Battery Storage Sizing for NJ Commercial Demand-Charge Offset

For New Jersey commercial properties with high demand charges, battery storage paired with solar can compound the economic case for solar alone. But battery sizing is project-specific — oversized batteries are wasteful, undersized batteries don’t deliver the full demand-charge offset. This post walks through how LandAir Energy sizes commercial batteries for NJ projects.

Understanding Demand Charges

NJ commercial electric bills have two main charge components:

• Energy charges ($/kWh): the total power you consumed during the billing period
• Demand charges ($/kW): based on your peak power draw during the period

On PSE&G’s GLP commercial rate schedule, demand charges typically run $18 to $25 per kW per month. For a facility with a 500 kW peak demand, that’s $9,000 to $12,500 per month — or $108,000 to $150,000 per year — in demand charges alone.

Solar alone reduces energy charges (by offsetting kWh) but doesn’t reliably reduce peak demand because solar production may not align with peak demand events. Battery storage can dispatch during peak hours to shave the peak.

Step 1: Pull 12 Months of Utility Data

Before sizing a battery, we pull your last 12 months of utility bills with interval data (15-minute or hourly readings). The interval data shows:

• When peak demand occurs (time of day, day of week, season)
• Peak demand magnitude and duration
• How many distinct peak events occur per month
• Shape of demand curve (sharp peaks vs flat plateau)

Without interval data, battery sizing is guesswork. Some NJ utilities charge a one-time fee ($50-$200) for interval data; it’s worth the cost.

Step 2: Identify the Right Peak-Shave Target

Battery sizing isn’t about eliminating peak demand — it’s about reducing peak to the point where demand-charge savings minus battery cost equals maximum NPV.

Sample analysis for a 480 kW peak demand NJ warehouse:

For this facility, all peak-shave targets produce similar payback because the cost-per-kWh and demand-charge rate are linear. The right target depends on:

• Available battery footprint (space constraint)
• Facility appetite for upfront capital
• Whether the battery serves backup power role (sizing then includes critical loads, not just demand shaving)

Step 3: Confirm NJESI Eligibility and Capture

The NJ Energy Storage Incentive (NJESI) program provides upfront capacity-based incentive for paired solar + storage systems. Typical incentive: $400 to $700 per kWh of battery capacity.

For a 200 kWh battery, that’s $80,000 to $140,000 in upfront NJESI incentive — substantially reducing net battery cost. NJESI program has annual capacity caps; timing matters.

Step 4: Choose Chemistry — LFP vs NMC

For NJ commercial battery storage in 2026, two chemistries dominate:

• Lithium-Iron-Phosphate (LFP): Safer chemistry, much lower fire risk, longer cycle life (6,000-10,000 cycles), lower energy density. Most common choice for NJ commercial in 2026.
• Nickel-Manganese-Cobalt (NMC): Higher energy density (smaller footprint), shorter cycle life (3,000-5,000 cycles), greater fire risk requiring more extensive suppression. Used when space is critically constrained.

For most NJ commercial installations, LFP is the right choice. We recommend NMC only when space constraints justify the trade-offs.

Step 5: Model Federal ITC and Bonus Depreciation

The 30% federal ITC applies to batteries paired with solar AND charged at least 75% from solar (the paired-storage rule). Standalone storage also became ITC-eligible under the IRA, but qualification rules differ.

For paired solar + storage commercial projects in NJ:

• Federal ITC (30%) applies to both solar and battery
• MACRS depreciation applies to combined system
• NJESI capacity incentive applies to battery only
• NJ SuSI credits apply to solar production only

The combined stack typically produces simple payback of 4 to 6 years for solar + storage on NJ commercial properties with strong demand-charge profiles.

For NJ commercial property owners considering battery storage, the math is specific to your bill and load shape. Our Commercial Energy Storage service models battery sizing against your actual utility data before recommending any specific configuration.