October 2026 (so far)
In October 2026 so far (12 of 31 days), a 1 MW / 2 MWh battery earned the most from day-ahead energy arbitrage in RECO, $908 (80% of the $1,136 perfect-foresight schedule; $1,400 for a 4-hour battery), and the least in AECO, $778. Capacity revenue at the 2028/29 clearing price added $1,150 in every zone, 56% of the $2,059 total in RECO (energy arbitrage plus capacity, past prices, not a forecast). PJM frequency regulation is upside on top of that and is not in the total: a PJM-wide estimate of $34,560 for the month if the battery cleared 80% of hours ($8,344 low, $34,560 high), a share that falls as more batteries join PJM.
| Zone | Battery | Days | Energy, perfect foresight | Energy, achievable (80%) | Capacity (month share) | Total (energy arbitrage + capacity) | Regulation low / base / high (PJM-wide estimate, if the battery cleared 80% of hours this month; own line, not in the total) | Best day | Worst day |
|---|---|---|---|---|---|---|---|---|---|
| RECO * | 1 MW / 2 MWh | 12 | $1,136 | $908 | $1,150 | $2,059 | $8,344 / $34,560 / $34,560 | 2026-10-01 ($316) | 2026-10-10 ($27) |
| RECO * | 1 MW / 4 MWh | 12 | $1,751 | $1,400 | $2,301 | $3,702 | $8,344 / $34,560 / $34,560 | 2026-10-01 ($481) | 2026-10-10 ($42) |
| PSEG | 1 MW / 2 MWh | 12 | $1,046 | $837 | $1,150 | $1,987 | $8,344 / $34,560 / $34,560 | 2026-10-01 ($263) | 2026-10-10 ($25) |
| PSEG | 1 MW / 4 MWh | 12 | $1,604 | $1,283 | $2,301 | $3,584 | $8,344 / $34,560 / $34,560 | 2026-10-01 ($395) | 2026-10-10 ($38) |
| JCPL | 1 MW / 2 MWh | 12 | $1,041 | $833 | $1,150 | $1,983 | $8,344 / $34,560 / $34,560 | 2026-10-01 ($257) | 2026-10-10 ($24) |
| JCPL | 1 MW / 4 MWh | 12 | $1,593 | $1,275 | $2,301 | $3,576 | $8,344 / $34,560 / $34,560 | 2026-10-01 ($385) | 2026-10-10 ($37) |
| AECO | 1 MW / 2 MWh | 12 | $972 | $778 | $1,150 | $1,928 | $8,344 / $34,560 / $34,560 | 2026-10-01 ($226) | 2026-10-10 ($27) |
| AECO | 1 MW / 4 MWh | 12 | $1,479 | $1,183 | $2,301 | $3,484 | $8,344 / $34,560 / $34,560 | 2026-10-01 ($334) | 2026-10-10 ($40) |
* best zone on the observed total (energy arbitrage plus capacity) for the 1 MW / 2 MWh battery; capacity is PJM-wide, so the zones differ on arbitrage. Energy: day-ahead hourly prices through GridArb's dispatch optimizer (perfect foresight, once-a-day cycle), achievable = 80% of that. Capacity: effective MW x ELCC x the 2028/29 clearing price x days. Regulation: a PJM-wide estimate on its own line, never in the total: the month's forward price at the share of hours a battery would clear, min(80%, PJM's 750 MW requirement / the expected battery fleet of 600 MW in 2026) = 80%; the share falls as more batteries join PJM. Past prices, not a forecast. How we calculate.