Generators: Sizing Guides, Comparisons & Top Brands at PES Supply
Choosing a generator is a load calculation, not a guess. This hub organizes everything Portlandia Electric Supply has published on standby and portable generators in one place: the sizing guides that walk through running watts, starting surge, and NEC transfer-switch rules; the head-to-head brand comparisons contractors actually ask for; deep-dive brand guides on Generac, Kohler, Cummins, Briggs & Stratton, and Champion; and the collections where you can price the equipment itself. Whether you are speccing a 22 kW air-cooled Guardian for a 200A home or a 60 kW liquid-cooled unit for a small commercial panel, start with the sizing guide below, compare the brands head-to-head, then run your load list through the free sizing calculator before you request a quote. Every article here is written from the wholesale side of the counter — real install questions, real warranty fine print, and the spec-sheet details that decide which unit lands on the pad.
Start here
Whole Home Generator Sizing Guide 2026: How Many kW Do You Actually Need? →
The definitive PES sizing walkthrough — a 14-item load checklist, central AC starting-surge math, and the 14/18/22/26 kW decision tree we use on real quotes. Read this first; every other guide on this page assumes it.
Sizing Guides & Load Math
kW-class deep dives — what each generator size actually carries, with appliance and HVAC load tables, fuel consumption, and transfer-switch notes.
- The Complete Guide to 26kW Generators — The largest air-cooled class — whole-home coverage for big loads, dual AC, and the dimensions question every buyer asks.
- 22kW Generators: What You Need to Know — The best-selling residential class — whether 22 kW is big enough for your home, answered with load math.
- The Power of 10kW Generators — Entry standby and large portable territory — what a 10 kW unit will and will not start.
- Best Power Backup: 60kW Generators — Liquid-cooled commercial class — small business, agricultural, and multi-panel applications.
- kVA to kW Conversion Guide for Installers — Nameplate kVA vs real kW — power factor math for commercial generator and UPS spec sheets.
Head-to-Head Comparisons
Contractor-grade shootouts on NG output, monitoring, enclosures, warranty tiers, and the service-network factor that actually decides brand.
- Generac vs Kohler Home Standby: 22–26kW Compared — Guardian vs RCL — the two dominant air-cooled brands on output, monitoring, enclosures, and dealer coverage.
- Generac vs Cummins Commercial: Liquid-Cooled 36–60kW — Protector vs Quiet Connect — liquid-cooled commercial units compared on engine, alternator, and service.
- Generac Warranty Explained: 5, 7 & 10-Year Coverage — What the extended warranty tiers actually cover — parts, labor, and travel by year, and whether it is worth it.
Brand Guides
Dealer-level specs, product-line maps, and buying guidance for every major generator brand we stock — written for contractors and installers.
- Generac Power Systems Brand Guide — Guardian, Protector, and portable lines — the market leader's full residential and commercial range.
- Kohler Energy (REHLKO) Brand Guide — Premium standby units with commercial-grade engines — the RCL and liquid-cooled lineup.
- Cummins Brand Guide — Quiet Connect and commercial gensets — the engine maker's residential-through-industrial range.
- Briggs & Stratton Brand Guide — Value-priced standby power — Fortress and PowerProtect lines through 100 kW.
- Champion Power Equipment Brand Guide — Value-driven portables and home standby — dual-fuel flexibility at aggressive price points.
Tools
Free calculator — check your load math before you buy.
- Generator Sizing Calculator — What Size Standby? — 14-item load checklist with running and starting watts, AC tonnage surge, and a kW-class recommendation.
Shop Generators
In-stock standby and portable units, transfer switches, and accessories — wholesale pricing with freight arranged nationwide.
- All Generators — The full catalog — portable through commercial standby.
- Generac — Guardian air-cooled and Protector liquid-cooled units.
- Kohler — RCL residential and commercial standby units.
- Cummins Generators — Quiet Connect residential and RS-series commercial.
- Briggs & Stratton — Standby units through 100 kW at value pricing.
- 22kW Generators — The most-quoted residential size class.
- 26kW Generators — Maximum air-cooled output for large homes.
- 60kW Generators — Liquid-cooled commercial backup.
- Commercial Standby — Three-phase and large single-phase units.
- Portable Generators — Jobsite, RV, and emergency portable power.
Why contractors source from PES Supply. We are a wholesale supplier, not a content farm — every guide on this page exists because we sell and support the equipment it covers. That means real model numbers, real warranty terms, and honest limitations instead of affiliate-listicle rankings. Order through any collection link and you get contractor pricing, consolidated freight on multi-pallet orders, and a support line staffed by people who can read a spec sheet.
Get a wholesale quote. Sizing a standby generator for a home, shop, or commercial panel? Send us your load list and we'll spec the unit, transfer switch, and fuel configuration — wholesale pricing, freight arranged. Request a quote →
Portlandia Electric Supply stocks generators, solar, battery storage, EV charging, and electrical supplies at wholesale — browse all collections or explore our other hubs: Generators · Solar · Battery Storage · EV Charging · Electrical.