Power & Renewables

Powering through outage season: A breakdown of PJM’s WHUB/NIHUB spread

byKenneth Curtis

It’s that time of year when generator and transmission outages are at their peak in PJM. The first half of April has not disappointed volatility-wise as the WHUB/NIHUB spread has set new 30-day highs largely driven by congestion.

Figure 1: Day-ahead WHUB/NIHUB MCC spread for the last 30 days with the constraints driving this spread split out below

Among the top constraints to impact this spread are CHIC_AVE – PRAXAR (138KV) and WEED-MAHO (138KV) in northern Illinois, which discount NIHUB when binding. 

Figure 2: Top three day-ahead binding constraints impacting NIHUB for the last 30 days

Using MUSE’s decomposition views to breakdown the drivers of these constraints by transmission outages, generation and load, we can quickly see if outage season is the driver behind these constraints.

Looking at constraint flows and decompositions for CHIC_AVE – PRAXAR (138KV) we can see the frequency of DA binding has increased with two outages that began in March. These outages don’t roll off until May, indicating this may continue to be a driver of the WHUB/NIHUB spread. 

Figure 3: MUSE constraint decomposition for CHIC_AVE – PRAXAIR (138KV)

Next, let’s dive into WEED-MAHO (138KV), wherewe can see day-ahead binding events increasing in frequency with two outages that began in March. Recently, however, an additional outage has started that is relieving this congestion, decreasing the frequency of DA binding events. This gives a signal that the congestion may alleviate and, in turn, reduce pressure on the WHUB/NIHUB spread.

Figure 3: Real-time/day-ahead shadow prices for WEED-MAHO (138KV) with base decompositions below

Outage analysis on WEED-MAHO (138KV) is possible due to MUSE PJM’s new Base Decomposition feature. With this feature, you can now understand the impact of transmission outages on congestion for any constraint, even ones without constraint flows, giving you a leading indicator for decision making this outage season.

Do you have other spread you would like to analyze? Want to see how MUSE could help you make faster, more confident decisions? Let us help you be the first to know exactly why new constraints bind. 

Picture of Kenneth Curtis

Kenneth Curtis

Kenneth Curtis is a Director of Power Markets at Enverus. His career includes serving as an East Power Trader at Twin Eagle, focusing primarily on the physical flow of power, and as a Power Trader & Asset Manager for EDF Trading, concentrating on the East & West regions.

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