<TABLE> <S> <C>

<PAGE>
<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
CONSOLIDATED BALANCE SHEETS OF TELEGEN CORPORATION AS OF DECEMBER 31, 1999 AND
1998 AND THE CONSOLIDATED STATEMENT OF OPERATIONS FOR THE YEARS ENDED DECEMBER
31, 1999 AND 1998 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH
FINANCIAL STATEMENTS.
</LEGEND>

<S>                             <C>                     <C>
<PERIOD-TYPE>                   12-MOS                   12-MOS
<FISCAL-YEAR-END>                          DEC-31-1999             DEC-31-1998
<PERIOD-START>                             JAN-01-1999             JAN-01-1998
<PERIOD-END>                               DEC-31-1999             DEC-31-1998
<CASH>                                         355,192                      14
<SECURITIES>                                         0                       0
<RECEIVABLES>                                        0                       0
<ALLOWANCES>                                         0                       0
<INVENTORY>                                          0                       0
<CURRENT-ASSETS>                               355,192                      14
<PP&E>                                       1,106,669               1,106,669
<DEPRECIATION>                                 832,491                 672,772
<TOTAL-ASSETS>                                 632,370                 433,911
<CURRENT-LIABILITIES>                        4,972,448               3,675,215
<BONDS>                                              0                       0
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                    23,450,796              23,385,796
<OTHER-SE>                                (23,657,234)            (22,493,460)
<TOTAL-LIABILITY-AND-EQUITY>                   632,370                 433,911
<SALES>                                              0                  57,900
<TOTAL-REVENUES>                                     0                  57,900
<CGS>                                                0                 264,578
<TOTAL-COSTS>                                        0                 264,578
<OTHER-EXPENSES>                             1,168,962               3,333,676
<LOSS-PROVISION>                                     0                       0
<INTEREST-EXPENSE>                                   0               1,115,493
<INCOME-PRETAX>                            (1,162,974)             (4,991,572)
<INCOME-TAX>                                       800                     800
<INCOME-CONTINUING>                        (1,163,774)             (4,992,372)
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                               (1,163,774)             (4,992,372)
<EPS-BASIC>                                     (1.23)                  (6.93)
<EPS-DILUTED>                                   (1.23)                  (6.93)


</TABLE>