Battery Energy Storage System Powers Trailer City on Data Center Build

For phase one of a massive hyperscale data center build in Kansas City, Missouri, JE Dunn Construction, a leading general contractor, needed a sustainable way to power 24 jobsite trailers until grid power was available. The trailer compound would serve as the project’s primary office space. Power needs included heating and air conditioning, computers, lighting, security systems and refrigerators.

Given the project owner’s aggressive sustainability goals, running diesel generators 24/7 wasn’t ideal. While Tier 4 diesel generators run cleaner than their predecessors, the amount of carbon dioxide they emit is significant. United Rentals presented a cost-effective alternative for the customer’s consideration: a battery energy storage system (BESS) it developed in collaboration with Termaco.

BESS units provide practical sustainable power solution

The Termaco TREE 500kW battery is one of the largest rental batteries available. Pairing it with a generator creates a hybrid power solution that allows contractors to significantly downsize generators and slash generator run time. Cutting run time in turn curtails greenhouse gas emissions while reducing fuel consumption, equipment-related downtime and bothersome jobsite noise.

The battery powers the load until it needs charging, at which point it automatically turns on the generator. Charging takes only an hour. Once the battery is charged, it shuts down the generator. The TREE is pre-programmed with minimum and maximum charge settings, so no power interruptions occur during operation.

The general contractor was intrigued by the proposal and agreed to pilot the BESS in conjunction with a 275kW generator.

Generator runtime slashed by more than 85%

Over the course of seven months, the hybrid power solution performed flawlessly, with zero loss of power. The reduction in generator run time was equally impressive.

Instead of running 24/7, the generator ran for an average of 3.5 hours per day. Run time was reduced from 100% in the typical scenario to an average of 14.5%, with lows of 4.5% during milder weather. Over seven months, the solution reduced diesel fuel consumption by more than 54,000 gallons and greenhouse gas emissions by 464 metric tons.

The 464 tons of carbon emissions that the hybrid power solution saved is equivalent to the amount of carbon:

• Sequestered by 7,672 tree seedlings grown for 10 years.
• Sequestered by 465 acres of U.S. forests in one year.
• Avoided by recycling 39,443 trash bags of waste instead of sending it to a landfill.
• Emitted by the energy use of 62.3 homes for one year.
• Emitted by 108 gasoline-powered passenger vehicles in one year.

Generator maintenance reduced

Generators typically require service every 500 hours of run time. Minimizing run time also minimizes maintenance needs. Reducing generator servicing boosts sustainability by conserving resources such as oil. During service, the battery handles the load, eliminating downtime.

Wet stacking reduced or eliminated

When diesel generators are sized to meet peak power needs, during low-load periods they are vulnerable to wet stacking. This condition occurs when unburned fuel builds up in the exhaust system and causes deposits of vaporized fuel and soot to form. It can reduce performance in the short term and even cause the engine to stall under high loads. Over time, it can permanently damage the engine.

If wet stacking happens at night, refrigerators may lose power, security systems may go down and computers may lose data or fail to back up. If it occurs during the day and the HVAC goes down, morale may sink, and work may slow as everyone in the trailer awaits the arrival of a technician.

With a downsized generator paired with a BESS, the chance of wet stacking is greatly reduced.

Noise-free work spaces

Inside trailers powered by a diesel generator, the constant drone of a diesel engine can be distracting and stress-inducing. When the battery powers the trailer, meetings and calls take place in relative quiet.

Meeting evolving demands for long-term temporary power

Projects in remote locations once needed temporary power for one or two months. Today’s megaprojects often require it for one or two years. The environmental ramifications can be enormous. A hybrid power system reduces the environmental impacts of meeting long-term temporary power needs as well as the impacts on the bottom line.

United Rentals is committed to bringing innovation to the table during the bid process and delivering powerful wins for customers at every project phase.

JE Dunn, always seeking forward-thinking and sustainable solutions, embraced the opportunity to pilot a BESS on the jobsite, an innovative approach they had not previously used. Due to the tremendous success of the pilot, they plan to consider implementing the solution on future projects.

The United Rentals Power and HVAC team will be there to help. By engaging early in project planning and collaborating throughout the project, team members can recommend hybrid power solutions and assist with right-sizing them as the site evolves to efficiently drive down fuel costs and greenhouse gas emissions starting on day one.

Contact our Power & HVAC team to inquire about sustainable temporary power options for your next project.