Exhibit 11 Trigen Energy Corporation and Subsidiaries Computation of Earnings Per Share (In thousands, except per share data) Year ended December 31, ---------------------------------------------------------------------------- 1999 1998 1997 1996 1995 ------- ------- ------- -------- ------- Basic earnings per common share - ---------------------------------------------- Earnings before extraordinary item $16,108 $6,557 $5,025 $14,051 $10,564 Average equivalent shares Common shares outstanding 12,049 12,007 12,011 11,612 11,390 Basic earnings per common share $ 1.34 $ 0.55 $ 0.42 $ 1.21 $ 0.93 Diluted earnings per common share - ---------------------------------------------- Earnings before extraordinary item and cumulative effect of a change in accounting principles $16,108 $ 6,557 $ 5,025 $ 14,051 $ 10,564 Average equivalent shares Common shares outstanding 12,049 12,007 12,011 11,612 11,390 Stock options and restricted stock 99 2 119 82 -- ------- ------- ------- -------- --------- Average equivalent shares 12,148 12,009 12,130 11,694 11,390 ------- ------- ------- -------- --------- Diluted earnings per common share $ 1.33 $ 0.55 $ 0.41 $ 1.20 $ 0.93 ------- ------- ------- -------- ---------