EXHIBIT 99.1

Joint Filing Agreement

The undersigned hereby agree that the Statement on the Schedule 13G filed herewith (and any amendments thereto), relating to the common stock of Aspen Aerogels, Inc. is being filed jointly with the Securities and Exchange Commission pursuant to Rule 13d-1(c) under the Securities Exchange Act of 1934, as amended, on behalf of each of the undersigned.

This Agreement may be executed in counterparts and each of such counterparts taken together shall constitute one and the same instrument.

IN WITNESS WHEREOF, the undersigned hereby execute this Agreement as of February 3, 2023.

TELEMARK ASSET MANAGEMENT, LLC
By:	/s/ Brian C. Miley
	Name: Brian C. Miley
	Title: Chief Financial Officer
TELEMARK FUND, LP
By: Telemark Asset Management, LLC, investment adviser
By:	/s/ Brian C. Miley
	Name: Brian C. Miley
	Title: Chief Financial Officer
By:	/s/ Colin McNay
	Name: Colin McNay, in his individual capacity