The inverter is the one component you will interact with every day, and sizing it wrong quietly costs generation for years. Here is how professionals choose the capacity.
Match it to your panels
A common rule: inverter capacity ≈ 80–110% of total panel capacity. Panels rarely hit rated output in real conditions (heat, dust, angle), so a slightly smaller inverter runs at its efficient peak for more hours — this is normal and called DC oversizing of panels.
Match it to your load and phase
- Up to ~5kW single phase: homes, small shops
- 5–10kW and above: three phase, larger homes, offices, small factories
- Check your sanctioned load and discom approval limits
- For heavy motor loads (pumps, compressors), check starting-surge capacity
On-grid, hybrid or off-grid?
- On-grid: cheapest, no backup during cuts
- Hybrid: adds battery backup; costs more, needs battery budget
- Off-grid: for locations with unreliable grid; sized on battery autonomy, not just panels
Signs your inverter is wrongly sized
- Constant clipping — panels produce more than the inverter can convert
- Frequent overload trips when loads start
- Inverter running at max capacity for long hours (heat and wear)
- Planned expansion with no headroom left
Frequently asked questions
Can I use a bigger inverter than my panels?
Yes, but an oversized inverter operates at low efficiency percentages and may struggle to start MPPT in low light. Matched sizing performs best.
Can I add panels later to the same inverter?
Up to the inverter's max DC input. Tell your installer your expansion plans before choosing capacity.
Need a solar inverter repaired?
Share your inverter brand, model and error code — our technicians will guide you and share an estimate before any repair starts.