**EXHIBIT 31.2**

**Certification Pursuant toSection 302 of theSarbanes-Oxley Act of 2002**

I, David E. O’Neil,certify that:

1.                I have reviewedthis annual report on Form 10-K/A of SatCon Technology Corporation;

2.                Based on myknowledge, this annual report does not contain any untrue statement of amaterial fact or omit to state a material fact necessary to make the statementsmade, in light of the circumstances under which such statements were made, notmisleading with respect to the period covered by this annual report;

3.                Based on myknowledge, the financial statements, and other financial information includedin this annual report, fairly present in all material respects the financialcondition, results of operations and cash flows of the registrant as of, andfor, the periods presented in this annual report;

4.                The registrant’sother certifying officer and I are responsible for establishing and maintainingdisclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and15d-15(e)) for the registrant and have:

a)                designed suchdisclosure controls and procedures, or caused such disclosure controls andprocedures to be designed under our supervision, to ensure that materialinformation relating to the registrant, including its consolidated subsidiaries,is made known to us by others within those entities, particularly during theperiod in which this annual report is being prepared;

b)               evaluated theeffectiveness of the registrant’s disclosure controls and procedures, andpresented in this annual report our conclusions about the effectiveness of thedisclosure controls and procedures, as of the end of the period covered by thisreport based on such evaluation; and

c)                disclosed in this annual report anychange in the registrant’s internal control over financial reporting thatoccurred during the registrant’s fourth fiscal quarter ended September 30,2005 that has materially affected, or is reasonably likely to materiallyaffect, the registrant’s internal control over financial reporting; and

5.                The registrant’sother certifying officer and I have disclosed, based on our evaluation ofinternal control over financial reporting, with respect to the fourth fiscalquarter ended September 30, 2005 to the registrant’s auditors and theaudit committee of registrant’s board of directors (or persons performing theequivalent functions):

a)                all significantdeficiencies and material weaknesses in the design or operation of internalcontrol over financial reporting which are reasonably likely to adverselyaffect the registrant’s ability to record, process, summarize and reportfinancial information; and

b)               anyfraud, whether or not material, that involves management or other employees whohave a significant role in the registrant’s internal control over financial reporting.

| Dated: February 6, 2006 |   | /s/ David E.  O’Neil                |
|-------------------------|--------|------------------------------------------|
|                    |   | David E. O’Neil                     |
|                    |   | Vice President of  Finance and Treasurer |

 

 

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