What is islanding?
The first safety issue that comes to everyones mind for small customer-sited systems is a condition called islanding. Islanding is where a portion of the utility system that contains both loads and a generation source is isolated from the remainder of the utility system but remains energised. When this happens with a distributed power system, it is referred to as supported islanding. The safety concern is that if the utility power goes down (perhaps in the event of a major storm), a distributed generation system could continue to unintentionally supply power to a local area. While a utility can be sure that all of its own generation sources are either shut down or isolated from the area that needs work, an island created by a residential system can be out of their control. There are a number of potentially undesirable results of islanding. The principal concern is that a utility line worker will come into contact with a line that is unexpectedly energised. Although line workers are tra