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As Markets+ continues to evolve, many participants are asking how Inter-Entity Settlement Scheduling Agreements (IESSAs) fit alongside interchange transactions, and how these concepts interact with contracts, e-tags, and settlement areas. Below, I’ll walk through some of the most common questions I’ve received from users, breaking down the rules and providing practical examples.
What is an IESSA?
An Internal Energy Schedule Settlement Adjustment (IESSA) is a mechanism in Markets+ that allows Market Participants to request settlement adjustments for energy schedules that both source and sink within the Markets+ footprint.
- The IESSA reflects a bilateral contract between two parties, where the buyer and seller agree to transfer energy at a specified Settlement Location.
- The transaction must represent a physical transfer of energy, with title passing from seller to buyer at the Settlement Location.
- Importantly, IESSAs do not require a resource to self-commit or prevent it from participating economically in the market.
In short: an IESSA is a settlement tool that ensures bilateral energy schedules are properly reflected in Markets+ settlements.
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What is the maximum contract name length for an IESSA?
Markets+ protocols do not explicitly define a maximum contract name length for IESSAs. Instead, the focus is on ensuring that the contract is properly represented in the e-tag and settlement submission. In practice, contract naming conventions are typically constrained by e-tagging systems (OATI), which allow up to 16 characters for contract IDs.
Are IESSAs required to be between two Market Participants?
Yes. An IESSA represents a bilateral transaction between two Market Participants (MPs). Both the buyer and seller must be registered in Markets+ and identified on the e-tag for the transaction to be valid.
Do IESSAs require e-tags?
Yes. For the Market Operator to process an IESSA, the transacting parties must submit an e-tag that reflects:
- The buyer and seller pair,
- The Settlement Location, and
- The physical path within the Markets+ footprint.
The e-tag ensures that the MW quantity in the IESSA does not exceed the underlying physical schedule and that the buyer and seller are adjacent on the market path.
What is a use case for IESSA? How does it work in Markets+?
A common use case is when two Market Participants have a bilateral contract for energy delivery within the Markets+ footprint. For example:
- MP A agrees to sell 50 MW to MP B at Settlement Location L1.
- Both parties submit an IESSA with the contract details and an e-tag showing the physical path.
- In settlement, MP A’s load obligation increases by 50 MW, while MP B’s decreases by 50 MW at L1.
This ensures that the bilateral contract is honored in Markets+ settlements, while still allowing both parties to participate in the broader market.
Define interchange transactions. How do they compare to IESSAs?
An interchange transaction is any energy transaction that crosses the boundary of the Markets+ footprint and requires checkout with an external Balancing Authority Area (BAA). This includes imports, exports, and through transactions.
Key differences between IESSAs and interchange transactions:
- IESSA: Internal to Markets+, between two MPs, requires e-tag, reflects bilateral contracts within the footprint.
- Interchange: Crosses Markets+ boundaries, involves external BAAs, and is scheduled as import/export/through transactions.
Think of IESSAs as internal bilateral settlement tools, while interchange transactions are external boundary schedules.
What is a Settlement Area in Markets+?
A Settlement Area is a defined region within Markets+ where meter data is collected and used for settlement. Each Settlement Area contains one or more Meter Settlement Locations, which are the specific points where load and generation are measured.
If we only have one load point (aggregated), would we end up with only one Settlement Area?
Yes. If your load is aggregated to a single point, you would typically have one Settlement Area with one Meter Settlement Location. This simplifies settlement, as all load is measured and settled at that single point.
What is a bilateral transaction? Do bilateral transactions need to be of a certain term?
A bilateral transaction is simply an agreement between two parties to buy and sell energy outside of the centralized market.
- In Markets+, bilateral transactions can be short-term (hourly, daily) or long-term (monthly, seasonal, annual).
- The key requirement is that if the bilateral is to be reflected in Markets+ settlements (via IESSA), it must be physically supported by an e-tag and submitted with the required details.
Key Takeaways
- IESSAs are internal settlement adjustments for bilateral contracts within Markets+.
- Interchange transactions are external schedules crossing the Markets+ footprint.
- E-tags are required for IESSAs to validate the physical path and contract.
- Settlement Areas define where load and generation are measured; if you aggregate load, you may only have one Settlement Area.
- Bilateral transactions can be of any term, but must be properly tagged and submitted to be reflected in Markets+ settlements.
👉 If you’re navigating IESSAs, interchange, or settlement area setup in Markets+, PCI’s Markets+ solutions can help automate e-tag validation, settlement reporting, and bilateral contract management—reducing risk and ensuring compliance.
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