Kilowatt-Peak (kWp)
Kilowatt-peak (kWp) is the rated DC output of a solar system under standard test conditions — full sunshine of 1,000 W/m² at 25 °C. A 3 kWp rooftop system in India typically generates 10–13 units of electricity per day.
kWp is the number systems are bought and subsidised by; actual output varies with location, temperature, tilt, and soiling. Roughly 80 sq.ft of shadow-free roof is needed per kWp with standard modules.
In More Depth
The word peak refers to standard test conditions (STC): 1,000 W/m² irradiance, 25 °C cell temperature and a standard spectrum. Real rooftops run much hotter than 25 °C, so summer-afternoon output is below nameplate — a module with a −0.35%/°C temperature coefficient loses about 14% of rated power at a 65 °C cell temperature. We compare real datasheet figures in our solar panel reviews.
kWp should not be confused with kW (the inverter’s AC output) or kWh (energy). A 5 kWp array on a 4 kW inverter has a DC/AC ratio of 1.25; the energy it generates, counted in kWh (units), is what your bill is credited with.
Frequently Asked Questions
- What does kWp mean in solar?
- kWp (kilowatt-peak) is the maximum DC power a solar array can produce under standard test conditions. Systems are quoted and subsidised by it — a 3 kWp system is made of modules whose rated powers add up to 3,000 watts.
- How many units does 1 kWp generate in India?
- Roughly 4 units (kWh) per day, or about 1,400–1,700 units a year, depending on location, tilt, shading and soiling. Our energy yield calculator estimates it for your city.
Part of the HUM Solar Glossary — 75+ plain-language definitions for India’s solar ecosystem, maintained as a neutral reference. Browse all terms →
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