Hoku Scientific Inc., the Kapolei-based company that's getting into the polysilicon manufacturing business, said it's issued change orders to increase the size of a planned polysilicon plant in Idaho.

Hoku said an engineering, procurement and construction management services contract with Stone & Webster Inc. and a construction contract with JH Kelly LLC, now calls for a plant capable of producing 3,500 metric tons of polysilicon. Previously the agreements called for a 2,500 metric-ton per-year plant.

Hoku said the plant property outside of Pocatello, Idaho, has been graded and the foundations for the administration and controls buildings were recently poured.