<TABLE> <S> <C>
<PAGE>
<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM PLUG POWER'S
BALANCE SHEETS AND STATEMENTS OF OPERATIONS, AND IS QUALIFIED IN ITS ENTIRETY BY
REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<S> <C>
<PERIOD-TYPE> 9-MOS
<FISCAL-YEAR-END> DEC-31-2000
<PERIOD-START> JAN-01-2000
<PERIOD-END> SEP-30-2000
<CASH> 92,316,916
<SECURITIES> 12,819,410
<RECEIVABLES> 2,368,243
<ALLOWANCES> 0
<INVENTORY> 2,156,781
<CURRENT-ASSETS> 112,896,624
<PP&E> 34,635,317
<DEPRECIATION> (4,027,627)
<TOTAL-ASSETS> 169,996,881
<CURRENT-LIABILITIES> 9,618,021
<BONDS> 0
0
0
<COMMON> 436,517
<OTHER-SE> 153,639,473
<TOTAL-LIABILITY-AND-EQUITY> 169,996,881
<SALES> 0
<TOTAL-REVENUES> 6,898,348
<CGS> 0
<TOTAL-COSTS> 10,432,264
<OTHER-EXPENSES> 60,130,063
<LOSS-PROVISION> 0
<INTEREST-EXPENSE> 265,439
<INCOME-PRETAX> (63,929,418)
<INCOME-TAX> 0
<INCOME-CONTINUING> (63,929,418)
<DISCONTINUED> 0
<EXTRAORDINARY> 0
<CHANGES> 0
<NET-INCOME> (63,929,418)
<EPS-BASIC> (1.48)
<EPS-DILUTED> (1.48)
</TABLE>