The issue is not that much about the ingress or about a single piece of equipment, as it is that adding new power sources (or consumers) creates topological cha

The issue is not that much about the ingress or about a single piece of equipment, as it is that adding new power sources (or consumers) creates topological changes in the network. That new sources changes the power flow not only locally, but potentially all over the grid. It also changes the way TSOs react to equipment failures: typically, when an equipment like a power line opens, the power flows differently in the network. In order for other equipments not to become overloaded, operators study the network situation and have go-to solutions that involve changing the network topology, rerouting power and, in extreme situations, cutting some consumers. If power sources within the network change rapidly, that study work becomes obsolete fast, and that becomes a problem for operators and their ability to maintain a secure transport grid. TSOs are working on it with both R&D and industrial applications, but that's not a fast process, and sometimes it challenges assumptions that used to be safe, and uncovers big question marks.