Compare capacity, not marketing labels
| Panel DC rating | What to compare | Important limitation |
|---|---|---|
| 400 W | Space, mounting and inverter rating | Actual production varies with orientation, shade and weather. |
| 800 W | Total DC rating, inverter AC output and storage compatibility | Panel capacity is not the same as continuous AC output. |
| 1,200 W | Circuit rules, allowed system limits and mounting load | A kit size is not permission to connect in your location. |
Rated watts are not daily watt-hours
A rating describes power under specified conditions. Daily energy depends on sunlight, temperature, orientation, shade and conversion losses. For illustration, an 800 W array with 4.5 peak sun hours and an 85% performance factor produces approximately 3.06 kWh per day before considering how much your household can use or export.
Use the complete purchase price
Include panels, inverter, approved mounting, delivery, battery if selected, electrical work and any required fees. Product prices and weights differ across models, so this guide does not present unsourced generic weights or current market prices. Compare actual datasheets and written quotes.
Check storage compatibility
Confirm supported battery models, usable Wh, charge/discharge power, expected cycling and warranty conditions. Do not assume an inverter can accept an arbitrary battery or provide outage backup. Verify how the system measures household demand and limits export if your tariff or local rules require it.
Read the service terms
- Who handles repairs and where must the equipment be shipped?
- Are shipping, removal and reinstallation included?
- Is the warranty transferable when you move?
- Are output claims based on DC nameplate power or expected AC generation?
- Is the full configuration approved for the intended connection?
Choose for your load and space
A larger kit may produce more unused or poorly compensated exports. Compare expected daytime household demand, available placement and utility rules before scaling up. A smaller, well-positioned array can be a better fit than a larger shaded one.
Finish the readiness checklist, then compare costs and tariffs in the calculator. We do not rank specific products or claim hands-on tests that we have not performed.