Solar Engineering Tools, Calculators & Checklists
Interactive, code-compliant electrical and financial tools engineered by licensed Professional Engineers (P.E.) for solar contractors, electricians, developers, and AHJ reviewers.
Solar Voltage Drop & Conductor Loss Calculator
Calculate DC string and AC 1-Phase / 3-Phase voltage drop, wire resistance, power loss in Watts, and verify NEC 3% branch circuit limits.
Commercial Solar ROI & Payback Calculator
Model commercial solar financial returns including 30%–50% Federal ITC tax credits, 5-year MACRS accelerated depreciation, and 10-year cash flow projections.
Solar String Sizing & Busbar Rule Calculator
Calculate temperature-adjusted maximum system voltage ($V_{max}$), NEC 690.8 continuous ampacity, and test panel 120% Busbar Rule compliance.
47-Point Solar Permit AHJ Inspection Checklist
The complete pre-submission checklist used by our P.E. engineers covering structural loading, NEC 690 electrical schedules, and fire roof access pathways.
All 50 States Solar Permit Requirements Guide
Filterable state-by-state reference directory detailing P.E. stamp mandates, adopted NEC code editions (2017/2020/2023), and utility interconnection rules.
NEC 690 Conductor Sizing Reference Tables
Complete base ampacity charts for copper/aluminum THWN-2 and PV Wire, rooftop ambient temperature deratings, and conduit fill reduction factors.
Roof Type vs. Solar Mounting Compatibility Guide
Interactive tool matching composition shingle, tile, standing seam metal, and flat membrane roofs to certified racking hardware and attachment methods.
Solar Engineering Glossary & Code Encyclopedia
Searchable reference dictionary explaining technical solar terminology, NEC code articles, IEEE standards, and structural equations in clear language.
Need Your Calculations P.E. Stamped for Permitting?
Our licensed Professional Engineers deliver jurisdiction-ready residential and commercial solar permit plan sets in 24 to 48 hours nationwide.