Update RDP tariff mapping functions

[alxsmith]

What

Expand tariff mapping for gas utilities to assign all resstock households the correct tariff including MD gas utilities.

Why

Chesapeake gas has a unique tariff for high use customers.

How (optional)

• research enrollment (participation and auto-enroll or opt-in)
  • If enrollment is very low we will not apply this tariff - report back after research before implementing mapping
• metadata_sb needs to know the annual gas usage for each HH
• we need to pass a threshold value to the tariff mapper that compares the annual usage to the tariff threshold

Deliverables

• tariff maps for all MD gas utilities
• updated tariff mapping script
• test for tiered tariff assignment

[linear]

RDP-235

[alexhyunminlee]

Findings:

Chesapeake utility assigns customers based on their projected usage/historical usage (if sufficient data is available). Proceeding with separate assignment to RES-1 and RES-2 subclasses for Chesapeake and other consolidated utilities (Sandpiper and Elkton gas).

See:

"
I. ASSIGNMENT OF RATE SCHEDULES

Customers:

1. Initial Rate Schedule Assignment:

At the time of Meter activation or in the case of a new Customer at the time of signing,
Company shall estimate the annual usage of Customer (based upon the connected gas
consuming appliances or equipment) and shall assign Customer to the applicable rate
schedule. Company shall not be required to make any refunds to Customers if actual
annual usage is below the minimum usage level of the rate schedule assigned.
Subsequent to service activation, the Customer shall be given reasonable opportunity to
change to another Rate Schedule however, the Company shall not be required to make
refunds for any previous billing under any Rate Schedules selected by the Customer prior
to the time of receipt of a written notice from the Customer requesting to change to
another Rate Schedule.

2. Rate Schedule Review

Service under any rate schedule may be subject to review by the Company. If reviewed,
the Company will determine the annual usage of each Premise at calendar year end and
shall assign each Premise under review to the rate schedule that corresponds to the
Premise’s respective annual Therm usage. Premises with less than twelve months of
billing history will not be re-classed into a different rate schedule. Such rate schedule
assignments shall be effective with the first billing cycle in March and not more than one
change in rates shall be made within any twelve-month period. The Company shall not
be required to make any refunds to Customers if actual annual usage is below the
minimum usage level of the rate schedule assigned. For any high load factor customers,
the Company may apply a +2% variation to the 35% January to March requirement
before moving the Customer out of the high load factor rate class during any rate
schedule review.
"

from https://www.chpkgas.com/wp-content/uploads/2025/12/MarylandConsolidatedTariffs_12-01-2025_ADA.pdf