Battery Technology

In order to compare the vibration and noise exposure of STIHL’s battery-powered MSA 220 C and the combustion driven MS 201 C, a professional operator was monitored during a pre-commercial thinning operation in a twenty-year-old hardwood stand. The vibration levels were measured with a tri-axial accelerometer on the front and rear handle of both the chainsaws, and assigned to five different work elements using a video documentation. Additionally, noise levels were recorded in one-minute intervals, with a dosemeter worn by the operator. The results show that battery-powered chainsaws, when compared to combustion-driven chainsaws, can reduce the daily vibration exposure by more than 45% and the noise dose by about 78.4%, during pre-commercial thinning tasks. Replacing combustion-driven chainsaws with battery-powered ones is therefore generally recommended, to reduce occupational health risks for operators, in this respect. However, the daily vibration exposure of about 2.42 m/s2, caused by the battery-powered chainsaw on the front handle, is still very close to the daily exposure action value set by the EU directives for health and safety requirements. The daily noise exposure of 89.18 dB(A) even exceeds the upper exposure action value. Consequently, a further reduction in the vibration exposure during work is desirable. With respect to noise exposure, additional measures must be implemented for conformity with the current safety standards, making the use of hearing protectors mandatory for electric chainsaws, too.

Section: Operational Remarksmentioning

confidence: 99%

Vibration and Noise Exposure during Pre-Commercial Thinning Operations: What Are the Ergonomic Benefits of the Latest Generation Professional-Grade Battery-Powered Chainsaws?

Huber

Hoffmann

Brieger

et al. 2021

“…In recent years, the market for battery-powered tools in the green maintenance and forestry sector has been continuously increasing, reaching 51% of sales worldwide, and sales of tools with this power supply are expected to increase further [1]. Recent developments in battery technology have enabled the production of powerful, compact and lightweight manual tools even in the forestry sector [2,3], which has high demands on the power and reliability of the tools.…”

Section: Introductionmentioning

confidence: 99%

“…Recent developments in battery technology have enabled the production of powerful, compact and lightweight manual tools even in the forestry sector [2,3], which has high demands on the power and reliability of the tools. In the last few decades, the density energy of rechargeable batteries has increased ten times, passing from Ni-MH technology to modern Li-ion cells [1]. Nowadays, the most widely used batteries are lithium-ion ones, which have good energy and power density, durability, safety and a significantly reduced weight compared to older battery types [4].…”

Section: Introductionmentioning

confidence: 99%

“…Comparably no exhaust gases on site, easy maintenance and the absence of cables are other advantages of the battery chainsaws [21]. Despite these positive aspects, batterypowered chainsaws still show some drawbacks, such as insufficient battery capacity and the risk of overheating of the battery pack during hard work, with possible consequences on productivity [1]. Previous studies by Spinelli et al [22], Colantoni et al [23] and Engelbrecht et al [24] showed that in gardening and arboriculture activities, where branches and small trees often need to be cut, the battery chainsaw can be a viable alternative.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Comparing the Productivity of the Latest Models of Li-Ion Battery and Petrol Chainsaws in a Conifer Clear-Cut Site

Laschi

Neri

Marra

et al. 2023

The recent technological development of batteries has allowed the production of powerful tools that are also used in forestry operations. For this reason, this study aimed to compare the performance of two latest chainsaw models in a conifer clear-cut. The examined chainsaws, the battery-powered Stihl MSA 300 and the petrol-powered MS 261 C-M, have comparable power and weight. The overall working times were recorded and then gross, net and felling/processing productivities were quantified. Our findings reported that in a working day (7.4 h gross time), each chainsaw felled and processed an average of 20 trees of 0.64 m3 with an average diameter at breast height of 28 cm. Considering the net productivity, no statistically significant differences were recorded between the two chainsaws. Investigating the productivities on operations conducted using the chainsaws, the battery chainsaw showed a lower average tree-processing productivity than that recorded for the petrol chainsaw. On average, the battery duration was 0.88 h, while the petrol tank duration was 0.97 h. Our study shows that battery chainsaws have great potential in forestry operations; however, considering the actual need for 8 charges per standard workday, optimizing battery management is an important objective for future work.

“…Studies of ground-based hybrid or electric forestry equipment included hybrid tree harvester concepts and drivetrain studies by Rong-Feng [15] and Prochazka [16]. Electrified solutions already on the market include hybrid woodchippers, hybrid forwarders, and hybrid harvesters, discussed by Pandur [17]. Except for in slack-pulling carriages, hybridization and electrification is still in its infancy in cable-based logging equipment.…”

Section: Introductionmentioning

confidence: 99%

On the Design of Hybrid Tower Yarder Drivetrains: A Case Study

Leitner

Renzi

Spinelli³

et al. 2022

Meeting ever-tightening emission regulations and ambitious climate targets requires drastic efficiency improvements and emission reduction across all sectors. Hybridization as an intermediary step towards electrification is a prominent approach to achieve this. Within the forestry sector, most equipment still relies on conventional mechanical or hydraulical drivetrains. This work focuses on the design of hybrid tower yarder drivetrains, in order to facilitate the technological transition to more sustainable equipment. Tower yarder duty cycle data are extracted from the literature and organized into a set of reference duty cycle data via Matlab simulations. Based on typical performance requirements, various technological solutions are studied for the following key tower yarder subsystems: energy storage, winch drive, energy source, and energy dissipation. The objective is to determine the most performing design considering system cost, performance, weight, and durability. Challenging control considerations are discussed and control algorithms are presented. Further presented are drivetrain architecture alternatives to boost overall efficiency. The best hybrid drivetrain, based on a large set of operation data gathered from other studies, is finally subjected to design calculations and a case study involving a 5-ton tower yarder. Results indicate that off-the-shelf electric drives, reduction gearing, and energy dissipation systems can satisfy all performance requirements, including a maximum power of about 100 kW per drive. A 15–45 kWh power-dense battery pack or a 100 kWh energy-dense battery pack may be required to cope with a power of up to 70 kW RMS, pointing to a need for substantial overdesign and confirming that the energy storage system represents the largest design challenge. The engine should achieve at least 41.5 kW of power to compensate for combined average net energy consumption in the yarder. These results confirm the feasibility of tower yarder hybridization and the large potential for energy recovery. This is especially true in the closed-loop setup, with a recovered energy of up to 5 kWh per transport cycle. Finally, differences between the proposed optimal design and the commercial hybrid design by Koller Forsttechnik are discussed.