Vertical Modularity of 25/30 kWh — Application Note
lunarenergy.com
This Application Note outlines the certifications and capabilities of the Lunar System for vertically installing 25 or 30 kWh of battery energy, and provides guidance on SolarAPP permit applications.
Battery Energy Configurations
Aggregate Energy | Configuration | Model Number(s) |
5 kWh | (1) 5 kWh DC ESS | LE-DC-UNIT |
10 kWh | (1) 10 kWh AC ESS | L2-ESS-10KWH |
15 kWh | (1) 15 kWh AC ESS | L2-ESS-15KWH |
20 kWh | (1) 20 kWh AC ESS | L2-ESS-20KWH |
25 kWh | (1) 20 kWh AC ESS + (1) 5 kWh DC ESS | L2-ESS-20KWH + LE-DC-UNIT |
30 kWh | (1) 20 kWh AC ESS + (2) 5 kWh DC ESS | L2-ESS-20KWH + (2) LE-DC-UNIT |
UL 9540 Certification
Lunar's 5 kWh DC ESS (LE-DC-UNIT) is certified to UL 9540 as a Certified DC ESS (Energy Storage System Subassembly). It contains all necessary Modules, Power Conversion, and Battery Management Systems to be considered a stand-alone DC Battery Energy Storage System.
The Lunar AC ESS is defined by UL 9540 as a Multi-Part ESS. The 10, 15, and 20 kWh configurations are Certified to UL 9540 as multi-part AC ESS. One or two additional DC ESS units can be vertically installed to the Multi-Part AC ESS for energy expansion.
Each individual wall bracket secures the 5 kWh battery to the wall and is self-supported independently of adjacent battery units.
UL 9540A Test Report
Testing has been completed for the individual DC ESS and the full multi-part AC ESS with two optional DC ESS expansions per ANSI/CAN/UL 9540A:2025 5th Edition (March 12, 2025).
Spacing: Fixed by mechanical interface of wall brackets — no additional spacing or protective devices required between vertically installed DC ESS units.
This compliance documentation satisfies the 2021/2024 International Residential Code (IRC) definition for a "unit" from R328.5. The aggregate energy of the vertically installed system must meet the aggregate energy requirements of R328.5 sections 1-4, while meeting the spacing requirements of R328.3.1.
SolarAPP Permit Applications for Systems >20 kWh
To configure systems with aggregate energy exceeding 20 kWh in SolarAPP:
Inverter Selection: Choose the "10-005025" inverter model.
ESS Model: Specify "L2-ESS-20KWH" as the Energy Storage System Model.
DC Expansion: Select "LE-DC-UNIT" from the dropdown menu for DC expansion models.
Source document: https://documents.lunarenergy.com/vertical-modularity-of-30kwh25