Reference Document

Data Sources

WattMarkets derives data from official ISO publications. All price data is sourced from publicly available feeds. We do not modify or adjust the underlying data.

ERC

ERCOT

Electric Reliability Council of Texas

Texas

~26M customers
|
~85 GW peak

Data Products Used

Day-Ahead Market Clearing Prices

SettlementDaily

Real-Time Market LMPs

Real-Time5-minute

Settlement Point Prices

SettlementDaily
PJM

PJM

PJM Interconnection

Mid-Atlantic & Midwest (13 states + DC)

~65M customers
|
~165 GW peak

Data Products Used

Day-Ahead LMPs

SettlementDaily

Real-Time LMPs

Real-Time5-minute

Zonal Prices

SettlementDaily
CAI

CAISO

California Independent System Operator

California

~30M customers
|
~52 GW peak

Data Products Used

Day-Ahead LMPs

SettlementDaily

Real-Time LMPs

Real-Time5-minute

Trading Hub Prices

SettlementDaily
NYI

NYISO

New York Independent System Operator

New York State

~19M customers
|
~33 GW peak

Data Products Used

Day-Ahead LBMP

SettlementDaily

Real-Time LBMP

Real-Time5-minute

Zonal Prices

SettlementDaily
ISO

ISONE

ISO New England

New England (6 states)

~15M customers
|
~28 GW peak

Data Products Used

Day-Ahead LMPs

SettlementDaily

Real-Time LMPs

Real-Time5-minute

Hub and Zone Prices

SettlementDaily
MIS

MISO

Midcontinent Independent System Operator

Central U.S. (15 states + Manitoba)

~42M customers
|
~127 GW peak

Data Products Used

Day-Ahead LMPs

SettlementDaily

Real-Time LMPs

Real-Time5-minute

Hub Prices

SettlementDaily
SPP

SPP

Southwest Power Pool

Great Plains (14 states)

~18M customers
|
~54 GW peak

Data Products Used

Day-Ahead LMPs

SettlementDaily

Real-Time LMPs

Real-Time5-minute

Hub Prices

SettlementDaily

Update Frequency

Real-Time Data

Updated every 5 minutes from ISO feeds

Settlement Data

Updated daily after market clearing

Citation Format

WattMarkets. (2025). Grid Price Data for [ISO]. Retrieved [date] from https://wattmarkets.com/settlement/[iso]/[node]/[date]

WattMarkets is not affiliated with any ISO. Data is collected from publicly available sources. While we strive for accuracy, users should verify critical data against official ISO publications. This is not investment advice.