Luminous discharge solar cell can show (3)

I believe the answer is:

arc

'luminous discharge' is the definition.
(I've seen this before)

'solar cell can show' is the wordplay.
'show' indicates the answer is hidden within the clue.
'ARC' is hidden within 'solar cell can'.

(Other definitions for arc that I've seen before include "bends?" , "Section of circumference" , "Bow" , "Segment of circle" , "section of Circle Line" .)

I've seen this clue in The Times.

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