VanBuildCalculator.online ABYC E-11 Compliant

Off-Grid Solar & Battery Capacity Sizer

Nominal circuit standard
80% Max DOD
2.0 days
1.0d (Light) 2.0d (Standard) 5.0d (Storm)
4.0 hrs
Winter (2.5h) Avg US (4.0h) Summer (6.0h)
Appliance Loads

Daily Electrical Consumers

5 Active
ABYC E-11 Safety Engine

Conductor Wire Gauge (AWG) & Fuse Sizer

3% Max Drop
Inverter, charger, or branch feed
Distance from battery to load
Recommended Conductor
6 AWG Marine Tinned Copper
Drop: 2.1% (0.25V @ 12V)
Recommended Fuse / Breaker
50A MRBF / MIDI
125% continuous circuit protection
Electrical Sizing Telemetry
ABYC E-11 • NEC 551
Required Battery Bank Capacity
128 Ah
1,638 Wh usable storage @ 80% DOD
Solar PV Array
340 Watts
Approx. 2x 185W Panels
MPPT Charge Controller
30 Amps
Includes 25% safety headroom
Daily Load (Total)
765 Wh/day
59.8 Ah/day @ 12.8V
Inverter Standby Overhead
+480 Wh
20W Inverter Standby Active
✓
ABYC Certified Engineering Sizing Reserve

Sufficient energy budget for continuous Starlink, refrigeration, and ventilation across 2.0 days of storm cover.

Live Math Transparency & Engineering Formulas
Total Daily Energy Consumption: Daily Wh = ∑(DC Watts × Hours) + ∑(AC Watts × Hours × 1.15) + Inverter Idle (480 Wh)
Usable Storage Capacity (Ah): Required Usable Ah = (Total Daily Wh × Days of Autonomy) / (Nominal Voltage × Max DOD)
Solar PV Array Generation (Watts): Required Solar W = Total Daily Wh / (Peak Sun Hours × 0.75 Derating Factor)
ABYC Conductor Circular Mil Area: CM = (10.75 × Current Amps × 2 × Distance Ft) / (System Voltage × 0.03 Max Drop)
MV
Reviewed by Marcus Vance ABYC Certified Master Marine/Mobile Electrical Technician & Mechanical Engineer Calibrated against ABYC E-11 (AC & DC Systems on Boats/Vehicles) and NEC Article 551 (Recreational Vehicles).