The idea is simple, i think.
If solar panels produce X amount of energy 'too much' is there like a outlet/plug/device or something that can draw a certain amount of enegy but is able to adjust that amount?
If the solar panels produce 2500watt but the house only uses 200watt when nobody is home.
The 2300watt left is being drawn to 'a plug/outlet' and a electric heater for example, or to a usable device.
Then de dishwasher start and the freezer kicks in... now the house use around 600watt, and since some clouds came up only 1900watt is being produced.
so that outlet/plug only draws around 1300watt for that electric heater/plug/outlet/whatever.
I do have a smart electric meter and i'm able to see how much a produce, use and put back on the grid. But since 'putting on the gridd' isn't as intresting as using it myself on the spot i would prefer a device/plug that would adjust it's 'power' to what energy is left over.