Participants in the Solicitation

Clean Earth, Alternus Energy and their respective directors and executive officers may be deemed participants in the solicitation of proxies from Clean Earth’s shareholders in connection with the proposed business combination. Information regarding the directors and executive officers of Clean Earth and their ownership of Clean Earth common stock is set forth in Clean Earth’s final prospectus filed with the SEC on February 23, 2022 in connection with Clean Earth’s initial public offering. Information regarding the persons who may, under SEC rules, be deemed participants in the solicitation of proxies to Clean Earth’s shareholders in connection with the proposed business combination will be s included in the proxy statement that Clean Earth intends to file with the SEC. Additional information regarding the interests of participants in the solicitation of proxies in connection with the proposed business combination will be included in the proxy statement that Clean Earth intends to file with the SEC. You may obtain free copies of these documents as described below.

Additional Information About the proposed business combination and Where to Find It

In connection with the proposed business combination, Clean Earth intends to file relevant materials with the SEC, including a proxy statement. Clean Earth urges its investors, shareholders and other interested persons to read, when available, the proxy statement filed with the SEC and documents incorporated by reference therein because these documents will contain important information about Clean Earth, Alternus Energy and the proposed business combination. The final proxy statement, a proxy card, and other relevant documents will be mailed to the shareholders of Clean Earth as of the record date established for voting on the proposed business combination and will contain important information about the proposed business combination and related matters. Shareholders will also be able to obtain copies of the preliminary proxy statement, the final proxy statement and other relevant materials in connection with the transaction without charge, once available, at the SEC’s website at www.sec.gov or by directing a request to: Clean Earth Acquisition Corp., Attention: Martha Ross, CFO & COO, telephone: (800) 508-1531..

Non-Solicitation

This communication is not a proxy statement or solicitation of a proxy, consent or authorization with respect to any securities or in respect of the proposed business combination and shall not constitute an offer to sell or a solicitation of an offer to buy any securities nor shall there be any sale of securities in any state or jurisdiction in which such offer, solicitation, or sale would be unlawful prior to registration or qualification under the securities laws of any such state or jurisdiction. No offer of securities shall be made except by means of a prospectus meeting the requirements of the Securities Act.