Existing Building per Utility Data

Evaluate existing electrical demand using historical utility interval data and proposed new loads.

Existing Building Load Evaluation — NEC 220.87

NEC 220.87 allows existing building loads to be evaluated using recorded maximum demand from utility data.

125% of Existing Maximum Demand + New Load = Total Calculated Load

This method helps determine whether the existing electrical service has capacity for EV chargers, heat pumps, water heaters, and other new loads.

Note: Subject to applicable NEC and AHJ requirements.

Project & Utility Info
Utility Data
Load Analysis
Add New Loads
Results

Project & Utility Information

Used to suggest the electric utility.

Existing Electrical Service

Example: 100, 150, 200, 400

Utility Interval Data

Upload utility interval data

CSV format. The highest numeric value found in the file is used as the maximum demand (kW).

— OR —
Enter the maximum recorded kW from the utility data.

Load Analysis

Existing Demand

Equivalent Demand0.00 kVA
125% Existing Demand0.00 kVA

Electrical Service

Service Rating—
Service Capacity0.00 kVA

Available Electrical Service

Capacity Remaining0.00 kVA

New Electrical Loads

Add proposed loads that must be included with the existing demand analysis.
Load NameLoad TypeQtyAmpskWVoltage

Load Analysis Results

Evaluation Result: PASS

Existing Demand

Equivalent Demand
125% Existing Demand

Electrical Service

Service Rating
Service Capacity

New Electrical Loads

Total Added Load
Number of Loads

New Electrical Loads Included in Analysis

#Equipment NameLoad TypeQtykVA (each)Total kVAVoltage
125% Existing Demand
+
Total New Electrical Loads
=
Total Calculated Load

Load Calculation Summary (NEC 220.87 Method)

DescriptionkVAAmps @ 240V
Note: This analysis applies NEC 220.87 using the utility data and project information provided. Final design and approval remain subject to the Authority Having Jurisdiction.