Case Study: Three Sample Rates

Let's look at a sample set of rates, and how they might be implemented. We'll also look at which components of these rates can be shared.

Rates

The following rates are electric rates offered by a small municipal electric company.

Rate Domestic Rate A Commercial Rate B Power Rate C
Cost of Service Stepped charges, as follows:

$3.08 for the first 10 kWh or less, plus

19.23 cents per kWh for the next 40 kWh, plus

15.44 cents per kWh for the next 150 kWh, plus

14.93 cents per kWh for the next 300 kWh, plus

14.71 cents per kWh for all kWh in excess of 500 kWh

 Stepped charges, as follows:

$2.95 for the first 10 kWh or less, plus

19.23 cents per kWh for the next 40 kWh, plus

18.85 cents per kWh for the next 50 kWh, plus

16.86 cents per kWh for the next 400 kWh, plus

15,45 cents per kWh for the next 3,000 kWh, plus

14.87 cents per kWh for all kWh in excess of 3,500 kWh.		 1. Customer Charge:$52.00

2. Demand: $11.44 per KW

3. Energy: $11.28 cents per KWH

Billing Demand

The Billing Demand for any month shall be the greater of the following:

1. The maximum 15 minute measured demand during the month as measured in kilowatts, or

2. 70% of the maximum 15 minute measured demand as so determined during the preceding 11 months.
Discount Discount of ½ cent per kilowatt-hour after the first 10 kilowatt-hours, if paid on or before the discount expiration date.

For qualifying elderly residents, an additional 10% discount is allowed on the basic rate if paid on or before the discount expiration date and no arrears exist on their accounts.		 Discount of ½ cent per kilowatt-hour after the first 10 kilowatt-hours, if paid on or before the discount expiration date. Discount of 10% exclusive of purchased power and fuel adjustment charge paid on or before the discount expiration date.
Purchased Power and Fuel Adjustment An upward or downward adjustment applied to all kWh sold, based on the total cost of purchased power and fuel compared to the portion of that cost contained in the base rate (11.615 cents/kWh).

The purchase power and fuel adjustment shall be rounded to the sixth decimal place and shall be applied to all kilowatt-hours sold in the following month.		 See Domestic Rate A See Domestic Rate A
Misc. N/A N/A Minimum Bill

The Customer Charge
Taxes State, County, and City Taxes State, County, and City Taxes State, County, and City Taxes

Calculation Rules

Now let's look at these same rates in terms of how we might implement them using calculation rules. The table below lists the type of calculation rule used for each item on the rate.

Rate Domestic Rate A Commercial Rate B Power Rate C
Cost of Service Stepped Charges:

  • Stepped Service Quantity calculation rule
  • Minimum Charge calculation rule (note that the first tier is a fixed price for the first 10 kWh or less)
 Stepped Charges:

  • Stepped Service Quantity calculation rule
  • Minimum Charge calculation rule (note that the first tier is a fixed price for the first 10 kWh or less)
Customer Charge:

  • Flat Charge calculation rule
Demand:

  • Service Quantity calculation rule
  • Math calculation rule (to calculate demand from interval values)*
Energy:

  • Service Quantity calculation rule

*Could be included in either a Pre-Processing or Rate Version Calculation Group
Discount Discount:

  • Apply To calculation rule

Elderly Discount:

  • Apply To calculation rule
 Discount:

  • Apply To calculation rule
 Discount:

  • Apply To calculation rule
Purchased Power and Fuel Adjustment PPF Adjustment:

  • Service Quantity calculation rule

Note: The PPF adjustment rate would be defined as a Bill Factor, updated monthly based on the prior month's total cost. 		PPF Adjustment:

  • Service Quantity calculation rule
 PPF Adjustment:

  • Service Quantity calculation rule
Misc. N/A N/A Minimum Bill:

  • Minimum Charge calculation rule
Taxes State, County, and City Taxes:

  • Apply To calculation rule (one for each type of tax)
State, County, and City Taxes:

  • Apply To calculation rule (one for each type of tax)
State, County, and City Taxes:

  • Apply To calculation rule (one for each type of tax)

Shared Components

Now, let's look at the components of these rates that can be shared.

Discounts: Rates A and B both use the same discount, so we could create a single "AB Discount" calculation rule that could be used with both rates. Note: Either this could be in its own calculation group that is listed among the Rate Version Calculation Groups for each rate, or the group could be referenced by an "Execute Calculation Group" rule which in turn would be included in one of the other Rate Version Calculation Groups used in each rate.

Purchased Power and Fuel Adjustment: Rates A, B, and C all use the same adjustment for purchased power and fuel, so we could create a single "PPF Adjustment" calculation rule that could be used with all three rates. Again, this calculation rule could be in its own calculation group listed on the rate, or in a group referenced by an "Execute Calculation Group" rule included in another group.

Taxes: Rates A, B, and C are all subject to the same taxes, so we could create calculation rules for each type of tax (State, County, and City) in a single group that could be used with all three rates. Again, these calculation rules could be in their own calculation group listed on the rate, or in a group referenced by an "Execute Calculation Group" rule included in another group.