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Grid Flexibility Index · V1 · 2026Q2
Where grid flexibility is worth the most, and where the grid can actually use it.
Opportunity is how much flexibility value a grid needs. Readiness is whether that value can be activated and paid.
Quadrants: · · ·
Questions or feedback on the Index?
Grid Flexibility Index V1. Coming next: utility-level scores within each grid and customer-class lenses.
ERCOT
PinnedActivatedUsing several years of prices instead of the last four quarters would place ERCOT in Ready to scale.
ERCOT is within 0.01 of the quadrant line on the Readiness axis.
Full ranking
Sort by any column. Click a grid to expand its pillars.
| Grid | Opportunity ▼ | Readiness | Quadrant | Opportunity range | Readiness range | ||
|---|---|---|---|---|---|---|---|
| PJM | 6.37 | 4.76 | Untapped | 70% | 6.1-6.8 | 4.1-5.3 | High / Medium |
| SPP | 6.09 | 4.62 | Untapped | 67% | 5.8-6.5 | 4.2-5.4 | High / Medium |
| MISO | 5.63 | 4.80 | Untapped | 57% | 5.4-6.3 | 4.3-5.5 | High / Medium |
| ISO-NE | 5.04 | 4.20 | Untapped | 67% | 4.6-5.9 | 3.7-4.8 | High / Medium |
| NYISO | 4.34 | 6.37 | Activated | 97% | 4.1-4.8 | 5.6-6.9 | High / Medium |
| ERCOT | 3.86 | 5.01 | Activated | 50% | 3.6-4.3 | 4.3-5.7 | High / Medium |
| CAISO | 3.80 | 6.58 | Activated | 100% | 3.7-4.1 | 5.8-6.9 | High / Medium |
How to read the quadrant
Each cell answers a different reader's question.
Opportunity: How much flexibility value a grid needs. Readiness: Whether that value can be activated and paid.
Untapped
high opportunity · low readinessThe reform target. Large, measured value is locked behind rate design and market access. Regulators and advocates should look here first.
Ready to scale
high opportunity · high readinessOperator entry territory. The value is large and the rules let customers reach it.
Monitor
low opportunity · low readinessWatch the momentum. The value and the means to capture it are both still small.
Activated
low opportunity · high readinessLittle untapped value remains relative to how ready the grid is.
Key takeaways
- PJM has the most value on the table for flexible demand (Opportunity 6.37). Its Value score (7.22) is the highest of the seven. Capacity is the largest piece of that value. PJM's capacity auction has cleared at its price ceiling for three straight delivery years: $329.17 for 2026/27, $333.44 for 2027/28, and $325.00 for 2028/29 per megawatt-day. The published PJM score uses the 2027/28 auction. The 2028/29 result is shown for reference and will be considered in a later release. Its Readiness (4.76) sits below the quadrant line, which places PJM in Untapped.#
- California has built the most of what flexibility needs and has the least untapped value left. CAISO leads on Readiness (6.58). Its Infrastructure (9.73) and Rates (6.44) scores are the highest of the seven. California made time-of-use pricing the default residential rate. EIA reports that Southern California Edison's residential enrollment in time-varying pricing programs, time-of-use included, rose from about 20,000 in 2013 to 2.65 million in 2024. CAISO's Opportunity score (3.80) is the lowest of the seven.#
- In ERCOT's competitive market, time-of-use pricing is opt-in. ERCOT ties CAISO for the highest Market access score (8.80), yet its Rates score (2.13) is second lowest. Texas households choose their own retail plan and pay a time-varying price only if they pick one. State rules have also barred indexed pricing plans for residential and small-business customers since February 2022.#
- New York rewards its utilities for growing demand response. NYISO's Institutions score (9.37) is the highest in the release, well above the next grid (ISO-NE, 7.59). New York regulators decouple utility revenue from electricity sales. They also pay earnings incentives tied to demand-response growth.#
- MISO is the Untapped grid closest to Ready to scale. It lands there in 42% of our sensitivity tests, more often than PJM (30%) or SPP (33%). It also has the highest Momentum score (7.61). Congestion became more common on five of the seven grids over the last three years. MISO is the only one where value also became more concentrated in the highest-price hours.#
How the index works
Flexible demand means homes, businesses, and large facilities that shift or cut their electricity use when the grid is strained. It can do some of the work of new power plants and power lines. It pays off only where the grid needs it and the rules let customers take part. The Grid Flexibility Index measures both for the seven US wholesale power markets. It is published as dated, versioned releases. This is the 2026Q2 release, and later updates are published as new releases.
Opportunity measures how much flexibility is worth on a grid: what its markets pay for capacity, energy, and grid services, how stressed the grid is, and which way those pressures are moving. Readiness measures whether that value can reach customers: smart meters, time-varying rates, market access for companies that pool customers, demand-response programs that deliver, and utility incentives that reward it. Both are scored from 1 to 10 and read as a pair. A grid can need flexibility badly and still be unable to use it.
Both scores are built from published sources and documented estimates: ISO market prices, EIA utility filings, NERC reliability assessments, regulator orders and tariffs, and FERC dockets. Some inputs are our own estimates or proxies (the capacity price for three grids, the utility-incentive score for utilities we could not resolve individually), and the methodology page lists the basis and vintage of each factor. Each factor is measured against the same fixed range for every grid. Scores are comparable across grids and from one release to the next.
To test how much the results depend on our own judgment calls, we run a Monte Carlo simulation. It re-scores every grid 20,000 times. Each run varies the category weights, the scoring ranges, and how factors are combined. It also shifts each input within a range set by its data quality or documented uncertainty. The shaded area around each grid spans the middle 80% of its simulated Opportunity and Readiness scores. Quadrant consistency shows how often a grid stays in the same quadrant.
Version 1 scores 19 factors. Wholesale demand-response participation is not scored in Version 1. A replacement measure of market access is under review. The time-varying-rates factor counts residential customers. Every other factor covers all customers or the grid as a whole.
The factors
Opportunity
12 factors · Value 3 · Stress 6 · Momentum 3
Value · 3 factors
- Capacity value. What flexible demand could earn by standing in for the capacity a grid pays generators to guarantee is available at peak.
- Energy arbitrage. What flexible demand could earn shifting electricity use from expensive hours to cheap ones, based on actual wholesale prices.
- Grid services. What flexible demand could earn providing the fast-response support services, like frequency regulation, that keep the grid stable minute to minute.
- Transmission avoidance. What flexible demand could earn by cutting usage during the specific peak hours transmission charges are based on.
Stress · 6 factors
Momentum · 3 factors
Readiness
8 factors, 7 scored in V1 · Infrastructure 1 · Rates 1 · Market access 3 · Programs 2 · Institutions 1
Infrastructure · 1 factor
Rates · 1 factor
Market access · 3 factors
Programs · 2 factors
Institutions · 1 factor
Time-varying-rates data covers 78.8% to 100.0% of residential meters in the utility rosters, depending on the grid. Utility-incentive scores are taken from each utility's rate orders where we have read them and from the average for similar utilities (investor-owned or public power) where we have not, with higher confidence for 6 grids and lower for ISO-NE.
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The scores, methods, and ranges on this page stay open. Subscribe for each release's executive briefing: what changed, why it matters, and one market or utility example. Coming next: utility-level scores within each grid and customer-class lenses for residential, commercial, and large-load customers.
Questions or feedback on the Index?
Grid Flexibility Index V1. Coming next: utility-level scores within each grid and customer-class lenses.
Grid Flexibility Index V1 · 2026Q2 release · trailing 4 quarters ending 2026Q2 · updated 2026-09-27
Corey Balgeman, "Grid Flexibility Index, 2026Q2 release: ERCOT," Grid Flexibility, 2026. https://gridflexibility.fyi/gfi/ercot
License: CC BY 4.0