The Carlin Motorsport driver set a time of 1:49.957 on his final lap, after the chequered flag had been shown, despite touching the wall at one point and bending a wishbone on the car.
Milos Pavlovic (GD Racing) headed the first qualifying group with a 1:50.410 lap. His time, also set after the flag had been shown, denied late pace-setters Markus Winkelhock (Draco) and Robert Kubica (Team Epsilon), who finished within two tenths of a second of Pavlovic.
Unlike first qualifying, the average of the five fastest times from each group in the second qualifying was within the 0.3% mark. This means both groups will be merged for race two and the times will run concurrently.
Power is therefore followed by Pavlovic and Winkelhock. Fourth is Alx Danielsson, whose 1:50.530 lap in the slower second half of qualifying put him second only to Power. Kubica starts fifth, ahead of Colin Fleming (Jenzer Motorsport).
Power, last on pole at Zolder, said: "I haven't been to any of the tracks on the calendar, but this is one that no-one else has been to either, so that helps me for the championship. It is important for me to finish strongly in both races."
Power's teammate Andreas Zuber's fraught Bilbao meeting continued when he was adjudged by the stewards to have received outside assistance when he stopped on the track early in the session with a fuel pump problem. Zuber got going again and set the third quickest time before being black-flagged. He will not start either race after crashing in qualifying one.
During the session, the black flag was mistakenly shown to Eric Salignon's Cram Competition car. His fourth-fastest time became third when Zuber was excluded, meaning he starts eighth on the grid, behind Tristan Gommendy (KTR).
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