MADRID (Reuters) -Spanish grid operator Redeia will release its own report on the causes of the massive blackout that hit the Iberian peninsula on April 28, its chair, Beatriz Corredor, told a news briefing on Wednesday.

Spanish authorities say the massive power outage in April across Spain and Portugal was due to technical and planning errors that led to a cascade of failures in the grid.

Spanish grid operator Redeia blamed power plants for the massive blackout that affected the Iberian peninsula in April, as it disputed a government report that said its failure to calculate the correct energy mix was a key factor.