This, however, doesn't appear to be good news for coal, as inventory data at key power stations (covering 65% of generation) suggests that a lot of the gain is about hydro generation.
Coal stocks have risen in absolute and days of consumption terms since mid April to ~21 days. Stock building into summer is not unusual, but it hardly seems like that it is voluntary given stock levels are already comfortably high.
While we don't yet have hydro data for April, it was ~20%YoY in March, with anecdotal information suggesting it is strong this year in Southern China. This is bearish, with spot domestic Chinese and seaborne prices likely to fall from already depressed levels.
