BESS Procurement Checklist for Commercial Sites

1. Collect 12 months of interval data

Ask your utility for 15-minute interval data for at least a full year. Peak shaving savings depend on how tall and how long your peaks are, and monthly bills alone hide that. Use the data to set a realistic kW reduction target and duration, then run a first screen with our battery storage calculator.

2. Write a performance specification, not a product name

• Power (kW) and usable energy (kWh) at the point of interconnection, not just nameplate.
• Required use cases: peak shaving, backup, tariff arbitrage, demand response.
• Round-trip efficiency measured AC-to-AC, including auxiliary loads such as HVAC.
• Chemistry preference (LFP is the common choice for stationary commercial systems).

3. Compare warranties on the same basis

Ask every bidder for guaranteed usable capacity by year, the throughput or cycle limit, availability guarantees and what happens when capacity falls below the guarantee (augmentation, liquidated damages or replacement).

4. Confirm safety certifications

In North America, ask for UL 9540 system listing and UL 9540A large-scale fire test results, and confirm the design meets NFPA 855 and your local fire code. Involve the fire marshal early; late design changes are expensive.

5. Plan interconnection and permitting

Behind-the-meter systems still need a utility interconnection agreement. Ask who files it, what studies may be needed and how long the utility typically takes.

6. Contract terms that matter

• Fixed price vs. pass-through for tariffs and equipment cost changes.
• Commissioning tests that must pass before final payment.
• Software and controls ownership, data access and monitoring fees.
• Operations and maintenance scope, response times and end-of-life recycling.