I guess we should think about what percent of the power was used for bitcoin mining. If only 1% was used for bitcoin mining that it's pretty hard to say that bitcoin mining was the cause.
Bitcoin mining consumes about 0.6% of global electricity consumption [0]. According to TFA, global mining dropped by 50% from the issues above, so 0.3% of global electricity consumption is in China. China in total produced 5920 TWh in 2016 (last year I could easily get data [1]), out of a global total of 21877 TWh in that same year [2]. China's been growing faster than global trends, but that means that in 2016 they generated ~27% of global electricity (5920/21877). That means your ballpark of about 1% of China's power generation being used on bitcoin (0.3%/27%) is pretty spot on.
