First Solar Inc. intends to lay off more than one-quarter of its staff and to restructure operations to focus on newer solar modules, which will lead to at least $500 million in charges and push the company into the red this year.

The restructuring, announced Wednesday in response to steep price declines and lower demand in China, includes about 1,600 layoffs out of the company’s 6,000 workers in the U.S. and abroad.

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