Cuba is suffering from a massive power grid collapse that has left 70% of the island without electricity during peak hours.Energy Minister Vicente de la O Levy reported that all national reserves of diesel and heating oil are completely exhausted.Protesters gathered in Havana to demand the restoration of power while the government struggles to manage a 2,200 megawatt deficit.The current crisis is worsening due to a restrictive fuel blockade imposed by the US that prevents necessary international imports.