It will allow them to store energy and sell it to the grid later during times of oversupply, however there isn't any clear data yet as it is still too early. Everything I have seen is all based on forecasts and financial modelling using the existing pricing system, which I think will actually shift over time inline with the new capabilities of the systems coming as is the case in Europe and the USA.
There haven't been any sustained periods to my knowledge of renewables creating oversupply into the market and being forced to turn off/reduce output. Baseload power from my experience is usually the affected party during periods of oversupply.