Three U.S. solar energy companies have declared bankruptcy in the last month, the latest a firm called Solyndra that President Barack Obama praised as a “testament to American ingenuity and dynamism.”

The financial failure of the three American companies has left China as the world's dominant solar industry manufacturer, with nearly 60 percent of the global production capacity. Analysts say Chinese solar producers have been particularly adept at using low-cost loans from state-owned banks and other subsidies to undercut prices charged by companies in other countries.

Solyndra, a solar panel manufacturer in California, secured a $535 million loan guarantee from the U.S. government in 2009 to expand its operations. A year later, Mr. Obama toured its manufacturing plant and he hailed it as a symbol of the U.S. commitment to the expanded use of renewable energy.

But on Wednesday, with the firm having borrowed almost all the guaranteed loan money, Solyndra said it was bankrupt, and was immediately shutting its operations and laying off 1,100 workers. Within the last two weeks, two other U.S. solar firms, SpectraWatt and Evergreen Solar, also have declared they are bankrupt.

The White House said it was disappointed with Solyndra's bankruptcy, but said the U.S. must continue to pursue development of its clean energy industries.