Pushing electricity onto the grid does come with a cost though and if the electricity is pushed onto the grid at a time when it is not needed, you need to deal

Pushing electricity onto the grid does come with a cost though and if the electricity is pushed onto the grid at a time when it is not needed, you need to deal with it somehow. In some jurisdictions (parts of Australia) they cut you off from the grid if there is an overproduction of solar.