Exhibit 11 Environmental Power Corporation Computation of Earnings Per Share December 31, 1998 Income Shares Per Share (Numerator) (Denominator) Amounts ------------------ -------------------- --------------- Three Months Ended December 31, 1998: - ------------------------------------- Loss available to shareholders $(1,703,240) 11,406,783 $(.15) Effect of dividends to preferred stockholders (1,250) ------------------ -------------------- --------------- Basic EPS - loss available to common shareholders (1,704,490) 11,406,783 (.15) Effect of dilutive securities: Assumed exercise of dilutive stock options ------------------ -------------------- --------------- Diluted EPS - loss available to common shareholders $(1,704,490) 11,406,783 $(.15) ================== ==================== =============== Three Months Ended December 31, 1997: - ------------------------------------- Income available to shareholders $ 4,900,751 11,230,696 $ .44 Effect of dividends to preferred stockholders (1,250) ------------------ -------------------- --------------- Basic EPS - income available to common shareholders 4,899,501 11,230,696 .44 Effect of dilutive securities: Assumed exercise of dilutive stock options 132,491 ------------------ -------------------- --------------- Diluted EPS - income available to common shareholders $ 4,899,501 11,363,187 $ .43 ================== ==================== =============== Income (Loss) Shares Per Share (Numerator) (Denominator) Amounts ------------------- -------------------- --------------- Year Ended December 31, 1998: - ----------------------------- Loss available to shareholders $(1,649,186) 11,406,783 $(.14) Effect of dividends to preferred stockholders (5,000) ------------------- -------------------- --------------- Basic EPS - loss available to common shareholders (1,654,186) 11,406,783 (.14) Effect of dilutive securities: Assumed exercise of dilutive stock options ------------------- -------------------- --------------- Diluted EPS - loss available to common shareholders $(1,654,186) 11,406,783 $(.14) =================== ==================== =============== Year Ended December 31, 1997: - ----------------------------- Income available to shareholders $ 4,613,863 11,120,893 $ .41 Effect of dividends to preferred stockholders (30,178) ------------------- -------------------- --------------- Basic EPS - income available to common shareholders 4,583,685 11,120,893 .41 Effect of dilutive securities: Assumed exercise of dilutive stock options 138,972 ------------------- -------------------- --------------- Diluted EPS - income available to common shareholders $ 4,583,685 11,259,865 $ .41 =================== ==================== ===============