How we design a system
From twelve months of utility data to a modeled array and a price. What we look at, what we can tell from satellite imagery, and what has to wait for a site visit.
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Most solar quotes start with a panel count and work backward to justify it. We start with your consumption and work forward. Here is the actual sequence.
1. Twelve months of usage
This is the input everything else depends on, and it is the one thing we need from you.
Any of these work:
- A recent utility bill showing the twelve month usage graph
- A photo of that graph, taken with your phone
- A data export from your Consumers Energy or Great Lakes Energy online account
- A Green Button download, if your utility offers one
If you have only lived in the house a few months, say so. We can work from a partial baseline and extrapolate using what we know about similar homes, and we will tell you where the estimate is softer than usual.
Why it matters: your annual consumption sets both the economics and, under Michigan’s distributed generation rules, the legal ceiling on system size. A design built without it is a guess.
2. The roof, from above
Before anyone drives out, we can determine a surprising amount from satellite and aerial imagery plus design software:
- Roof planes, their orientation, and their tilt
- Usable area after setbacks and obstructions
- Shading from your own trees, neighboring trees, and nearby structures, modeled across the whole year including the low December sun angle
- A first-pass layout and module count
What we cannot tell from above: roof condition and age, rafter spacing and structure, the electrical service and panel capacity, attic access, or what the actual condition of the shingles is. Those wait for the site visit.
3. Production modeling
We model expected annual production against local irradiance data and the specific geometry of your roof, not a national average. The output is a month-by-month production estimate, which matters in Michigan because the winter shape surprises people if they have not seen it before.
Then we run a sanity check: does the modeled specific yield look right for this latitude, this tilt, and this orientation? If a model produces a number that seems too good, it is usually the shading assumptions, and we would rather find that now.
4. Sizing to consumption
We size toward covering your usage, biased toward self-consumption, since energy you use as you generate it is worth full retail and energy you export is credited at less.
If a roof plane is marginal enough that the modules on it would not pay for themselves, we will propose leaving it off. Two extra modules that produce poorly and make the array look like an afterthought are not a favor to you.
5. Equipment selection
Module wattage, inverter architecture, racking, and attachments appropriate to your roof material and local snow load. If backup power is a priority, we need to know that at this stage rather than later, because it changes the electrical design rather than bolting on to it.
You get the equipment list by make and model. Not “tier 1 panels.”
6. Numbers you can actually check
What you get back:
- The system size and layout
- Expected annual production in kWh
- The equipment list
- The price
- How it compares against what you are paying now
If it does not make sense on your roof, that is what we tell you, and it costs you nothing to have found out.
7. Site visit, then paperwork
The site visit confirms the assumptions: roof structure and condition, electrical service, panel capacity, run distances, and where equipment will physically mount.
After that we handle permits, the interconnection application with your utility, the install, inspection, and follow-through to permission to operate.
Ready to start? Send us your usage and we will take it from there.
Want your actual numbers?
Send twelve months of usage and we will model your system and price it. No appointment required.