25 is capable of maintaining a charge for eight hours before it must be recharged overnight, which can be done through a connection to a simple household outlet. Since the introduction of this machine Volvo has also introduced two smaller electric mini-excavator models, the ECR18 class. Other original equipment manufacturers producing electric compact excavators include Caterpillar, JCB, Bobcat, Wacker Neuson, and Komatsu.

Mid Sized Excavators

The next step up in electrified excavators is mid sized class machines, which have an operating weight greater than 10,000 lbs (5 tons) but generally less than 90,000 lbs (45 tons). While battery powered excavators of this size have yet to be released for consumer purchase, many have been unveiled over the past several years. Komatsu has recently partnered with battery manufacturer Pantera to develop the PC-210E, a 20 ton class machine with a maximum power output of 123 kw and a battery capacity of 451 kwh . Similarly, Caterpillar Inc has unveiled a 26 ton mid-sized battery power excavator, the 320 Electric. This machine is powered by a 256 kwh battery and has an estimated runtime of eight hours on a single charge and is expected to be released for sale in Europe and Japan in 2023. Volvo is also working on a mid-sized excavator, more specifically working to electrify its EC320 class of excavator.

Wheel Loaders

Wheel loaders are another popular class of machine which has been converted to a battery powered electric system. Volvo is the first large manufacturer to produce electric wheel loaders available for purchase, with their L20 and L25 machines becoming available in 2022 . Caterpillar has also recently unveiled an electric wheel loader, their 950 GC model, which has a 320 kwh battery and is capable of operating for up to six hours on a single charge. Wheel loaders are another popular form of electric off-road equipment

Mining Trucks

In late 2022, Caterpillar unveiled its first battery electric powered mining dump truck, the prototype 793. This completely battery operated truck was developed in association with several mining companies as part of Caterpillars early learner initiative. The truck was able to traverse a seven kilometer course while fully loaded to its rated capacity. It was also able to traverse one kilometer at both a +10% grade and a -10% grade, while recapturing heat to recharge batteries on the latter. Upon completion of the seven kilometers, the truck retained enough charge to complete several full cycles.

Environmental and Workplace Impact of Electric Equipment

Noise Reduction

The reduction of construction noise provided by electric equipment can have significant health benefits for construction workers and reduce jobsite impacts on surrounding areas. According to the United States Occupational Safety and Health Administration, noise during construction has been known to cause hearing damage, primarily hearing loss due to equipment noise. OSHA references a study published in the American Industrial Hygiene Association in December 2002 which states that over a half a million construction workers are exposed to harmful noise levels during construction operations . As it relates to construction equipment, this study found that all equipment operators experienced an average noise value of 75 decibels over the course of a typical 8-hour work day. Of the approximate 5 million constructions workers employed at the time, this study found that over 750,000 of them were exposed to over 85 decibels throughout their daily activities. Electric equipment does not produce noise emissions to the same degree due to the electric motor, however noise from the hydraulic machinery can be heard.

Reduced Emissions

Diesel fuel emissions are a concern for the health of workers, as well as the health of the environment. These health risks primarily come from the production of harmful chemicals like carbon dioxide, nitrous oxides, and particulate matter during the combustion of diesel fuels. Off-road equipment emissions can vary depending on the machine and its application, however machinery is likely to produce two to three times the level of emissions in rough terrain. In mining operations, over 40% of all energy expenditures go towards ventilation for workers . These expenditures and health risks are causing mining corporations to increase investment in new electric technologies, which can reduce fuel consumption and subsequent emissions.

Cost of Electric Equipment

Due to the large size of the batteries present in electric equipment and the valuable materials within, the cost of a piece of electric equipment can cost on average 2-3 times that of its diesel counterpart. However, reduced maintenance costs can have an impact on the total lifetime cost of the machine, which in time can counteract the large initial costs.

Charging Time

Commercially available models often require an overnight charging period to return to full battery. Many can be plugged into a normal 120v wall outlet, however this can take between 6-8 hours. Many companies, such as Volvo, are working to develop fast charging systems for their new machines

Industry Outlook

Interest in electric equipment is on the rise, and newer prototypes with greater abilities are being developed around the world. The value of the electric construction equipment industry is expected to grow from 9.2 billion dollars in 2022 to 24.8 billion by 2025. There are particularly large financial incentives for mining corporations. Over 40% of energy expenditures during mining operations are generated from ventilation costs, due to diesel machinery operating in tight conditions as well as particulate matter. This provides a financial incentive for these corporations along with an existing incentive from net zero energy commitments.

Manufacturers

• Volvo Construction Equipment
• Caterpillar Inc.
• Komatsu Limited
• JCB
• Wacker Neuson
• Hitachi
• Doosan
• Hyundai LE
• Schaffer Maschinenfabrik

References

This article "Electric Construction Equipment" is from Wikipedia. The list of its authors can be seen in its historical and/or the page Edithistory:Electric Construction Equipment. Articles copied from Draft Namespace on Wikipedia could be seen on the Draft Namespace of Wikipedia and not main one.

---