Yet despite the talk of a borderless currency, a handful of Chinese companies have effectively assumed majority control of the Bitcoin network. They have done so through canny investments and vast farms of computer servers dispersed around the country. The American delegation flew to Beijing because that was where much of the Bitcoin power was concentrated.
Mr. Ng, 36, said he had become an expert in finding cheap energy, often in places where a coal plant or hydroelectric dam was built to support some industrial project that never happened. The Bitcoin mining machines in his facilities use about 38 megawatts of electricity, he said, enough to power a small city.