Navigating RTC+B in ERCOT: Unlocking BESS Value for Storage Developers

ERCOT’s Real-Time Co-Optimization Plus Batteries (RTC+B) is a fundamental market shift in how energy and ancillary services are dispatched in ERCOT. By aligning these two markets, ERCOT aims to improve efficiency, reliability, and price formation across the wholesale electricity system. This new framework creates many new opportunities for BESS asset owners and developers, but also raises the bar for operational excellence. Future success in ERCOT will be driven by advanced telemetry and automated bidding strategies that can respond instantly to market signals. Operators that treat RTC+B as simply as a compliance exercise risk financial penalties, while those that embrace it as a strategic opportunity can maximize revenue and strengthen competitive market positioning. This article explores the details of RTC+B and how SYSO is enabling BESS owners to take advantage of this new market structure.

Historically, ERCOT’s ancillary services market has operated within a fixed framework driven by Day-Ahead Market prices, where ancillary service quantities are fixed in advance. Scarcity pricing is handled indirectly through the Operating Reserve Demand Curve (ORDC), which adds value to resources only when shortages occur in real time. While this structure has worked to meet system needs, it has failed to fully adjust to the growing needs of the system as a result of load growth and renewable penetration. 

Under RTC+B, ancillary services will no longer be managed through static Day-Ahead Market procurement, but will rather be dynamically co-optimized alongside energy in the Real-Time Market. This approach replaces the ORDC scarcity framework with Ancillary Services Demand Curves (ASDCs), which will directly price ancillary service shortages in real time. This new construct will prove more accurate price signals to generators and battery storage operators alike. 

At its core, RTC+B introduces true co-optimization of energy and ancillary services, which will be cleared together in real time based on system conditions. Furthermore, batteries will be modeled as unified assets, being able to simultaneously provide load, generation, and reserves. This unlocks new revenue potential for BESS owners in the new ERCOT market design.

In the new market framework, ASDCs assign explicit and continuous demand curves to each ancillary services product (Regup, RegDown, RRS, ECRS, etc.). This allows ERCOT to better account for the true marginal value of reserves in five-minute intervals. For BESS operators, this means that ancillary services will now clear dynamically, with prices updating in real time. 

Another important change is the co-optimization of energy and ancillary services. With RTC+B, ERCOT will evaluate both markets simultaneously to determine whether a resource should provide energy, ancillary services, or a combination of both to maximize system efficiency. This creates a more dynamic and flexible approach for storage assets, allowing them to fully participate in energy arbitrage, frequency regulation, and reserves without separate functions.

The case studies below present market conditions before and after the implementation of RTC+B.

Pre-RTC+B:

The example above illustrates a fictitious scenario in ERCOT, pre-RTC+B. In this case, the battery and gas turbine assets are scheduled in the day-ahead ancillary services market at 20 MW and 15 MW, respectively. When the real-time LMP price spike occurs between 12:00h – 15:00h, ERCOT is forced to dispatch the less efficient combustion turbine asset to meet the energy needs of the system. The more efficient gas turbine asset is not available since it is committed to the static ancillary services market.

Post-RTC+B:

The chart above illustrates this same market dynamic post-RTC+B. Because ancillary services and energy are now co-optimized in the real-time market, ERCOT is able to ramp up the battery’s dispatch to meet the full 35 MW ancillary demand, while swapping the efficiency gas turbine to meet the energy demand. This allows for more efficient market dynamics and overall lower system costs. 

The rollout of RTC+B introduces significant challenges for BESS owners that must be addressed to achieve future success. Two specific areas stand out as the most immediate hurdles: telemetry requirements and operational learning curve. Let’s explore both in more detail. 

Telemetry: ERCOT’s new market framework depends on continuous, high-quality telemetry streams to monitor and dispatch resources in real time. Every second, performance and state of charge data must be accurately transmitted. Outdated communication systems can create risks of delayed or inaccurate signals, leading to misaligned bids, missed dispatch, or performance penalties. Small data errors can lead to significant financial losses over time. 

Operational Learning Curve: RTC+B is a major shift from today’s Day-Ahead fixed ancillary services structure. Asset owners must learn new dispatch logic, ensure seamless integration of forecasting, controls, and communication systems, and be able to respond to real-time price signals. These shifts are making automated bidding almost required to successfully participate in the ERCOT market. Operators who do not adapt to new market rules risk underutilizing assets, leaving revenue on the table, or even incurring penalties for non-performance. 

These new challenges in ERCOT must be met with robust technical infrastructure, deep market experience, and operational expertise. 

In ERCOT’s new structure,  BESS asset owners need a sophisticated operating partner. SYSO’s combination of 24/7 NOC, advanced telemetry integration, and real-time automated bidding technology positions our clients’ storage assets for success under the new rules. By delivering seamless market integration, continuous operational support, and advanced data science, SYSO ensures that storage assets are in compliance. Contact our team today to learn more about our ERCOT market operations and start to develop a plan for success in the new era of RTC+B.