Exhibit 32.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER

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 Quarterly Report on Form 10-Q of Fluence Energy, Inc. (the “Company”) for the quarter ended December 31, 2022 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Julian Nebreda, Chief Executive Officer and President of the Company, certifies, 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.

Date: February 10, 2023

By:	/s/ Julian Nebreda
	Julian Nebreda Chief Executive Officer and President (Principal Executive Officer)