Alpha HPA (ASX:A4N) is set to raise AU$225 million via a two-tranche institutional placement of about 300 million shares, at an issue price of A$0.75 per share, according to a Thursday filing with the Australian bourse.

The offer price represents an 11.2% discount to the stock's last closing price of AU$0.845 per share on Wednesday, the filing said.

Proceeds raised will be used for the construction and commercialization of stage two of the company's HPA First project, and other general corporate purposes, the filing added.

The existing shareholders can also apply for the shares via a share purchase plan (SPP) at the lower of the placement price, and a 2% discount to the five-day volume weighted average price of the company's shares traded up to, and including, the closing date of the SPP.

The second tranche of the placement shares is expected to settle on March 13, the company said.