As well as the risks of shoddy kit, there is also a grid stability issue.

Basically, solar can go off an on at a fairly rapid rate, compared to what the grid is designed for. This can lead to instabilities. Either brownouts or spikes in voltage. This can panic some grid equipment and force a shutdown.

What they should do is invest in their infrastructure and make it better able to cope with a distributed supply, distributed load setup. We all know how they feel about investments however!