G3 Basic Service Charges

The G3 (Standard - Large Customer) rate is the standard electric rate for large customers with average monthly usage of at least 120,000 kWh per month.

Market Variable Basic Service Charges

Market-based Basic Service Charges for G3 customers equal the sum of a fixed component charge and a market price charge for each calendar month.

The market price charge equals the weighted average of the Real Time Locational Marginal Prices ("LMP") for the WCMA Load Zone (Node 4007) each calendar month. LMPs are hourly wholesale prices in dollars per megawatt-hour (MWh). Wholesale prices are converted to retail prices by adding distribution losses of 3.68% and dividing by 1000 to convert to dollars per kilowatt-hour (kWh).

If you are interested in source data for market price charges, you can access wholesale LMP data on the ISO-NE website.

At the destination page:

• In Step 1, select "Load Zone."
• In Step 2, select "4007_:_.Z.WCMASS."
• In Step 3, select the start and end dates you wish to receive .
• Click "Download CSV" (comma separated values) and save the file locally. You can open the file with any text editor or spreadsheet program, such as Microsoft Excel.

In the data file, the LMP data can be found in the eighth column, which is labeled "Real Time LMP." The twelfth column, labeled "Real Time Status", indicates the Status of the real time pricing ("preliminary" or "final"). The monthly price will be calculated and posted after the end of each month, when all LMP data for the prior are final.

Please note that a single query is limited to 45 days worth of data and that hourly pricing data is only available for the past 12 months.