Grid prices will go down as demand goes down when people start producing and storing energy themselves. With the cost of solar panels and batteries dropping and production capacity growing exponentially while prices continue to drop, the grid will be less important but still essential to many.

It will also accelerate the demise of coal, gas, and nuclear as they are already too expensive and will have no chance whatsoever in an open market where prices are trending down massively over the next decades. The status quo of course is that they are effectively state protected monopolies currently in many places, which will slow things down in some places and is also the reason you get to pay many times the actual market price per kwh.