United Rentals Powers Seventeen Office Trailers with a 250 kW Battery Energy Storage System (BESS)

United Rentals deployed the POWRBANK MAX, a high-capacity Battery Energy Storage System (BESS), to power a large complex of seventeen office trailers on a major construction site — reducing generator runtime by 78%, saving nearly 7,500 gallons of diesel, and cutting CO2 emissions by 168,000 lbs. in just 2.5 months. 

Challenge: Cutting Fuel Use for a Large Trailer Compound 

A large construction site operated a complex of 17 office trailers serving as the project’s administrative center. Each trailer required electricity for heating, cooling, lighting, and computer equipment. 

Winter conditions could push total demand to 250 kW, but during summer, the average load hovered near 30 kW. To cover occasional winter peaks, the setup relied on a 175 kW generator running 24 hours a day. This oversized setup meant the generator burned fuel continuously while often delivering only a fraction of its capacity. 

The result: excessive diesel consumption, high operating costs, constant noise, and significant greenhouse-gas emissions. 

Solution: High-Capacity POWRBANK MAX Battery Energy Storage System 

United Rentals partnered with POWR2 to deploy the POWRBANK MAX, a large-scale mobile BESS engineered to deliver high output when needed while dramatically reducing generator runtime. 

Instead of operating continuously, the generator runs only two to three hours per day – just enough to recharge the POWRBANK MAX’s batteries. For the remaining 21 hours, the trailers run silently on stored energy.  

If winter temperatures trigger all heaters simultaneously, the POWRBANK MAX can still provide up to 250 kW of power without interruption. 

Stephen Whitcomb, the POWR2 technician overseeing installation and commissioning, summarized the shift: “Now the generator charges maybe two hours a day, maybe three, and the whole rest of the time it’s just battery.”

Operational Advantages of Deploying the POWRBANK MAX 

Switching from an oversized generator setup to a hybrid setup with the POWRBANK MAX Battery Energy Storage System (BESS) delivered immediate benefits. Each improvement not only reduces costs but also site efficiency, safety, and sustainability.  

Streamlined Fuel Logistics

With the POWRBANK MAX handling the site’s primary power needs during low-load periods, diesel deliveries dropped sharply. Fewer refueling runs simplify logistics, reduce heavy truck traffic, and lower the risk of on-site fuel spills. This leaner fuel schedule cuts transport emissions and administrative time spent coordinating deliveries.

Lower Maintenance and Operating Costs

Reducing generator runtime directly translates to less wear and tear on expensive engine components. With fewer operating hours, service intervals stretch further apart, minimizing downtime and maintenance expenses. Over time, this extends the useful life of generators and BESS assets, ensuring a higher return on investment.

Quieter, Safer Work Environment

Traditional diesel generators produce constant noise and vibration that can disrupt nearby offices, residents, and crews. In contrast, the near-silent operation of POWR2’s POWRBANK MAX BESS creates a quieter, safer, and more productive jobsite. Lower decibel levels enhance worker focus and meet increasingly strict noise compliance regulations in urban construction zones, events, and sensitive environments such as schools or hospitals. 

Remote Monitoring and Control with ADVANTAGE by POWR2

The ADVANTAGE battery energy management software provides full visibility into site power performance. Through a secure web dashboard, managers can track real-time energy consumption, battery charge levels, and generator activity—from any device, anywhere. Automated alerts and remote start/stop controls enable faster response times, optimize generator scheduling, and ensure uninterrupted power delivery. This level of digital oversight reduces on-site supervision costs while improving accountability and decision-making through data-driven energy management. 

Quantifiable Results After 2.5 Months 

In less than three months, this setup prevented emissions equivalent to the annual carbon footprint of more than a dozen passenger cars and saved nearly $30,000 in fuel costs. 

Broader Impact 

The success of the POWRBANK MAX illustrates that large, multi-office construction operations can maintain full reliability while sharply reducing costs and emissions. 

“Less fuel burned means less traffic on site, fewer spill risks, less noise, and a better relationship with the client. It shows that we’re not just doing the job, we’re doing it responsibly and with intention.” 

Emma Seymour, Regional Product Development Manager – Sustainability, United Rentals 

The project provides a model that can be replicated for similar large-scale operations, where battery energy storage can handles heavy, variable loads. 

Conclusion 

The POWRBANK MAX transformed a fuel-heavy power setup into a highly efficient, low-emission solution. 

By cutting generator runtime by 78% and eliminating more than 7,000 gallons of diesel consumption in just 2.5 months, the system delivered substantial cost savings and a major reduction in environmental impact, without compromising the reliable power required for a complex of 17 office trailers.