Learn PG&E terms and definitions

This page shows typical energy-related terms to help you better understand your energy statement.

Baseline. Least amount of electricity or natural gas that meets most of the energy needs of the average PG&E customer in a specific service area called a "climate zone." The California Public Utilities Commission (CPUC) sets baseline quantities. The baselines vary depending on customer location, the time of year (summer or winter) and home heating source.

Bundled rate. Rate for customers who receive energy supply and delivery services from PG&E. In contrast, an “unbundled” or “direct access” rate is for customers who receive energy delivery services from PG&E, but also get energy from another supplier.

California Public Utilities Commission (CPUC). Five-member state regulatory body that oversees the electric and natural gas operations of PG&E and other investor-owned utilities. The commission’s goal is to help ensure that customers have safe and reliable energy service at reasonable rates.

Climate zone. One of 10 PG&E service-area sections that have similar geographic and weather characteristics. Approved by the CPUC, climate zones are known as P, Q, R, S, T, V, W, X, Y and Z. We use the zones to create the baseline amounts that go into calculating residential electric and natural gas bills.

Decoupling. California public policy that separates the amount of natural gas and electricity that PG&E and other California investor-owned utilities (IOUs) sell from the profits they earn. The policy is designed to encourage utilities to promote energy-efficiency measures that reduce customer energy use.

Federal Energy Regulatory Commission (FERC). Five-member regulatory agency that oversees:

  • U.S. wholesale energy trading markets
  • National hydropower licensing
  • Interstate natural gas pipeline construction
  • Electric transmission construction


Gas Transmission and Storage Rate Case (GT&S). A regulatory process held every four years before the CPUC. GT&S sets the revenues that PG&E can collect from ratepayers to operate, maintain and expand our natural gas transmission pipelines and storage facilities. Our most recent GT&S rate case covers the period from 2011 through 2014.

General Rate Case (GRC). Regulatory process held every three years before the CPUC. The GRC sets the revenues that PG&E can collect from our ratepayers to operate, maintain and expand our electric generation, electric distribution and natural gas distribution operations. Find out about the 2017 to 2019 GRC, now pending approval. Visit PG&E’s General Rate Case 2017-2019.

Investor-owned utility (IOU). For-profit utility company such as PG&E that shareholders own. An IOU’s operations and earnings are regulated by a state agency like the CPUC.

Nuclear Regulatory Commission (NRC). Five-member federal agency that oversees our Diablo Canyon Power Plant (DCPP) and other nuclear plants around the U.S. The goal of NRC is to help ensure the safety of power-plant operation and on-site storage of nuclear waste.

Publicly-owned utility (POU). Utility owned by the citizens of the area it serves, including:

  • Rural cooperatives
  • Municipal utilities
  • Energy and power marketing authorities


Residential rate tiers. Rate structure for residential electric and natural gas customers of PG&E and other California IOUs. Rate tiers are designed to encourage energy conservation. The more units of energy a customer uses, the higher the price. Rates for each tier are set by the CPUC.