Power companies have reported generation loss of 8.7 billion units from April- February this fiscal due to coal shortages, Parliament was informed on Monday. "Power utilities have reported a generation loss of 8.7 billion units during the year 2011-12 (up to February, 2012) due to shortage of coal," minister of state for power K C Venugopal told the Rajya Sabha. These companies suffered a generation loss of 8.4 billion units in the last financial year (2010-11).