X0306 4 2017-05-17 1 0001455684 TPI COMPOSITES, INC TPIC 0001418349 NGP Energy Technology Partners, L.P. 1700 K STREET NW, SUITE 750 WASHINGTON DC 20006 0 0 1 1 Director by Deputization 0001422087 NGP ETP, L.L.C. 1700 K STREET NW, SUITE 750 WASHINGTON DC 20006 0 0 1 0 0001421879 Energy Technology Partners, L.L.C. 1700 K STREET NW, SUITE 750 WASHINGTON DC 20006 0 0 1 0 Common Stock 2017-05-17 4 S 0 1358126 16.35 D 2442190 I See Footnote These securities are held of record by NGP Energy Technology Partners, L.P. ("NGP LP"). NGP ETP, L.L.C. ("NGP ETP") is the general partner of NGP LP and Energy Technology Partners, L.L.C. ("ETP LLC") is the manager of NGP ETP. The Reporting Person is the manager of ETP LLC and may be deemed to share voting and investment power with respect to all shares held by NGP LP. This report on Form 4 is jointly filed by NGP LP, NGP ETP and ETP LLC. Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein for purposes of Rule 16a-1(a) under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), except to the extent of its pecuniary interest therein, if any. This report shall not be deemed an admission that any of the Reporting Persons is a beneficial owner of such securities for the purpose of Section 16 of the Exchange Act, or for any other purpose. /s/ Steven G. Fishbach, Attorney-in-Fact for NGP Energy Technology Partners, L.P. 2017-05-18 /s/ Steven G. Fishbach, Attorney-in-Fact for NGP ETP, L.L.C. 2017-05-18 /s/ Steven G. Fishbach, Attorney-in-Fact for Energy Technology Partners, L.L.C. 2017-05-18