Generation · Solar
A panel on a balcony charges a phone. An array sized for a property runs a well pump in February, on the shortest day of the year, after four days without sun. Those are different problems, and they are solved with different arithmetic.
The boundary
Portable panels, a first rooftop system, running a few circuits through an outage. Those pages answer the questions a household asks, and most readers never need anything past them.
This section answers a different question. Not how to add solar to a house, but how to size an array that carries a property through its worst month, stores what it makes, and keeps running when the weather does not cooperate.
The difference is scale and permanence, not skill. A renter with a folding panel and a homesteader with a ground-mounted array are doing the same physics at different sizes.
What changes
A household system that falls short in December is an inconvenience. A property system that falls short in December is a well that does not pump. Four things change when the array has to carry everything.
An annual average hides the month that actually breaks the system. Sizing is done against the lowest sun month for the site, which is why two properties at the same latitude can need very different arrays.
Household backup thinks in hours. Property scale thinks in days without sun, which sets the size of the battery bank and, with it, most of the budget.
Inverters, controllers and monitoring draw power continuously whether anything is switched on or not. Over a full day that standing load is large enough to change the panel count.
No utility crew arrives. Panel cleaning, connection checks, battery monitoring and winter snow clearing become household work, and a system nobody can service is a system that fails quietly.
What this hub covers
Each one assumes the numbers from the one before it. The same property runs through all seven, so the figures introduced on the first page are the figures still being spent on the last.
Daily load, standing draw, and the worst-month arithmetic that decides how many panels the property actually needs.
2What days of autonomy cost in capacity, and why chemistry decides how much of a bank you can actually use.
3Where an array's output becomes usable power, and the surge rating that decides whether a well pump starts.
4Orientation, tilt, airflow and snow, and why adding panels usually beats adding moving parts.
5What the system demands electrically, why DC faults behave differently, the permit path, and where a licensed electrician stops being optional.
6Short days, low sun angles, snow cover, and the temperature limits on charging a battery bank.
7The point where roof space, shade or winter load pushes a household into property-scale planning.
Start upstream
Property scale is a step past these three, not a replacement for them. Read whichever matches where you are now.
Using portable solar during an outage, and what a small panel realistically does.
Read the guideA first portable setup, sized and wired, with honest limits on what it carries.
Read the guideWhat a homeowner should understand before signing anything, including interconnection.
Read the guideEvery page in this hub starts from one number: what the property actually uses in a day. If you have not measured that yet, the household power use guide shows how, and the power needs calculator works it out from a device list.
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