California EV Charging Permitting: A Guide for Multifamily & Commercial
California EV Charging Permitting - Engineering & Design Workflow
THE ENGINEERING PROCESS:
1. FACILITY ASSESSMENT
New Construction:
CALGreen 2025 mandatory (effective January 1, 2026)
Multifamily: 100% EV-ready per unit (assigned + unassigned) PLUS 25% installed EVCS
Hotels: 65% total (40% receptacles + 25% EVSE)
Office: Up to 75% of employee parking
4:1 sharing allowed with ALMS (3.3kW minimum per port)
Existing Facility:
CALGreen triggered only if adding more than 10% parking
Start with capacity study
2. CAPACITY STUDY
Gather:
Service size (main breaker rating)
Voltage and phase
12 months utility bills (peak kW demand)
Panel schedules
Calculate Available Capacity:
Available Capacity = (Service Rating × Voltage × 1.732 × 0.8) - Peak Load
Example: 400A, 208V, 75kW peak
= (400 × 208 × 1.732 × 0.8) - 75kW
= 115.5kW - 75kW
= 40.5kW available for EV
3. LOAD CALCULATIONS
Step 1: Choose Sharing Ratio
1:1 (One Circuit per Port):
Total circuits = Total ports
Total load = Ports × kW per port
Use for: DCFC, critical ops, small deployments
2:1 (Two Ports per Circuit):
Total circuits = Ports ÷ 2
Total load = Circuits × kW per circuit
50% infrastructure savings
Use for: Multifamily assigned parking, workplace
4:1 (Four Ports per Circuit with EMS):
Total circuits = Ports ÷ 4
Managed load with EMS
75% infrastructure savings
CALGreen allows with 3.3kW minimum guarantee
Use for: High-density unassigned parking
Step 2: Calculate Demand
Without EMS:
Demand = (Total load from sharing ratio) × 1.25 continuous factor
With EMS (NEC 625.42(C)):
Demand = (EMS managed setpoint) × 1.25 continuous factor
Example (40 ports, 7.68kW each):
Unmanaged 1:1: 40 × 7.68kW × 1.25 = 384kW
Managed with EMS to 150kW: 150kW × 1.25 = 188kW
Savings: 196kW (51% reduction)
4. INFRASTRUCTURE DECISION
Compare EV demand to available capacity:
Sufficient Capacity:
Available capacity exceeds EV demand plus 20% margin
Tap existing service, install EV subpanel
No utility work order needed
Need Load Management:
Available capacity less than unmanaged demand
EMS reduces demand to fit existing service
Requires UL 916 listed EMS controller, CTs, network
Document in plans and Title 24 CF1R-ENV-03
Need Service Work:
Insufficient capacity even with load management
Options: Service upgrade, new meter, or new transformer
Requires utility work order
Check utility programs: SCE Charge Ready 2, PG&E EV Fleet (waitlist until June 2026), LADWP rebates
Large Scale (over 500kW):
Requires padmount transformer or medium voltage
Selective coordination study, arc flash analysis
Harmonic mitigation for multiple DCFC
5. CODE COMPLIANCE
NEC 2023 (Effective January 1, 2026):
Article 625: EV requirements
625.41: GFCI protection (4-6mA trip, UL listed)
625.42: Energy Management Systems
625.42(C): Demand reduction with listed EMS
625.44: 125% continuous load factor
625.48: Interactive systems (solar/storage)
CALGreen 2025 (New Construction):
Multifamily: 100% receptacles per unit + 25% EVCS
Hotels: 40% receptacles + 25% EVCS = 65% total
Office: Up to 75% EVCS
ALMS: 4:1 sharing with 3.3kW minimum
Title 24 Part 6 (2025):
CF1R-ENV-03 supplement if using load management
Expanded solar mandates
Photometric compliance if altering lighting
CBC Chapter 11B (Accessibility):
Table 11B-228.3.2.1 for accessible counts
Slopes: 2.08% maximum all directions
Van-accessible: 11-foot aisle minimum
Field-verify slopes before design
Accessible Requirements:
1-4 ports: 1 accessible (1 van)
5-25 ports: 2 accessible (1 van)
26-50 ports: 4 accessible (1 van)
51-75 ports: 5 accessible (2 van)
76-100 ports: 6 accessible (2 van)
101-150 ports: 7 accessible (3 van)
151-200 ports: 8 accessible (4 van)
Over 200 ports: 4% accessible
Equipment Listings:
EVSE: UL 2594 (L2), UL 2202 (DCFC)
Personnel Protection: UL 2231-1 (L2), UL 2231-2 (DCFC)
EMS: UL 916
6. ELECTRICAL DESIGN
One-Line Diagram:
Service/metering point
New panels and feeders
OCPD ratings and series ratings
Load management topology (if applicable): EMS controller, CTs, fail-safe logic
Grounding: GES, GEC, EGC
Fault duty at each bus with AIC ratings
Solar/storage notation if present
Panel Schedules:
Load summaries
Consistent circuit numbering (EV-A-1, EV-A-2, etc.)
Calculations Required:
NEC 220 demand (show sharing ratio and diversity)
Voltage drop (3% feeder, 5% total maximum)
Short-circuit at each bus
GEC and EGC sizing per Article 250
Load Management Documentation (if using EMS):
EMS controller specs (UL 916 listed)
CT locations and ratios
Setpoint logic and control cadence
Fail-safe: EVSE default to nameplate when EMS offline
Title 24 CF1R-ENV-03 supplement
7. SITE DESIGN
Accessibility (Critical):
Field-verify slopes with inclinometer BEFORE design
Relocate or regrade if over 2.08%
Van-accessible: 11-foot aisle (can share between two stalls)
Continuous accessible route from public way to EVCS
Operable parts: 15-48 inches above floor
Stall Layout:
Standard: 9 feet × 18 feet minimum
Accessible: 18 feet × 18 feet preferred
Bollards: 42-48 inches high, 36-48 inches from pedestal
Working clearance: 36 inches at equipment doors
Conduit:
Group pedestals to minimize trench
Pull spare conduits (20-30% extra)
Label spares
Signage:
"EV CHARGING ONLY" with ISA symbol (accessible stalls)
"VAN ACCESSIBLE" at van stalls
Stall ID numbers
Blue hash marks for access aisles
8. UTILITY COORDINATION (If New Service/Transformer)
Start BEFORE finalizing permit plans
Submit to Utility:
Site plan with service route and meter location
Load letter by phase (include sharing ratio)
Short-circuit data
Transformer pad/vault location
Single-line diagram
Utility Programs:
SCE Charge Ready 2:
Up to 100% make-ready rebates
TOU-EV-9 rate for load management
PG&E EV Fleet:
2+ medium/heavy-duty vehicles
CRITICAL: Waitlist until June 30, 2026 - apply immediately
5-year commitment
LADWP:
Up to $1,000 per L2 charger rebate
R-EV/A-EV rates
9. PERMIT SUBMITTAL PACKAGE
Documents:
Permit applications (building/electrical/planning)
Plan set PDF (PE stamped if required)
Load calculations and one-line (PE stamped for large projects)
Utility service letter or confirmation
Product cut sheets (UL listings highlighted)
Accessibility sheet with CBC Table 11B-228.3.2.1
Title 24 forms: CF1R, CF1R-ENV-03 (if load management)
Traffic control plan (if trenching active lots)
Plan Set Sheets:
Cover: Project data, codes, scope, utility contacts
General Notes: Demolition, trenching, backfill
Site Plan: Stall layout, accessible counts, slopes, conduit routing
Civil Details: Trench sections, paving, bollards
Electrical One-Line: Service, feeders, OCPD, EMS, grounding, fault duty
Electrical Schedules/Calcs: Panels, load calcs, voltage drop, short-circuit
Equipment Details: EVSE mounting, foundations, clearances
Accessibility Sheet: Enlarged plan, slopes, dimensions, CBC table citation
Signage/Striping: Details with dimensions
Cut Sheets: EVSE, pedestals, switchgear, CTs, EMS
Utility Package: Service letter, meter forms, transformer details
Dedicated Accessibility Sheet:
Enlarged plan (1:10 scale minimum)
Spot elevations and slope percentages
Access aisle widths dimensioned
Path of travel shown
Reach ranges verified
CBC Table 11B-228.3.2.1 citation with counts
10. PLAN CHECK REVIEW
Avoid These Common Comments:
Accessibility:
Solution: Field-verify slopes, dedicated accessibility sheet
No utility coordination:
Solution: Attach service letter or email confirmation
Load management unclear:
Solution: EMS controller, CTs, fail-safe on one-line plus narrative
AIC mismatch:
Solution: Fault calc summary, circle AIC on cut sheets
Missing signage:
Solution: Matrix with location, label text, sheet reference
Working clearance conflicts:
Solution: Dimension 36-inch clear space, door swing arcs
Inconsistent circuit IDs:
Solution: Consistent numbering (EV-A-1 format)
Missing Title 24:
Solution: CF1R and CF1R-ENV-03 if load management
QUICK DECISION FLOW:
New construction or existing?
New → CALGreen 2025 requirements apply
Existing → Capacity study first
Capacity study
Formula: (Service × Voltage × 1.732 × 0.8) - Peak Load
Choose sharing ratio
1:1 for DCFC/critical
2:1 for standard multifamily/workplace
4:1 for high-density with EMS
Calculate demand
Apply sharing ratio
Add 125% continuous factor
Reduce with EMS per NEC 625.42(C) if applicable
Compare to available capacity
Sufficient → Tap existing
Marginal → Add EMS
Insufficient → Utility work required
If utility work → Start coordination early (especially PG&E - waitlist)
Design compliance
NEC 625, CALGreen 2025, Title 24 Part 6, CBC 11B
Accessibility FIRST
Field-verify slopes before layout
Submit permit with all documentation
Respond to plan check
KEY FORMULAS
Available Capacity:
(Service Rating × Voltage × 1.732 × 0.8) - Peak Existing Load
EV Demand (Unmanaged):
(Ports ÷ Sharing Ratio) × kW per Circuit × 1.25
EV Demand (With EMS):
EMS Setpoint × 1.25
Voltage Drop (Single-Phase):
VD = 2 × K × I × L / CM
K = 12.9 (copper), I = Current (A), L = Length (ft), CM = Circular Mils
CRITICAL REMINDERS:
- Capacity study drives everything - don't skip it
- Sharing ratio determines infrastructure cost
- Field-verify accessibility slopes BEFORE design
- If using PG&E, apply to EV Fleet Program immediately (waitlist)
- Load management saves 40-60% infrastructure cost
- CALGreen 2025 allows 4:1 sharing with 3.3kW minimum
- All EV loads are continuous (125% factor per NEC 625.44)
- Accessibility sheet is mandatory and must be detailed
- Title 24 CF1R-ENV-03 required if using load management
This workflow applies to all projects: 4 ports or 200+ ports. The process is the same - only scale changes.