POCATELLO, Idaho (AP) — An estimated $400 million polysilicon plant in eastern Idaho now has only eight workers, all security guards. Hoku Materials started building the plant in Pocatello about five years ago, as interest in solar energy began to grow and polysilicon prices rose.

The company predicted it would provide hundreds of higher-paying jobs in the region. But polysilicon prices began to drop, and Hoku laid off 100 employees in May of 2012, just before production began. The Idaho State Journal reports the company's last engineer, Ken Gibbs, stopped working at the plant last month.

Gibbs says he and seven other employees had spent the last several months trying to figure out a joint consolidation plan to save the plant from financial ruin and get it online, but they were unsuccessful.