News & Events

Navigating the Journey to Sustainable Off-Road Work Sites

Written by ZAPI GROUP | July 15, 2025

Insights from Dr. Ray Gallant, Vice President of Sustainability and Productivity Services at Volvo Construction Equipment.

The demand for more sustainable practices is reshaping industries globally, and off-road applications are no exception. From construction sites to mining operations, the drive towards decarbonization and efficiency is compelling. At the recent Future of Electrification 2025, Dr. Ray Gallant, Vice President of Sustainability and Productivity Services at Volvo Construction Equipment, outlined the critical steps and considerations for achieving truly sustainable off-road work sites.

The Foundation: Balancing the Three Pillars of Sustainability

Dr. Gallant emphasizes that sustainability is fundamentally about balance, resting on three interconnected pillars: social, environmental, and economic. While environmental aspects, such as carbon emissions and greenhouse gases, often dominate headlines, they represent only one part of the equation. Social sustainability focuses on being a good employer and community member, while economic sustainability ensures that solutions are viable and allow companies to develop and implement them without financial ruin. All three must be kept in equilibrium for any long-term success, viewing sustainability as a continuous journey rather than a fixed destination.

Driving the Shift: Technologies and Solutions

Achieving sustainable work sites involves a three-step transformation: developing enabling technologies, establishing a robust refueling/charging ecosystem, and optimizing site operations for energy efficiency. Historically, diesel fuel has been a remarkably convenient and energy-dense solution, but its widespread use has led to wasteful energy practices. The shift demands a smarter approach to energy utilization.

Dr. Gallant identified five core sustainable power solutions emerging in the off-road sector:

  1. Battery Electric: Already appearing in compact machines and moving into mid-level equipment like 20-ton excavators and 5-cubic-yard loaders. Smaller machines often use 48V systems, leveraging existing forklift infrastructure, while larger machines transition to 600V for faster charge/discharge rates, not necessarily higher energy density per pound.
  2. Alternate Fuels: Biodiesels and renewable diesels offer immediate carbon reduction for existing diesel machines.
  3. Grid-Connected Machines: Ideal for stationary applications, drawing nearly unlimited power directly from the grid.
  4. Hybrid Solutions: Combining power drives (e.g., smaller diesel engines running generators to charge batteries, using electric motors for boosts) or electrifying attachment systems for greater efficiency.
  5. Hydrogen: Including fuel cells or hydrogen combustion, viable for very heavy applications but requiring significant infrastructure investment for production and storage.

The choice of technology heavily depends on the machine's power requirement and daily hours of use. For instance, battery weight is a crucial factor, though it can sometimes replace a counterweight in certain machine designs. Volvo CE currently offers commercialized 48V battery electric machines and is expanding its mid-range offerings. To support these diverse charging solutions, from mobile power packs to containerized fast chargers, are being deployed to minimize machine downtime on remote sites.

Real-World Impact: The California Pilot

To illustrate the tangible benefits, Dr. Gallant shared insights from a pilot project involving a mid-size electric excavator in Southern California. A key finding was the stark difference in emissions: 94% of a heavy equipment machine's total greenhouse gas emissions occur during its operational life, with only 6% attributed to manufacturing. This underscores the importance of focusing on the power source and energy consumption for meaningful carbon reduction.

In the 122-hour trial, the electric excavator achieved an impressive 80% reduction in CO2 emissions compared to its diesel equivalent, even when considering the carbon intensity of the California grid. This single electric machine was equivalent to taking about 13 cars off the road in terms of carbon impact. While electric machines have a higher embedded carbon footprint (around 28% more initially), this is offset within approximately 800 hours of use, with the machine's entire carbon footprint (manufacturing and operation) offset by around 4,000 hours, or roughly two to two-and-a-half years of operation.

Beyond the Environment: Economic Viability and Site Optimization

Beyond environmental gains, the economic case for electrification is strengthening. The California trial showed an 82% reduction in fuel costs for the electric machine compared to its diesel counterpart. Furthermore, electric machines are estimated to have significantly lower repair and maintenance costs, primarily due to fewer fluids and wear parts. Even factoring in a battery replacement around 12,000 hours (a very conservative estimate, as batteries are expected to last 16,000-19,000 hours in first life), the lifetime repair and maintenance savings remain around 6%, in addition to a 100% elimination of DEF costs. Over a 20,000-hour lifespan, an electric machine can result in approximately 15% cash flow savings, translating to roughly $150,000 on a typical $1 million operating cost for such a machine. With a 20% incentive, these savings could jump to nearly 25% from day one.

The journey towards sustainability also involves optimizing the entire work site. Volvo CE's "Electric Site Trial" demonstrated the power of combining sustainable power with digital technologies, AI, and automation. By replacing six diesel units with eleven electric and autonomous machines (including a hybrid loader, grid-connected excavator, electric crusher, and eight smaller autonomous haulers with frequent 1-minute opportunity charging) and reducing operators from six to three, the trial achieved a 98% CO2 reduction and 40% lower operating costs. This optimized approach also significantly improved site safety due to autonomous operations and restricted human presence near machines. Dr. Gallant concludes that energy management is the ultimate key to a truly sustainable and productive site.

Key Takeaways

  • Holistic Sustainability: Sustainable off-road operations require balancing social, environmental, and economic pillars, with economic viability being non-negotiable for long-term success.
  • Diverse Power Solutions: No single solution fits all; battery electric, alternate fuels, grid-connected, hybrid, and hydrogen each have their specific applications based on power demands and duty cycles.
  • Operational Emissions are Key: Over 90% of a machine's lifetime emissions occur during operation, highlighting the crucial role of power source and energy management in decarbonization efforts.
  • Strong Economic Case: Despite higher upfront costs, electric machines offer significant lifetime savings in fuel, maintenance, and DEF, making them economically viable, especially with incentives.
  • Site Optimization for the Future: Combining sustainable power with digital, AI, and automation can revolutionize site productivity, safety, and energy efficiency, pushing CO2 reductions close to 100%.

Navigating the Path Forward

Despite the clear advantages, widespread adoption faces challenges, including the initial higher purchase cost (around 70% more than diesel) and the need for operational changes, such as adjusting charging schedules. However, innovations in financing are emerging, with companies recognizing the second-life value of batteries for applications like grid backup, which can improve financing terms for customers. The industry is also moving towards a holistic approach, considering electric attachments and designing future machines specifically to leverage electric drive capabilities, such as instantaneous torque and high RPMs, rather than merely replacing diesel engines. Volvo CE currently utilizes both NMC/NCM and LFP battery chemistries, adapting to specific machine designs and duty cycles, while continuously exploring new technologies like sodium and solid-state batteries. As Dr. Gallant aptly puts it, "Faith in the future gives us power in the present," signaling a hopeful and determined path forward for off-road electrification.

To learn more, watch the full session here: