In one line
Annual energy produced per kilowatt-peak of installed capacity — the number that lets a 5 kW rooftop and a 500 MW plant be compared on the same axis.
What it means
Specific yield divides annual generation by installed DC capacity, producing a figure that captures both resource quality and system efficiency. Typical values run from roughly 900–1,100 kWh/kWp in northern Europe to 1,400–1,700 in most of India and 1,800–2,000+ in the sunniest tracked installations of Rajasthan, Chile or the Gulf. Because it embeds the local resource, specific yield is the right metric for comparing investment options across sites and the wrong metric for judging whether a given plant is healthy — for that, performance ratio removes the weather. In practice analysts use both: specific yield to size revenue, performance ratio to diagnose operations.
Worth knowing
- Embeds both resource and system quality in one number.
- Right for comparing sites; wrong for diagnosing a single plant's health.
- Trackers add roughly 15–25% over fixed-tilt at the same site.
- Directly proportional to revenue at a fixed tariff.
Field notes
- 1Always state whether the figure is DC-based (kWh/kWp) or AC-based (kWh/kWac) — the two differ by the DC/AC ratio and are frequently confused in comparisons.
- 2Use P50 for base-case revenue and P90 for debt sizing; a single-point yield figure hides the distribution lenders care about.
Common mistakes
- Comparing a tracked plant's yield to a fixed-tilt plant's and concluding the modules are better.
- Mixing DC- and AC-denominated yields in the same comparison table.
Frequently asked
What is a good specific yield for solar?
It depends entirely on location: roughly 900–1,100 kWh/kWp in northern Europe, 1,400–1,700 across most of India, and 1,800–2,100 at the sunniest tracked sites. Compare only against other plants in a similar resource zone.
How is specific yield calculated?
Divide the annual energy delivered in kWh by the installed DC capacity in kWp. Always note whether the denominator is DC (kWp) or AC (kWac), because the two give materially different numbers.
Sources
- [1]PV system yield benchmarking — NREL
- [2]Global solar resource and yield data — World Bank Global Solar Atlas
Related terms
Browse every term in the renewable energy glossary, or read the latest analysis on Solar PV.