Natural gas glossary for Georgia customers: therms, CCF, MRC, marketer, LDC, fixed and variable rates explained.
Georgia gas offers are full of jargon, and some of it is doing real work — the difference between a marketer and a utility, or between a therm and a CCF, changes what an offer actually means. These are the terms worth knowing before you compare Georgia natural gas rates.
Therm — a unit of heat energy, roughly the energy in 100 cubic feet of natural gas. Rates are quoted per therm and usage is billed in therms.
CCF — one hundred cubic feet, a unit of volume. Your meter measures CCF; the utility converts it to therms using a heat content factor, usually close to 1.0.
MCF — one thousand cubic feet. More common in commercial and wholesale contexts than on a residential bill.
BTU — British Thermal Unit, the heat needed to raise one pound of water by one degree Fahrenheit. A therm is 100,000 BTU.
Heat content factor — the multiplier converting CCF to therms, reflecting that not all gas carries identical energy.
Marketer — the certificated company that sells you gas and bills you for it. In Georgia this is who you choose and who competes on price.
LDC (local distribution company) — the utility that owns the pipes, reads the meter and responds to emergencies. For most of Georgia that is Atlanta Gas Light. It does not sell gas.
Regulated provider — the marketer designated to serve customers who cannot qualify with a competitive one, at a rate set with regulatory involvement. See poor credit? you have options.
Georgia PSC — the Public Service Commission, which regulates delivery charges and enforces consumer protections.
Supply or commodity charge — your per-therm rate multiplied by therms used. The competitive part of the bill.
MRC (monthly recurring charge) — also customer service charge. A flat monthly marketer fee billed whether or not you use gas, typically $5–$10. Frequently decides which plan is actually cheapest — see the natural gas calculator.
Base charge — a fixed monthly AGL delivery charge tied to your home’s design day capacity, set by the PSC and identical across marketers.
Design day capacity — an estimate of your home’s peak demand on the coldest expected day. It drives the base charge and is not your actual usage.
AGL delivery charge — the cost of moving gas through the distribution system. Also PSC-set and identical across marketers.
Fixed rate — the per-therm rate is locked for the contract term.
Variable rate — the rate can change monthly at the marketer’s discretion, with no cap.
Introductory rate — a temporary low rate that reverts to a standard, usually higher, rate.
Prepaid — pay before you use. Normally no credit check, no deposit and often no MRC, at a higher per-therm rate.
Early termination fee — charged for leaving a fixed plan before the term ends, commonly $50–$150.
Evergreen or rollover — the automatic move to a month-to-month variable rate when a fixed term expires. The most common cause of an unexpectedly high bill.
Slamming — switching your marketer without authorisation. Prohibited; see your consumer protections.
Budget or levelized billing — equal monthly payments averaging your annual cost, trued up periodically. Smooths the bill; does not reduce it.
Mercaptan — the odorant added to otherwise odourless gas to make leaks detectable. The rotten-egg smell. See do you smell natural gas?
811 — the number to call before digging so buried lines are marked.