On 8/31/20 a unit at the Cardinal facility in PJM (monitored by Live Power) suddenly tripped offline during the evening peak hours. In this blog post we will walk through why the speed and granularity of Live Power data gave traders an advantage in responding to this event before the Real-Time(RT) LMP at Western Hub spiked to $56 at 20:55. We’ll also walk through why having access to historical data from Live Power for this facility allowed traders to be prepared when the RT LMP at Western Hub spiked to $110 the following day (9/1/20) at 10:30 am.
So what happened on 8/31/20? At 20:45 the second unit at Cardinal (a Live Power monitored facility with three units) suddenly tripped offline, meaning that Cardinal was down to one unit during the evening peak hours. This event was confirmed with a corresponding dip in ACE, meaning this was likely an unplanned event. This occurred during a time when load came in lower than forecasted, as well as during a time when load was at a more sustained level than forecasted (i.e., load didn’t drop off as fast as forecasted).
During this same time, the SMITHTON 138 KV SMITHTON-YUKON SLJ-YU constraint was binding and reached its peak shadow price of -$2,000 at 20:45, which was when a unit tripped offline at Cardinal. As seen below, the behavior of this constraint mirrors the generation patterns at Cardinal, which likely means that the unit trip at Cardinal contributed to this constraint binding. The unit trip and the constraint binding also seemed to have a corresponding increase in the RT LMP at Western Hub (green line below), particularly at 20:55 when the RT LMP spiked to $56 as the shadow price for the constraint spiked to -$2,000.
Subscribers to Live Power have access to all of the historical data for the facilities they monitor, which came in handy when analyzing this event. In looking at the history of this constraint and generation at Cardinal since August 1st, we can see that the constraint typically binds when one of the three units at Cardinal goes offline. This is visualized in the scatter plot below where price is on the y-axis and the generation at Cardinal is on the x-axis. As seen below, the shadow price (red) and RT LMP at Western Hub (green) spike when Cardinal is generating around 560 MW, 1160 MW, and 1600 MW, which corresponds with when one of the three units at Cardinal (615-650 MW each) goes offline.
This information was helpful in preparing for what happened the following day (9/1/20) because the second unit at Cardinal never came back online after it tripped on 8/31/20. As expected from the pattern we saw in the scatter plot, the constraint bound again and the RT LMP at Western Hub spiked to $110 at 10:30 am. Having access to both the real time data from Live Power and historical data from Live Power was critical for analyzing and reacting to this event.
In summary, having access to the real time generation data from Live Power in Yes Energy allows traders to quickly react when a unit trips offline at a plant so that they can react before prices do. In addition, by having access to all of the historical data from Live Power, traders can analyze similar events that have happened in the past so that they can be prepared when a similar market event happens in the future (in this case it was the next day).