EXHIBIT 32.2


                            CERTIFICATION PURSUANT TO
                             18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002


In connection with the Annual Report of Beacon Power Corporation (the "Company")
on Form  10-K  for the  period  ending  December  31,  2003 as  filed  with  the
Securities and Exchange  Commission on the date hereof (the "Report"),  I, James
M. Spiezio,  Chief  Financial  Officer of the Company,  certify,  pursuant to 18
U.S.C.  section.  1350, as adopted pursuant to section 906 of the Sarbanes-Oxley
Act of 2002, that to the best of my knowledge:

(1) The Report fully complies with the requirements of section 13(a) or 15(d) of
the Securities Exchange Act of 1934; and

(2) The  information  contained in the Report fairly  presents,  in all material
respects, the financial condition and results of operations of the Company.



                                    /s/ James M. Spiezio
                                    James M. Spiezio
                                    Chief Financial Officer

                                    March 30, 2004