The capture price is the volume-weighted average day-ahead price a technology actually earns — hours with more generation weigh more. The capture rate divides that by the unweighted baseload price: below 100% means cannibalisation, the asset producing most when prices are lowest. This page tracks monthly solar and wind onshore capture prices and capture rates for the Poland bidding zone (PL), computed from ENTSO-E hourly day-ahead prices and per-technology generation, from 2015.
Solar and wind onshore in the PL bidding zone, most recent month with data. Months are bucketed in market time (Europe/Berlin).
The capture price weights every hour's day-ahead clearing price by that hour's generation of the technology: capture = Σ(price × generation) / Σ(generation). The baseload price is the plain monthly mean of all hourly prices — what a flat, always-on asset would earn. The capture rate is capture ÷ baseload; the industry also calls it quality factor, value factor, or Marktwertfaktor. Negative prices are included as-is, and hours with zero generation contribute zero weight.
Falling solar capture rates are cannibalisation in action: every new panel produces in the same midday hours, pushing exactly those clearing prices down.
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