At Dartboard, we help battery owners uncover missed revenue opportunities in power markets like ERCOT, where strategies need to evolve constantly.

If you’ve been following ERCOT, you probably know that ancillary-heavy strategies aren’t as profitable as they were in 2023. But shifting to energy arbitrage alone isn’t enough.

What really matters is how well you navigate the tradeoff between the two. So how well are different battery owners positioned? We analyzed performance across ERCOT’s major load zones to see which battery operators adapted best in 2024. Key findings from our analysis:

• Top operators in 2024 didn't just pick one approach - they positioned their assets strategically across multiple strategies.
• Performance patterns varied by zone:
  • West Zone: Jupiter Power positioned its assets across different strategies – most focused on arbitrage, one taking on more ancillaries, all performing well.
  • South Zone: Hunt Energy successfully pushed into arbitrage while keeping ancillary revenue.
  • Coastal Zone: Plus Power adapted quickly while others remained stuck in old strategies.

Let's look closer at how the best operators did.

Optimization Is a Tradeoff – The Best Performers Are on the Frontier

In ERCOT, battery operators face a fundamental risk-return decision. To understand how operators balance risk and reward, we plotted their performance across two dimensions:

• Ancillary Services revenue (y-axis): The percentage of available ancillary revenue captured if the battery consistently cleared the highest-paying ancillary services. An ancillary-dominated strategy is a lower-risk strategy, but returns have been shrinking.
• Energy Arbitrage (x-axis): The percentage of nodal spread captured through energy arbitrage. A higher value here indicates the battery consistently captured the full price spread in its node. An energy-arbitrage dominated strategy comes with greater volatility but bigger upside.

The frontier – the dashed curve in the plots – represents the best achievable tradeoff. This frontier is drawn based on the top-performing batteries at different risk-reward balances.

Think of the frontier as the most efficient balance between risk and reward – if your battery is below it, it could have earned more without additional risk. Batteries on the frontier are maximizing revenue for their chosen risk level.

But it's not just about being on the frontier – it’s about how you’re positioned along it. 

Markets shift constantly, and the best operators don’t just chase one strategy. They spread their assets across different points on the frontier so they can capture value no matter how conditions change. Instead of going all-in on one approach, they balance risk and reward, ensuring they aren’t caught flat footed when the market moves in an unexpected direction.

Frontier Analysis by Load Zone

West Zone: Who Adapted and Who Struggled?

The West Zone saw a mix of strategy changes with some asset owners adjusting efficiently while others left revenue on the table.

How Different Asset Owners Adjusted in 2024:

• Jupiter Power didn’t just shift toward arbitrage – they positioned their assets deliberately across the frontier. Most of their assets moved deeper into arbitrage, but Crossett 1 took the opposite approach, increasing its ancillary revenue share while still staying right on the frontier. That balance ensures they can capture value in different market conditions instead of betting everything on one tradeoff.
• Key Capture Energy took two very different approaches with its West Zone batteries. Worsham Battery remained a pure energy arbitrage asset but failed to increase the percentage of arbitrage revenue captured. Meanwhile, Endurance Park Storage stood out, more than doubling its arbitrage capture rate while maintaining most of its ancillary position. That move kept it firmly on the frontier, making it one of the stronger-positioned assets in Key Capture's portfolio.
• In 2023, all of Gore Street’s assets were clustered in the same spot, fully committed to an ancillary-heavy strategy. In 2024, they attempted to diversify across their three assets, but their shift toward energy arbitrage fell short, and they lost ancillary revenue in the process — keeping them below the frontier. Compared to operators who adapted better, this in-between positioning left earnings on the table.

Key Takeaway: Jupiter spread its assets well across the frontier. Key Capture had one standout asset, but mixed results for the other. Gore Street adjustments fell short, missing out on potential gains.

South Zone: Hunt Leads, Others Lag

While the West Zone showed how different operators approached diversification, the South Zone reveals a different pattern. Some operators successfully shifted toward arbitrage while maintaining ancillary revenues, while others made only incremental adjustments, missing potential gains.

How Key Players Shifted Their Strategy:

• Hunt Energy made a strong push toward arbitrage while keeping a healthy share of ancillaries. Catarina BESS, along with Hunt’s other assets, followed the same strategy. Catarina BESS in particular doubled its arbitrage capture rate while only sacrificing about 5% of its ancillary position. That placed them as one of the top earners in the South.
• Key Capture Energy's South Zone assets saw mixed results. The River Valley batteries maintained strong ancillary position while only slightly dropping their arbitrage capture. In contrast, the Silicon Hill batteries' capture rate fell on both fronts.
• Engie made small adjustments but never fully committed to a strategic shift. Their assets nudged further into arbitrage but stayed clustered below the frontier, leaving revenue on the table. That hesitation proved costly — while others repositioned and captured more value, Engie lagged behind.
• Eolian Energy made a measured shift toward arbitrage while maintaining a strong ancillary share. This balanced positioning helped them stay on the frontier, allowing them to capture value from both revenue streams.

Key Takeaway: Hunt increased arbitrage earnings without sacrificing ancillary revenue. Eolian positioned itself well. Key Capture results were mixed. Engie adjusted, but not enough to stay competitive.

Coastal Zone: Plus Power Leads the Way

The patterns in the South Zone showed the importance of balanced positioning – a theme that continues in the Coastal Zone, although fewer operators successfully made the transition. Plus Power adapted well, while others were slower to reposition, leaving value on the table.

• Plus Power made the decisive move in this zone, shifting further into arbitrage while keeping a solid ancillary share. They increase their arbitrage capture rate from 23% to 36% while preserving most of their ancillary position, staying firmly on the frontier.
• Elsewhere in the Coastal Zone, operators made small adjustments, but none matched Plus Power’s ability to reposition effectively. Some assets remained too anchored to their 2023 strategy, missing opportunities to capture more value.

Key Takeaway: Plus Power captured more arbitrage while staying on the frontier; others in Coastal Zone were slower to adapt and left potential revenue on the table.

Final Thoughts:

• The best operators stayed on the frontier, adjusting their strategy as the market shifted. They weren’t leaving money on the table before – and they still aren’t now.
• Others made strides in 2024, moving toward the frontier – improving their position from 2023 and closing the gap to capture more value.
• Diversification along the frontier is key – since markets shift, spreading assets across different positions ensures stable returns.

Interpreting the Data: Important Context

This analysis provides a performance-based look at how different battery operators are positioned in ERCOT, but there are a few key limitations to keep in mind:

• This analysis is based on actual observed market performance based on ERCOT’s 60-day disclosure data – it does not include revenue earned from virtual offers or bilateral trades.
• Some co-located assets (or any battery, really) may be constrained by hedging structures (e.g., tolls, PPAs) or revenue streams outside of wholesale markets, which aren’t visible in this data.
• Energy arbitrage revenue is based on attainable nodal spreads for each battery. However, nodal spread alone doesn’t tell the full story – some volatility within a node is predictable (weather conditions, load forecasts), while other price movements are unpredictable (extreme weather, unplanned outages, system failures). Some operators may benefit from being in a highly predictable node, while elite operators can still capture energy arbitrage revenue even during unpredictable volatility.

Interested in how your portfolio stacks up? Reach out at info@dartboardenergy.com.