4 ms·

The grid was built and operated on n minus 1 redundancy. Any single transmission line or substation transformer can fail and there should not be an outage. But

The grid was built and operated on n minus 1 redundancy. Any single transmission line or substation transformer can fail and there should not be an outage. But if the other transformer in the same substation fails then you are in the dark. Underinvestment has also led to a loss of redundancy: the substation or redundant transmission path operates over 50% capacity some of the time. Building power lines takes a lot of land, a long time, and is expensive. Redundancy and excess capacity is going to decrease. The system will continue to become less reliable.

bigboomer 7y ago
> Any single transmission line or substation transformer can fail and there should not be an outage. That is not always correct. There are numerous radial lines where the failure of a single transmission line caused numerous downstream substations and customers to experience outages...also, not every substation has 2 transmission/distribution Xfmrs with a Tie...I've seen numerous substations with only 1 Xfmr. > Redundancy and excess capacity is going to decrease. The system will continue to become less reliable. You're absolutely correct on this point...