Negative power flow
During power flow analysis for injection and withdrawal at a Point of Interconnection (POI), grid constraints without additional injection or withdrawal are indicated by a negative power flow MW value.
These negative values signify pre-existing issues independent of new connections.
It is assumed that the utility's reliability process will resolve these known, pre-existing constraints before the connection year for any new interconnection requests. Consequently, these issues should not impact the assessment of capacity available for new connections. However, if these pre-existing issues are not resolved, the effective capacity at the POI is 0 MW.
Risk tolerance
Ultimately, this comes down to risk tolerance and different developers may view risk differently: “How confident am I that the utility can mitigate 2 pre-existing issues before I connect versus 30 pre-existing issues?"