Use this glossary to translate common energy terms into plain language. Search by keyword to find a quick definition and move forward with confidence.
Definitions reflect common industry usage. How terms appear on your bill may vary by state, utility and contract structure.
| Term | Definition |
|---|---|
| Ancillary Charges | Regional Transmission Organizations (RTOs) charge load-serving entities fees to provide ancillary services, which include backup power, voltage support and other critical functions. |
| Basis | Part of your natural gas rate that covers your physical cost for transportation, fuel, storage and local production. |
| Capacity Charges | Fees that compensate power plant operators for ensuring that enough resources will be available to meet demand. These may appear as separate items or embedded in supply costs, depending on market and structure. |
| Carbon Free | Electricity generation either does not use fossil fuels or does not emit carbon. |
| Carbon Free Energy (CFE) | Energy which does not produce carbon as a byproduct, including nuclear. |
| Commodity | Type of energy, most commonly electricity or natural gas. |
| CCF (Centum Cubic Feet) | 100 cubic feet of natural gas. 1 CCF ~ 1 therm. |
| Dth (Dekatherm) | Equivalent to 1 million BTUs. 1 Dth ~ 10 Therms. |
| Delivery Charge | Charges from the utility for delivering energy and maintaining infrastructure. |
| Fully Fixed Rate | A supply rate that includes all components of electricity or natural gas costs combined into one rate. |
| Forward Market | A market where commodities are traded for future delivery. |
| Henry Hub | Benchmark location for natural gas pricing in Louisiana used in NYMEX trading. |
| kWh | Kilowatt-hour, the standard unit measuring total electricity usage. |
| Line Losses | Fees for energy lost during transmission and distribution. |
| LNG (Liquified Natural Gas) | Natural gas cooled to liquid form for storage and transport. |
| Load Factor | Ratio of average energy consumption to peak demand. |
| Mcf | 1,000 cubic feet of natural gas. 1 MCF ~ 10 Therms. |
| MMBtu (Metric Million British Thermal Unit) | Standard unit for gas based on heat content. 1 MMBtu ~ 10 Therms. |
| MWh (Megawatt hour) | Megawatt-hour. 1 MWh = 1,000 kWh. |
| Nuclear Energy | Electricity produced from nuclear reactions such as fission. |
| NYMEX (New York Mercantile Exchange) | Benchmark exchange for natural gas pricing (Henry Hub). |
| Passed Through | Charges that may vary and be passed through based on contract terms. |
| Pipelines | Infrastructure used to transport natural gas from production to demand centers. |
| Prompt Month | Contract with the expiration date closest to today. |
| REC (Renewable Energy Certificate) | Renewable Energy Certificate representing one MWh of renewable generation. |
| RPS (Renewable Portfolio Standards) | Renewable Portfolio Standards that require renewable energy adoption. |
| RTO (Retail Transmission Organization) | Transmission system operator managing a multi-state electric grid. |
| Supply Charge | The portion of your bill tied to the energy you purchase from a supplier. |
| Therm | Standard unit used to measure natural gas consumption. |
| Transmission Charges | Cost of moving electricity from power plants to substations. |
| UDC | Utility Distribution Company, commonly known as your utility. |