Exhibit 32.1

NORTHERN POWER SYSTEMS CORP.

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 Quarterly Report on Form 10-Q of Northern Power Systems Corp. (the “Company”) for the quarter ended June 30, 2018 as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, William St. Lawrence, Principal Executive Officer of the Company, hereby certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that, to my knowledge:

(1) The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended; 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: August 16, 2018	By:	/s/ William St. Lawrence
		William St. Lawrence
		Co-interim Chief Executive Officer (Principal Executive Officer)
Date: August 16, 2018	By:	/s/ Reinout G. Oussoren
		Reinout G. Oussoren
		Co-interim Chief Executive Officer (Principal Executive Officer)