The Obama Administration is now investigating claims by the United Steelworkers Union about whether China is giving its companies an unfair boost as they compete in the global marketplace.
Though officials at Yingli Solar denied that they were receiving help from the Chinese government, back in the U.S., it's a matter of huge dispute.
While the debate grows, so does Yingli's list of American clients. The company's chief told me that they're now sending panels to Texas and Colorado, and they hope to eventually reach all 50 states.
But this isn't just about business, says Liu.
"The heart of why China is going green is not climate change. It's actually national security," said Liu. "We're a net importer of coal, we're a net importer of oil, we're a net importer of gas."
It's one more example of a green industry barreling forward, nearly as fast as those high-speed trains, toward a greener and more profitable China.