Solar saturation: the number every door-to-door rep should know before knocking

Ask ten solar reps how they pick a neighborhood and you'll hear ten versions of the same answer: gut feel. A manager worked it years ago, the freeway exit is convenient, the houses look nice. Then they spend a Saturday learning what the county already knew: a third of those doors were never going to buy.

There's a number that predicts a huge share of that wasted effort, and it's computable from public records: block-level solar saturation — the percentage of roofs on a given block that already have solar permits on file.

Why saturation cuts both ways

High saturation (say, 30%+) means the block has been harvested. The early adopters bought, the neighbors who were persuadable got persuaded during the boom years, and everyone left has said no to a dozen reps. Your close rate there isn't just lower — the conversations are worse, because you're pitch number thirteen.

But zero saturation isn't the target either. A block where nobody has panels — in a metro where solar is everywhere — is often telling you something: renters, shade, HOA friction, or demographics that don't pencil. The sweet spot is the low-saturation block adjacent to high-saturation blocks. Demand is proven two streets over; these doors just haven't been worked.

How to compute it (or have it computed)

The raw materials are public. County assessor rolls tell you which parcels are single-family homes and whether the owner lives there (in California, the homeowner's exemption is a strong owner-occupancy signal). City building-permit datasets tell you which addresses pulled solar PV permits and when. Join the two, grid the map into small cells, and divide.

Doing this by hand for one neighborhood is a weekend of spreadsheet work. Doing it for a whole county is a data pipeline — which is exactly what KnockGenius runs monthly, so reps get the answer as a ranked knock-list instead of a CSV project.

Using it in the field

Treat saturation as your routing layer, not your pitch. Walk the low-saturation pockets, and when a homeowner says 'nobody around here has solar,' you have a real answer: the Hendersons two blocks east went solar in 2023, and here's what changed on their bill structure since.

Combine it with owner-occupancy filtering and utility-zone awareness (an SCE household's bill pain is not an LADWP household's bill pain) and you've eliminated the three biggest sources of wasted knocks before you park the car.