Battery Storage (BESS) Design Services

Battery energy storage (BESS) design has become one of the most complex and heavily regulated segments of solar engineering. NFPA 855 fire code compliance, NEC Article 706 electrical requirements, UL 9540 product listing verification, and the specific integration decisions between AC-coupled and DC-coupled architectures make solar plus storage design a specialty that most solar companies struggle to staff in-house. RIH Engineering delivers battery storage design services as an outsourced BESS design partner for US solar EPCs, installers, and developers scaling into solar plus storage.

What you get

• Complete BESS electrical design compliant with NEC Article 706 (Energy Storage Systems)
• NFPA 855 fire code compliance documentation including setbacks, ventilation, fire detection, and signage
• UL 9540 and UL 9540A product listing verification for all specified equipment
• AC-coupled or DC-coupled architecture design (per your customer preference or system requirements)
• Battery sizing calculated against customer backup needs, peak shaving goals, or time-of-use arbitrage
• Protected loads panel design for backup-capable systems
• Rapid shutdown integration coordinated with solar PV system per NEC 690.12
• Signage and hazard identification per NFPA 855 and NEC 706
• Complete plan set including electrical, structural mounting, and fire code compliance documentation

What we handle for you

BESS design touches multiple code jurisdictions simultaneously: electrical (NEC 706), fire (NFPA 855, IFC), building (IBC), and product listing (UL 9540). Getting all four right on the same project requires expertise across all four domains, which most solar companies don't have in-house. The result is either avoiding BESS projects entirely or delivering them slowly with high revision cycles.

We take BESS design off your plate as a complete package. You send us the project requirements, customer backup or peak shaving goals, and site conditions. We come back with a full BESS design including electrical, fire code compliance, structural mounting, and signage, ready for AHJ and fire marshal review.

The cost of doing this in-house

BESS projects fail permit submissions at rates 2 to 3x higher than PV-only projects, mainly because fire code and NFPA 855 requirements are unfamiliar to solar teams. Each failed submission means weeks of delay, damaged AHJ and fire marshal relationships, and customers watching your team struggle with what looks like a straightforward addition.

Meanwhile the solar+storage market is growing 40 to 60 percent per year in the US. Companies that can't deliver BESS quickly are getting priced out of the fastest-growing solar market segment. Every quarter you delay building BESS capability is a quarter of missed pipeline.

Why RIH Engineering is safe to try

Send us one BESS project. We deliver the complete design in 5 to 14 days depending on complexity and jurisdiction. You compare the deliverable against what your in-house team could have produced. If it doesn't meet your bar, we adjust. No long-term commitment required.

Our BESS team maintains current knowledge of NFPA 855 (including 2023 edition updates), NEC Article 706 across recent code editions, UL 9540 product listings for major battery vendors (Tesla, Enphase, SolarEdge, LG, Franklin, Panasonic, and others), and AHJ-specific BESS enforcement patterns across major US jurisdictions.

Our process

1. You send us project details, customer backup or peak shaving requirements, preferred battery vendor (or request recommendation), and site conditions
2. Our engineer verifies UL 9540 listing for specified equipment and any UL 9540A large-scale fire test data required
3. Battery sizing calculated against customer requirements (backup duration, peak shaving kW, TOU arbitrage strategy)
4. AC-coupled or DC-coupled architecture selected based on new-build vs retrofit and customer requirements
5. Electrical design drafted per NEC Article 706 with all required disconnects, overcurrent protection, and grounding
6. NFPA 855 fire code compliance documented including setbacks, ventilation, detection, and signage
7. Structural mounting design for wall-mount, floor-mount, or outdoor enclosure installation
8. Rapid shutdown coordinated with solar PV system per NEC 690.12
9. Complete plan set delivered including electrical, structural, and fire code sections

Tools and standards

Our BESS team works in AutoCAD, AutoCAD Electrical, Revit for structural mounting details, and manufacturer-specific design tools (Tesla Powerwall Design Tool, Enphase Enlighten, SolarEdge Designer, and others). We stay current on UL 9540 listings, NFPA 855 code updates, and AHJ-specific BESS enforcement patterns.

Client-preferred tools: Our team can be trained to use the tool preferred by the client. If your workflow depends on a specific platform, template, or drafting standard, we adapt to it rather than force you into ours.