Your inverter should generally match or slightly exceed the DC capacity of your solar panel array — for example, a 5kW panel array typically pairs with a 5kW-class inverter. The exact size also depends on your average monthly electricity consumption and any future load you plan to add, such as air conditioning or an electric vehicle charger.
Matching Inverter to Panel Capacity
Inverters are usually rated close to the panel array's total wattage, sometimes slightly undersized (a common practice called DC/AC oversizing) since panels rarely hit their peak rating simultaneously. A qualified installer calculates this ratio during system design rather than guessing.
Sizing by Monthly Electricity Usage
- 3kW systems — suited to smaller homes with modest monthly units, typically priced PKR 600,000-900,000 installed.
- 5kW systems — the most common residential size, generating roughly 550-750 units/month, priced PKR 800,000-1,200,000 installed.
- 10kW systems — for larger homes or higher consumption, priced PKR 1,500,000-2,200,000 installed.
For a detailed cost breakdown, see our guide on 5kW solar system cost in Islamabad.
Risks of Getting the Size Wrong
An undersized inverter can clip peak generation and lose you output on sunny days, while an oversized inverter adds unnecessary cost without proportional benefit. Both scenarios reduce the return on your investment, which is why accurate sizing matters more than simply choosing the largest available unit.
How Tripower Determines the Right Size
Every project starts with a free site survey and bill-based load analysis, followed by a custom system design that specifies the exact panel and inverter capacity for your roof and consumption pattern. Learn more about our solar installation process or request a free survey to get started.
Frequently Asked Questions
Can one inverter serve panels rated higher than its capacity?
Yes, to a degree — moderate oversizing of the panel array relative to the inverter is common practice and can improve output during low-light conditions, but excessive oversizing wastes potential generation.
Does inverter size affect net metering approval?
Yes, IESCO net metering approval is based on your system's rated capacity, so accurate sizing during design ensures your paperwork matches the installed equipment.
Should I size for future expansion?
If you plan to add panels or appliances later, it's worth discussing a slightly larger inverter or a hybrid model during your site survey so the system can accommodate growth without a full replacement.