Granted, this is about running out of energy that they are allowed to use, not running out of energy completely. Apparently the starting battery capacity is 52kWh, but for every minute spent behind safety car, the amount of energy each driver may use is reduced by 1kWh - and there were 5 safety car phases in the race, meaning that 19kWh were cut from the allowed amount of energy for each car. So definitely a miscalculation by the race control, but either way, they just keep on making a mockery out of themselves.. A complete farce. They even put a chicane in the middle of the straight to give the cars an additional heavy braking zone as a recharge opportunity.