ok so, even if we assume that you NEED to do this, which is an errant assumption on the basis of "you can just not have that problem through over provisioning" you could use that extra generated power for other things, selling to industry, energy storage, a community center whatever, there are literally endless things you could do with free power, most often you just dump it into heating since it's cheap, and storing it is fairly trivial in something like water.

At worst possible case scenario, your required grid imports are still going to be less than they currently are, which means less external grid maintenance, and less strain.

Granted it's not going to be used year round, unless of course, you over provision production and consume in the winter, and produce in the summer, where now you're getting effectively double the usage, if not more. You probably won't reach peak micro grid infrastructure, but the flexibility providing by something like solar is worth the consideration. A really good example of this is actually the texas power grid, although that is a pretty large power grid, i never said you should island micro generation, just that it's likely going to be beneficial.