I coordinate emergency power for a living. That means when a generator dies at 9 p.m. the night before a deadline, I'm the one getting the phone calls. In the last eight years, I've handled more than 200 rush orders, including same-day turnarounds for commercial clients. Along the way, I stopped comparing sticker prices and started comparing total cost of ownership.
This article compares the Briggs & Stratton generator 5500 (the portable workhorse) against a 13kw Briggs and Stratton generator (the standby option), and it covers the difference between inverter generator and regular generator models. I'll also talk about two parts that don't get enough attention: the pleated air filter and the electric fuel pump for diesel. This is accurate as of January 2025. Models, prices, and emissions rules change fast, so verify current specs and local codes before buying.
What We're Actually Comparing
The real question isn't 'Which B&S generator is better?' It's 'Which one costs less over the next five years?' The 5500 portable has a lower price, but it comes with labor, fueling, and extension cords. The 13kW standby costs more upfront, but it can be wired into a transfer switch and serve a building automatically.
Look, I'm not saying the portable is always wrong. I'm saying I've seen buyers choose the portable to save money, then spend more on overtime labor in one long outage than the standby cost difference. On the flip side, I've seen a standby unit sit for years without ever starting. There's no universal winner.
Dimension 1: 5500 Portable vs 13kW Standby - Cost Over Time
Start with the obvious. The Briggs & Stratton generator 5500 is a portable unit. Typical running output is around 5,500W with a surge higher than that, depending on model. You wheel it out, connect cords, and fuel it. It works. The 13kw Briggs and Stratton generator is a different animal: a permanent installation with a transfer switch, fuel line, and often an automatic start controller.
Here's the thing about price: 2025 list-price bands that are publicly available put the 5500 roughly between $800 and $1,300. A 13kW standby unit typically lists in the $4,000 to $6,500 range, before install. And install isn't optional for a standby—it's the price of admission. Transfer switch, concrete pad, permits, and labor can easily add $1,500 to $3,500 depending on the site. Verify those numbers at the current B&S dealer price list; they move.
But the bigger cost difference is labor. During an outage, someone has to take the portable outside, connect it, fuel it, check it, and shut it down. That someone has an hourly rate. I've calculated this for more than 200 emergency jobs: after eight hours of manual running, the 'low-cost' portable can be more expensive than an automatic standby unit. Not because fuel is expensive—because time is.
Dimension 2: Pleated Air Filter and Electric Fuel Pump for Diesel
The two cheapest parts on a generator can shut it down faster than any engine issue. Let's start with the pleated air filter. Most current B&S portables use a pleated element instead of an old-style foam filter. The pleats give it more surface area, so it traps more dirt before clogging. But unlike foam, you can't wash it. You replace it. A plugged pleated air filter makes the engine run rich, fouls the spark plug, and increases fuel consumption. In 2022, a 5500 failed a load test because its pleated air filter looked fine on the outside but was packed on the inside. A $20 filter fixed it. Better than replacing a carburetor.
Now the electric fuel pump for diesel. On larger diesel B&S units, the pump pulls fuel from the tank to the injection system. It's an electric part, and it will eventually fail. But here's something installers won't tell you: most 'fuel pump' failures I see are actually filter failures first. A dirty tank, water, or algae plugs the fuel filter, and then the pump cavitates. Someone swaps the pump, and the problem comes back. A spare diesel fuel filter costs a fraction of a pump replacement—especially if you need one after hours.
What's the comparison? A cheap filter is not an optional accessory. It's total cost of ownership. A pre-scheduled air filter change and fuel filter change costs less than one emergency service call. (And honestly, it's one of the few maintenance tasks you can actually plan.)
Dimension 3: Difference Between Inverter Generator and Regular Generator
People ask me about the difference between inverter generator and regular generator all the time. Here's the short version. A regular generator runs at a fixed engine speed to produce 60 Hz power. An inverter generator runs at variable speed and then electronically conditions the output. Inverter models are generally quieter, lighter at the same output, and safer for sensitive electronics. Regular models are often cheaper, simpler, and available in larger sizes.
In the B&S lineup, the 5500 portable is a regular generator. That's not a flaw—it's the right trade for heavy loads. If you're running power tools, commercial kitchen equipment, or motor loads, a regular generator gives you more surge and straightforward service. If you're powering a server rack or medical devices, you want an inverter model (or a UPS) because output from a regular generator can include voltage swings you don't want. The difference matters when your loads are sensitive.
Surprise, surprise: for many commercial tasks, the regular generator is the better purchase. Inverter units cost more upfront, and if you're usually running at high sustained load, the fuel advantage disappears. But if you're running light loads for hours, an inverter's variable speed can cut fuel use and noise enough to make sense.
Choice Recommendations
Stop looking for a single 'best' generator. Start with the scenario.
Choose a Briggs & Stratton generator 5500 if:
- You need a mobile power source for job sites or events.
- You can tolerate manual setup during outages.
- Your load is a few circuits, not an entire building.
- You budget for regular maintenance, including the pleated air filter.
Choose a 13kw Briggs and Stratton generator if:
- Power loss means lost revenue or compliance problems.
- You want automatic response without dragging gear outside.
- You have a fuel source that can support long runtime (including diesel, with the electric fuel pump maintained).
- You're prepared for installation, permits, and annual load tests.
Choose a regular generator if:
- Your loads are heavy, sustained, and not sensitive microelectronics.
- You want lower upfront cost and simple parts availability.
Choose an inverter generator if:
- You're protecting electronics or medical devices.
- Noise is a concern.
- Most of your runtime is at light load.
The Bottom Line
As of January 2025, my advice hasn't changed: compare total cost of ownership, not the tag. Include purchase price, installation, fuel system maintenance (like the electric fuel pump on diesel units), air filter changes, and the value of the hours spent getting power back. If a customer asks me which unit to buy, I ask one question: 'What is an hour of downtime worth to you?' The answer tells you everything.
Emissions compliance: before any purchase, verify the current model is legal in your state. EPA and CARB rules keep changing, so check epa.gov and carb.ca.gov for current requirements.
