BESS codes, constructability and safety require technical, regulatory insight: 10 tips from an EPC

Here are 10 insights for effective project delivery in today’s ever-evolving battery energy storage environment.

1. Engage early with the AHJ

It’s stating the obvious, but having early conversations with local fire officials or building codes departments can alleviate many later complications. These authorities having jurisdiction (AHJs) must review and approve plans that comply with fire, electrical and building codes, Bear in mind that some AHJs may have requirements that deviate from national codes.

The pace of adoption of codes and standards can vary by jurisdiction and the AHJs can deliver important insights into their expectations for meeting applicable codes. Early conversations will provide clear guidance that help to smoothly navigate the project’s permitting and inspection process. These conversations are likely to focus more on the specifics of the codes and standards that must be met, without any direct recommendations on specific safety or fire suppression systems to be installed.

These early conversations, however, will help the developer or owner make important decisions. These interactions can become a two-way street that helps the AHJ to get comfortable with the types of systems being installed in the jurisdiction, so that first responders will have all the information they need if the worst happens.

2. Fire test data matters

UL 9540A and CSA-800 are two of the leading testing protocols that are driving much of the site design and hazard mitigation approaches that are so crucial to BESS projects getting approved. The real-world large-scale fire test (LSFT) and explosion data produced in accordance with published testing protocols will inform more than compliance.

This data is at the heart of risk mitigation for the project, and it will be relied upon heavily by the AHJ to evaluate design decisions. Without this data and associated hazard analyses to fall back on, an AHJ could impose excessive spacing, ineffective suppression systems or other requirements that would impact cost and/or schedule.

The AHJ will dictate the rules of engagement and will want to see that the project is in compliance with applicable codes and standards by the time ground is broken. Normally, there is not a long runway between the time first conversations with the AHJ begin and when procurement decisions are made. The risk of mistakes can be mitigated with complete and detailed fire test data.

3. Codes and standards are moving targets

City or county websites should not be viewed as the single source of truth, due to the possibility that some information may be outdated. Instead, try to schedule a conversation with appropriate codes officials or other AHJs to verify whether their requirements align with industry-recommended practices, such as those provided by NFPA 855. Keep in mind that these, too, are rapidly evolving, so staying plugged into the code development process is critical for future projects.

There are cycles in terms of the codes that can vary from one year to as long as four years. This means that not every entity has adopted the same thing. NFPA 855 is the acknowledged authority stipulating requirements for BESS facilities. However, there are currently only a handful of states that have adopted those standards.

Most states have adopted the I codes — IBC and IFC — and the intent is that the NFPA and I codes mirror each other on different cycles. The risk is that with both standards in circulation, the AHJ may pull in a mix of requirements as necessary.

This means that for some projects it’s possible to have different codes really aiming to accomplish the same objective. Added complexity is often the result.

4. Thoroughly and thoughtfully levelise bids

It has become common for some bidders to reduce initial project costs by complying with bare minimum requirements of outdated local codes. Any initial cost savings from that approach could quickly be offset by change orders and project delays resulting from the need to comply with new requirements as they evolve.

Experienced engineers on staff with reputable OEMs and EPCs will generally provide a higher level of experience that helps an overall project avoid inadequate or unsafe designs and provide surety of project outcomes.

Executing projects end-to-end with contractors that bring both good and bad firsthand experiences to the table can help inform the process. This knowledge results in accurate specifications for all the products, a key factor behind schedule and pricing certainty.

5. UL 9540 isn’t optional

OEMs must perform reliability evaluations and conduct a variety of safety tests to get a product listed to UL 9540. These evaluations are essential aspects of due diligence and owners should require this documentation as part of any battery supply agreement.

Forthcoming updates to NFPA 855 may include a retroactivity trigger, subjecting legacy projects to UL 9540 requirements and evaluations. This could have consequences.

Legacy projects from seven years ago that weren’t listed to UL 9540, may mean that the door is opened for the AHJ to audit the site. If the components and configurations are not compliant with current standards, the AHJ may require the owner to make fixes that bring the operating facility up to current standards. Substantial retrofit costs could be incurred.

About the Authors

Andrew Early, PE, is a preconstruction manager for energy storage projects at Burns & McDonnell. He specialises in BESS project definition and preliminary engineering with an emphasis on consulting with manufacturers and clients for codes and standards compliance pertaining to NFPA 855, UL 9540 and UL 9540A.

Ben Echeverria leads energy storage regulations and compliance efforts at Burns & McDonnell. He has worked in the power generation market for most of his career, focusing on electrical controls and instrumentation for fire protection and life safety. He actively participates in the codes and standards consensus boards specific to energy storage at grid scale.