Understanding Curtailment Plans
This article addresses common misconceptions about how to execute curtailment plans after receiving a dispatch.
To succeed in a dispatch, each site must reach full performance at the dispatch start time, and then resume normal operations at the dispatch end time.
During enrollment, Voltus will develop a delivery strategy for each site to meet its performance goal. The delivery strategy is developed around the site’s specific needs, such as its equipment, operating conditions, and financial goals. The delivery strategy is also developed around program rules and the integrator’s control capabilities.
The dispatch object describes the dispatch, not the site’s behavior. If you are a partner or vendor maintaining a dispatch integration, you must coordinate with the shared customer and their Voltus Account Management team to determine how to interpret dispatches and execute the site’s response. Each site may require a different interpretation of dispatch properties.
Examples
Consider Site A that has equipment controlled by Company X. Company X retrieves dispatches from Voltus and sends control signals to Site A. When Site A receives a control signal, it takes five minutes for the equipment to reach the necessary state for full performance. Therefore, when handling dispatches for Site A, Company X should send control signals five minutes before each dispatch’s start time.
Alternatively, consider Site B where the equipment reaches its necessary state instantaneously. Company X should send control signals at the dispatch start time, and no earlier. An early state change could result in reduced earnings.
Dispatch Simulations
Dispatch simulations specify the various conditions that can happen in one or multiple dispatches, such as updates to its start or end time.
What’s a Commitment?
Each site in a dispatch has a commitment value. The commitment is the expected increase in energy available to the grid, whether through load reduction or net export, relative to the site’s registered baseline, and applicable only to this dispatch and this site.
Dispatch integrations should not use the commitment value naively to execute a site’s response.
If Site A is operating at 100MW and receives a dispatch where their commitment is 80MW, reducing their energy consumption to 20MW does not mean that they have fulfilled their commitment. We would also need to consider their historical operating load, their program enrollments, whether there are any overlapping dispatches, and other site-specific details. Instead, Site A should execute its preconfigured delivery strategy.
In some cases, it will be useful to use a commitment value, a program type, or some other detail to execute special behavior for a site. Any such behavior should be planned with the customer and their Voltus Account Management team.