Exhibit 10.45

AMENDMENT NO. 1 TO

CONTRACT

This Amendment No. 1 (this Amendment) is effective as of May 29, 2007, by and between Hoku
Scientific, Inc., a Delaware corporation (HOKU), MSA Apparatus Construction for Chemical Equipment, Ltd., a company organized and existing under the laws of the United Kingdom (MSA), and GEC
Graeber Engineering Consultants GmbH, a corporation organized and existing under the laws of the Federal Republic of Germany (GEC and together with MSA, the Supplier). HOKU, GEC and MSA are
sometimes referred to individually as a Party or collectively as the Parties.

RECITALS

Whereas, HOKU, and the Supplier are parties to that certain Contract No. GEC/MSA200701 dated as of
January 21, 2007 (the Contract); and

Whereas, the Parties desire to amend the Contract as hereinafter set
forth:

Now, therefore, for good and valuable consideration, the receipt and adequacy of which are hereby acknowledged, the Parties agree as
follows:

AGREEMENT

1. Definitions. Capitalized terms not otherwise defined herein shall have the meaning set forth in the Contract.

2. Amendment of Chapter 4.2.1(A). Chapter 4.2.1(A) of the Contract is hereby amended to read as follows:

65% (Say: sixty-five
percent) of the Contract price at delivery (shipment) of the Equipments, which shall occur after execution of the inspection certificate pursuant to Section 7.5 below, through an irrevocable Letter of Credit issued on or before
September 17, 2007, in favor of the Supplier for the said amount. The Letter of Credit has to allow partial delivery and has no expiry date.

3. Integration. Except for the amendment specifically set forth above, the terms of the Contract shall continue in full force and effect and survive the execution and effectiveness of this Amendment.

[Signature page follows.]



|                      |  |            |  |                      |  |               |  |                      |  |            
|--------------------- |  | ---------- |  | -------------------- |  | ------------- |  | -------------------- |  | -----------
|HOKU Initials & Date: |  | DS 5/29/07 |  | GEC Initials & Date: |  | T.G. 29/05/07 |  | MSA Initials & Date: |  | MS 25/05/07



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In Witness Whereof, HOKU, GEC and MSA have executed this Amendment No. 1 as of the date first set forth above.



|                                                |  |                   |  |                                                                |  |        |  |                      
|----------------------------------------------- |  | ----------------- |  | -------------------------------------------------------------- |  | ------ |  | ---------------------
|GEC  GEC Graeber Engineering Consultants GmbH |  |                   |  | MSA  MSA Apparatus Construction for Chemical Equipment, Ltd.
|                                                |  |                   |  |                                                               
|By:                                             |  | /s/ Thilo Graeber |  |                                                                |  | By:    |  | /s/ Manfred Schirsner
|                                                |  |                   |  |                                                               
|Name:                                           |  | Thilo Graeber     |  |                                                                |  | Name:  |  | Manfred Schirsner    
|                                                |  |                   |  |                                                               
|Title:                                          |  | CFO               |  |                                                                |  | Title: |  | Director             



|                              |  |                   |  |  |  |        |  | 
|----------------------------- |  | ----------------- |  |  |  | ------ |  | 
|HOKU  Hoku Scientific, Inc. |  |                   |  | 
|                              |  |                   |  | 
|By:                           |  | /s/ Dustin Shindo |  |  |  | By:    |  | 
|                              |  |                   |  | 
|Name:                         |  | Dustin Shindo     |  |  |  | Name:  |  | 
|                              |  |                   |  | 
|Title:                        |  | CEO               |  |  |  | Title: |  | 



|                      |  |         |  |                      |  |          |  |                      |  |         
|--------------------- |  | ------- |  | -------------------- |  | -------- |  | -------------------- |  | --------
|HOKU Initials & Date: |  | 5/29/07 |  | GEC Initials & Date: |  | 29/05/07 |  | MSA Initials & Date: |  | 25/05/07



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