ERCOT's ADER pilot lets a thousand home batteries bid as one

I. How your battery becomes one line on a market screen

Start with the unit on your garage wall. It charges from the grid or your roof, sits full, and waits. Under ERCOT's Aggregated Distributed Energy Resources pilot, usually shortened to ADER, your retail provider can bundle that battery with hundreds or thousands of others across the Houston area and present the whole bundle to the wholesale market as a single resource. ERCOT, the Electric Reliability Council of Texas that runs the grid for most of the state, does not see your address. It sees one aggregation with a combined megawatt rating, and it dispatches that aggregation the way it would dispatch a small power plant.

The metering happens behind your meter and at the aggregation level at the same time. Your provider reads how much each home discharged, through the smart meter that CenterPoint Energy, the poles-and-wires utility for most of Houston, already installed on your house. When ERCOT calls for power during a tight afternoon, the aggregator sends the signal, your battery pushes energy back onto the local circuit, and the provider settles the total against the wholesale price. The pilot was approved by the Public Utility Commission of Texas and has been running in phases since 2023, which is to say it is still a test, not a permanent product.

II. The honest math on what it actually pays

Payment tracks the wholesale price at the moment your battery discharges, and that price swings hard. On a mild morning it can sit near a few cents per kilowatt-hour. During a summer scarcity event, when reserves run thin, it can climb toward the system-wide offer cap, which was roughly 5,000 dollars per megawatt-hour at last public report. The money in these programs is made in a handful of stressed hours a year, not steadily, so treat any monthly estimate a salesperson quotes as a hope rather than a schedule.

Then subtract the aggregator's cut, because the provider is taking on the market risk, the telemetry, and the settlement work, and it keeps a share. For most Houston households the realistic result is a modest bill credit or a small payment, not a second income. Whether it beats letting the battery sit idle depends on how often your provider actually dispatches it, how much capacity you let them use, and whether you reserve enough charge for your own backup. If the honest answer is it depends, that is the answer here.

III. Who holds the pieces, and why the caps matter

Four parties touch your battery. Your retail electric provider, acting as the aggregator, signs you up and does the bidding. ERCOT dispatches and settles. CenterPoint owns the wires the power flows across and the meter that counts it. The Public Utility Commission sets the rules and decides whether the pilot graduates into something permanent. None of them can enroll you alone, which is why the practical first question is simply whether your own provider is in the pilot at all.

The caps are the ceiling on all of this. The pilot has limited how much aggregated capacity can participate, on the order of tens of megawatts in its earlier phase, with limits on how large any single aggregation can be. That is deliberate, so the grid operator can study behavior before opening the door wider, but it also means enrollment can close when a phase fills. A cap measured in the low tens of megawatts is a rounding error next to the thousands of megawatts Houston can lose in a single storm, so read the pilot as a proof of concept, not yet as grid-scale backup.

IV. Worth watching this month

1. Watch the PUCT's open-meeting agendas for any item on ADER's next phase or on permanent distributed-resource rules, since that decides whether the pilot grows or expires.

2. Watch ERCOT's ADER project page for a revised participation cap or a notice that the current phase is full, which would close new enrollment.

3. Check whether your own retail provider lists a battery or thermostat program for Houston, because that routine-looking marketing email is the actual gate to joining.

4. Watch CenterPoint's seasonal reliability and storm-readiness updates heading into the next ERCOT summer peak, when any real dispatch is most likely to happen.

5. Keep a loose eye on ERCOT's forecasts for tight-reserve conditions, since those are the hours in which an enrolled battery would earn anything worth noticing.

Sources of record

1. ERCOT, Aggregated Distributed Energy Resources (ADER) pilot project page, Grid operator's own page on how the pilot works, its phases, and participation limits., www.ercot.com/services/programs/load/ader
2. Public Utility Commission of Texas, State regulator that approved and oversees the pilot; search its filings and open-meeting agendas for ADER items., www.puc.texas.gov
3. ERCOT market information and real-time conditions, Grid operator's hub for prices, reserve forecasts, and scarcity conditions that drive any payment., www.ercot.com
4. CenterPoint Energy, outage and storm center, The Houston wires utility that owns your meter; reliability and restoration updates live here., www.centerpointenergy.com/en-us/residential/services/electricity/power-outages
5. U.S. Energy Information Administration, Texas electricity profile, Federal data on Texas generation, prices, and demand for checking the scale claims yourself., www.eia.gov/state/?sid=TX