Assumptions and dates
Every rule the model uses, with the day a person last checked it against its source. A date older than a few months is a reason to ask. Sources and their terms: Data sources and terms. Method: How we calculate.
Regulation
- Market redesign date
- October 01, 2025 (history before it is shown as context only); RegUp / RegDn shown separately from December 01, 2026 at a 50/50 placeholder
Source: PJM regulation market redesign. Last checked 2026-10-20. - Base price path
- $150 per MW-hour in 2026 falling to $35 by 2029, then flat
Source: Modo Energy, PJM regulation market outlook (2026): post-redesign prices fade to about $35/MW as storage saturates the requirement; GridArb's base path reaches that level by 2029, the high path by 2033. Last checked 2026-10-20. - Low price path
- the pre-redesign average falling to the battery's cost floor (about $4.30 per MW-hour: $3 margin adder plus energy losses at 0.25 MWh per MW-hour and $40 per MWh) by 2028
Source: GridArb assumption. Last checked 2026-10-20. - High price path
- the last-12-month average falling to $35 by 2033, never below the base price in any year
Source: Modo Energy, PJM regulation market outlook (2026): post-redesign prices fade to about $35/MW as storage saturates the requirement; GridArb's base path reaches that level by 2029, the high path by 2033. Last checked 2026-10-20. - Cleared-hours share
- min(80%, 750 MW requirement / expected battery fleet); fleet path 2026 600 MW, 2027 2,500 MW, 2028 4,000 MW, 2029 5,000 MW, 2030 onward 7,000 MW; low case 1.5x the fleet, high case 0.5x
Source: PJM, Energy Storage Resource participation paper, and Modo Energy's PJM outlook: expected battery fleet about 600 MW in 2026, 2,500 MW in 2027, 4,000 MW in 2028, 5,000 MW in 2029 and 7,000 MW from 2030, against a regulation requirement of about 750 MW. Last checked 2026-10-20.
Capacity
- Clearing prices used (all at the FERC-approved cap)
- 2026/27 $329.17 per MW-day; 2027/28 $333.44 per MW-day; 2028/29 $325.00 per MW-day; default delivery year 2028/29
Source: PJM Base Residual Auction reports (2026/27 July 2025; 2027/28 December 17, 2025; 2028/29 July 14, 2026). Last checked 2026-10-12. - Price collar
- cap and floor through 2029/30; PJM's uncapped simulation range $530 to $555 per MW-day
Source: FERC order on the PJM collar; PJM auction report. Last checked 2026-10-12. - ELCC storage ratings by delivery year
- 2026/27: 4 h 0.50, 6 h 0.58, 8 h 0.62, 10 h 0.72; 2027/28: 4 h 0.58, 6 h 0.67, 8 h 0.70, 10 h 0.78; 2028/29: 4 h 0.59, 6 h 0.68, 8 h 0.71, 10 h 0.78. A battery under 4 hours is rated as energy / 4 at the 4-hour class (GridArb assumption until confirmed in PJM's ELCC calculator)
Source: PJM ELCC class ratings published with each BRA. Last checked 2026-10-12. - After the collar (fifteen-year view)
- low / base / high $175 / $250 / $500 per MW-day; 4-hour ELCC sliding to 0.40 by 2035
Source: GridArb scenario paths (labelled, not a forecast); PJM long-range preliminary ELCC trend. Last checked 2026-10-12.
NJ GSESP
- Award range and term
- $60,000 to $81,840 per MW-year for 15 years, projects of 5 MW and more; the report's award case uses $60,000 / $75,000 / $81,840, only if awarded; Tranche 2 decision expected December 2026; never in the default total
Source: NJ BPU orders of June 18, 2025 and March 4, 2026. Last checked 2026-10-20.
Federal ITC
- Rate and treatment
- 30% of the battery cost in year 0 (Section 48E), full credit for construction starting by 2033; the interconnection estimate is not credited; a project that fails the foreign-entity (FEOC) rule gets no credit, shown as the user's choice on every report
Source: Section 48E clean electricity investment credit (2026 summary). Last checked 2026-10-12.
Costs
- Battery cost benchmark
- NREL ATB 2025 (Utility-Scale Battery Storage, Moderate, year-2024 values, 2023 USD), OEDI submission 8759, workbook dated 2026-08-27, downloaded 2026-10-12: $361.34 per kW plus $234.01 per kWh (in 2023 dollars, 2024 values), plus a 15% small-project premium; a quote replaces it
Source: NREL Annual Technology Baseline. Last checked 2026-10-12. - Operating assumptions
- fixed O&M 4% of capex a year; usable energy fades 2.5% a year with an augmentation below 80%; NPV at 8% over 15 years
Source: NREL ATB (O&M); GridArb assumptions (fade, augmentation, discount rate). Last checked 2026-10-12. - Cost range on every report
- battery cost -20% and +20%, interconnection estimate held fixed
Source: GridArb assumption. Last checked 2026-10-12. - Import tariff scenario
- battery cost +0% / +25% / +80%, labelled a scenario, not a forecast
Source: GridArb scenario. Last checked 2026-10-27.
Energy arbitrage
- Capture rate
- achievable revenue = 80% of the perfect-foresight optimizer (range 70% to 90%); day-ahead hourly prices only; 2024 and 2025 tested, 2025 the headline year
Source: GridArb assumption (operator capture rates in published PJM battery studies). Last checked 2026-10-12.
Timing
- First operating year (COD) by connection type
- transmission 2029; distribution 2028; btm 2028; every payback and NPV runs from that year; 'if running today' is context only
Source: PJM cycle timelines (Manual 14H); NJ distribution interconnection rules. Last checked 2026-10-20.
Benchmark check
- Industry benchmarks
- first operating year compared with the PJM fleet average of about $62 per kW-month; the 15-year average with a central case of about $84,000 per MW-year; the warning and GridArb's own test fail above 1.5x the central case
Source: Modo Energy, PJM battery revenue publications (2026). Last checked 2026-10-20.
Grid connection
- Screening thresholds and deposits
- feeder kW against planned kW at 1.0 (green) and 0.5 (yellow); nearest substation within 3 and 10 km; queue projects 1 or 3 at the same substation, 3 or 8 within 5 miles; upgrade cost yellow above $150,000 and red above $500,000 per MW; PJM deposits $75,000 plus $4,000 per MW for 0-20 MW; distribution route below 69 kV
Source: GridArb thresholds; PJM Manual 14H, Generation and Transmission Interconnection Process; N.J.A.C. 14:8-5. Last checked 2026-10-20.
Local rules
- NJ municipal moratoriums and bans
- a hand-kept tracker (town, kind, end date, source and date); a report shows a red flag when the site's town is on it
Source: NJ news and municipal sites; see /moratoriums. Last checked 2026-10-27.
Dates are when a person confirmed the value, recorded in the build log; they move only when someone re-checks.