Item 8.01 Other Events.

As previously disclosed in a Form 8-K filed February 20, 2009, Beacon Power Corporation (the "Company" or "Beacon") entered into a Common Stock Purchase Agreement (the "Agreement") whereby the Company agreed to issue to Seaside 88, LP ("Seaside") and Seaside agreed to buy $1 million worth of shares of Beacon Common Stock once each month at a monthly closing on the 20th day of each month (or if that day is not a business day, then on the next business day) for a period of six months commencing on February 20, 2009 at a purchase price equal to 80% of the volume weighted average trading price of the Company's common stock, par value $0.01 per share (the "Common Stock") during the five-day period immediately preceding each monthly issuance, but in no event below $0.20 per share. If in any month the calculated purchase price of Beacon Common Stock would be below $0.20 per share, then the closing for that month will not occur and will not be made up. Beacon may extend the term of the Agreement for up to two additional six month periods under the conditions described in the Agreement. Under the Agreement, on May 20, 2009 Seaside will purchase 1,647,772 shares of the Company's Common Stock at a price per share of $0.60688 having an aggregate purchase price of $1,000,000. Pursuant to the Agreement, the Company will pay Seaside $9,000 in non-accountable expenses.

Item 9.01 Financial Statements and Exhibits.

(d) Exhibits

5.1 Opinion of Edwards Angell Palmer & Dodge LLP

23.2 Consent of Edwards Angell Palmer & Dodge LLP (contained in Exhibit 5.1)

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