"We are having to identify which projects are [financially] worthwhile," says Entrecanales.

He says Acciona was recently offered a 20-year power-purchase agreement (PPA) from a utility at $39 per MWh. "From a returns point of view it doesn't make any sense whatsoever," he says.

Acciona has a five-year plan until the end of 2014 to install 600-700MW of power capacity every year.