1.8 Common misconceptions about solar systems

1.8.1 Battery life is longer than you think

Many people assume residential batteries degrade fast and only last ten years, the same way EV batteries do. It is not true.

Early EV batteries used NMC chemistry, which does degrade quickly. Residential storage today uses LFP, which is fundamentally more stable, cycles more times, and lasts much longer.

The battery model we use most often retains 70% of its capacity after 10,000 cycles over 15 years. A properly sized solar system cycles the battery roughly 300 times per year. After 15 years that's still under 5,000 cycles — well within spec.

You don't need to worry about battery lifespan.

1.8.2 Solar panels last a very long time

Modern panels comfortably reach 25 years.

First, panels have no moving parts — no compressor, no motor, no gears. No friction means almost no wear.

Second, a panel is a sealed semiconductor sandwich. A silicon crystal stack laminated under glass, with no water ingress and no impact damage, doesn't "break suddenly." It just degrades slowly. Today's panels routinely retain 90%+ of nameplate output even at year 25.

Third, the finance system forces panel quality up. Bank lending, insurance underwriting, and project pro formas all assume long-term stable production. A panel that can't survive 25 years can't get financed. The flow of capital forces the industry to build to that threshold.

1.8.3 Solar systems aren't fragile

A home system has three core parts: panels, inverter, battery. As long as the installation is up to code, the hardware itself is very stable.

Think about it this way: TVs and refrigerators — which run all day, every day — usually come with a 1-year warranty. Why do solar manufacturers offer 5, 10, even 25 year warranties? Because the equipment really doesn't break that often.

But the "premium" brands need to justify a premium price tag and a long-term contract. So the sales script starts with "the equipment breaks, the system fails, repairs are expensive and hard to find, you absolutely need a big-name installer," and ends with you signing up for an inflated bid and maybe an extended warranty. The entire framing exists to get you to pay more.

In reality, big-company warranty service is often *worse* than the alternatives. We'll cover this in Chapter 2.

1.8.4 Don't measure system size in "number of panels"

90% of homeowners describe their system as "I have X panels on the roof." This phrasing comes from unprofessional or deliberately misleading sales scripts. It is fundamentally wrong.

Panels vary hugely in wattage — anywhere from ~280W per panel to 500–600W per panel, more than a 2x range. Counting panels tells you nothing about system capacity.

We saw a customer who had recently installed a system using outdated 280W panels — and the salesperson kept selling them on "look how many panels you got, your system is huge."

So remember: system size is measured in kW (or kWh for battery storage), never in panel count.

1.8.5 Adding a battery is usually unnecessary

We routinely talk customers *out* of adding a battery. In California, 90% of "I want to add a battery" requests are misguided — because the actual problem isn't storage capacity.

Many California systems were installed before 2023, on NEM 1.0 or NEM 2.0. Household electricity use has crept up year over year, eventually outpacing the system's production, and the bill starts climbing. Combined with the fact that new NEM 3.0 systems require a battery, many homeowners conclude that adding a battery to their old system will solve the problem.

It won't. Pre-2023 systems are on NEM 1.0 or NEM 2.0 with a 20-year grandfathering period — during which the grid itself acts as a free, infinite-capacity battery. There is no reason to add local storage.

These customers don't have a storage problem. They have a *production* problem — they need more energy, not more storage. The real solution is to expand the array with additional panels, not bolt on a battery.

System expansion has its own design considerations. Reach out and we'll walk you through them.