Its 650 MW (megawatts), and over an entire year that equal 5.7 TWh (terawatthours).

Which is similar to a large-ish hydrodam (unless I'm underestimating the size of our local dam)

Edit: I did some digging because I was interested in the 2 million households figure, and it looks like the per household energy consumption in China is (depending on the source, and its unclear if its consumption by those in the house, or just a flat per capital of total energy usage) is between 1/3rd, and 1/10th of where I live. Which means here that solar plant would power 330,000 homes, and there it would power between 1 million, and 4 million homes (obviously Im playing fast and loose with rounding here).