Short definitions for every confusing term you'll hit while shopping electricity plans in Texas. If you've seen "TDU", "EFL", or "bill credit" and scratched your head, this glossary is for you.
ERCOT's four highest systemwide 15-minute demand intervals, one in each of June through September. For larger IDR-metered accounts, usage during those four intervals sets the account's share of transmission costs for the following year.
Large Texas accounts that can curtail load on likely 4CP afternoons reduce next year's transmission charges. Predicting the exact intervals is its own cottage industry.
A flat monthly fee charged regardless of usage. Also called "monthly customer charge" or "minimum usage fee". Typically $4.95 to $9.95 per month for residential Texas electricity plans.
For low-usage households (under 600 kWh/month), a $9.95 base charge adds ~1.7¢/kWh to the effective rate all on its own — often more than the difference between plans.
A flat dollar discount applied to your monthly bill ONLY when usage hits a specific kWh threshold (typically 1,000 or 2,000 kWh). Miss by a single kWh and the credit vanishes entirely — the most common trap in Texas electricity.
A plan advertising 9.7¢/kWh with a $100 bill credit at 1,000 kWh has an effective rate of 9.7¢ only if you hit 1,000+ kWh. At 950 kWh the effective rate jumps to 14.2¢ — a 46% increase.
A commercial billing charge based on the highest average power draw (in kW) recorded in any 15-minute interval of the billing cycle, separate from the energy charge for total kWh used.
A restaurant that switches on every oven, fryer, and AC unit at once for fifteen minutes sets its demand charge for the whole month, even if the rest of the month runs quiet.
An electricity market where consumers can choose their retail provider. About 85% of Texas ZIP codes are deregulated. In non-deregulated areas (like most of Austin and San Antonio proper), you have no choice — the local municipal utility is your only option.
Austin Energy and CPS Energy (San Antonio) are municipal utilities, not deregulated REPs. Residents inside their service territories cannot shop for electricity plans; residents in surrounding suburbs often can.
Your actual cost per kilowatt-hour including every fee, charge, credit, and tax. Calculated as total bill divided by total kWh. The only rate that matters for comparing plans honestly.
A plan advertised at 10.9¢/kWh can have an effective rate of 16¢/kWh if you fall below a bill-credit threshold. Voltcheckr computes effective rate automatically from your uploaded bill.
A legally-required one-page disclosure for every Texas retail electricity plan. Shows the rate, fees, term, early termination fee, and the average price per kWh at 500, 1,000, and 2,000 kWh usage levels.
Before signing any Texas electricity contract, always read the EFL — the number in the usage column closest to YOUR average kWh is the only number that matters.
The independent operator that manages the electric grid serving about 90% of Texas. ERCOT handles real-time generation dispatch, grid stability, and the switching process when you change providers.
When you switch electricity providers in Texas, the new REP submits a Move-In request through ERCOT's switching system and ERCOT handles the cancellation of your old service automatically.
A 17-digit number that uniquely identifies your electric meter in the ERCOT system. Required when signing up with a new Texas electricity provider. Printed on every Texas electricity bill.
If you can't find your ESI-ID on your bill, most Texas REPs can look it up from your service address. The ESI-ID never changes, even if you switch providers 10 times.
A penalty charged when you cancel a fixed-term Texas electricity contract before it expires. Typically $150 to $295 depending on the provider and contract length.
Texas law grants a 14-day grace period before your contract end date during which you can switch without paying the ETF. Voltcheckr auto-calculates whether switching mid-contract still saves money net of the ETF.
A Texas electricity plan where the energy rate is locked for the duration of the contract (typically 12, 24, or 36 months). Protects against rate spikes but locks out any savings if wholesale rates drop.
The safest fixed-rate term for most Texas households is 12 months — long enough to lock in predictability, short enough to re-shop when rates shift. 36-month locks are rarely worth the ETF risk.
How suppliers quote contracts that start months in the future: they hedge wholesale power purchases ahead of the start date, so a quote today for a start date next year reflects today's forward market, not a guess.
Forward pricing is why a business can shop its renewal 12 to 18 months early and lock a real rate for a contract that hasn't started yet.
A Texas electricity plan that charges 0¢/kWh during a specified nighttime window (typically 9pm-6am) and a premium rate during paid hours. Only saves money if you shift significant usage to the free window — EV owners, pool pumps, or battery storage households.
You need roughly 37% of your monthly usage to happen in the free window for a free-nights plan to break even against a standard 12¢/kWh fixed plan. Typical households get 15-25% overnight usage.
The month-to-month rate a supplier moves an account to when a fixed contract expires without a renewal. Usually variable or index-based and priced above the expired fixed rate.
Riding out a hot Texas summer on a holdover rate is one of the most common and most avoidable ways businesses overpay. Mark the contract end date and shop early.
A commercial meter that records usage in 15-minute intervals all month long. Demand charges bill off the single highest interval, and IDR data is what suppliers use to price larger accounts on their real usage shape.
Before a renewal, ask your TDU or current provider for 12 months of interval data. It's the raw material for a sharper quote.
A contract structure where the energy rate resets on a schedule, usually monthly, tied to ERCOT wholesale market prices plus a supplier margin. The rate moves with the market, up or down.
Index pricing fits large accounts with someone actively watching the market. A quiet month can be cheap; a tight ERCOT summer month can multiply the energy line.
A kilowatt (kW) measures how fast power is being drawn at one moment; a kilowatt-hour (kWh) measures total energy used over time. Commercial bills charge for both: energy charges bill the kWh, demand charges bill the highest kW.
Think odometer versus speedometer: kWh is the distance you drove this month, kW is the fastest you ever drove.
The unit of electrical energy you're billed for. One kWh is the energy a 1,000-watt appliance uses running for one hour. Your monthly usage is measured in kWh.
A typical Texas household uses between 800 and 2,500 kWh per month, depending on house size, AC load, and season. Summer usage in Houston can be double the winter baseline.
The ratio of energy actually used to the energy that would have been used running at peak demand nonstop: kWh divided by (peak kW times hours in the cycle). Steady operations post high load factors; spiky ones post low ones.
A bakery running ovens around the clock can post a load factor near 70%, while a church that peaks for two services a week can sit under 15%. Some supplier plans set a minimum load factor as an eligibility requirement.
The state-run Texas electricity plan comparison website operated by the Public Utility Commission (PUC). Lists every retail plan available in every deregulated ZIP code, though its sort order favors bill-credit plans that game the display.
Unlike Power to Choose, which sorts by advertised rate at 1,000 kWh, Voltcheckr pulls live supplier rates and ranks plans by effective rate at YOUR actual usage.
The state agency that regulates Texas electricity, telecom, and water utilities. Enforces the Electricity Facts Label requirement, handles consumer complaints, and operates the Power to Choose website.
If you have a dispute with your Texas electricity provider that customer service can't resolve, filing a formal complaint with the PUC is free and typically gets a response within 30 days.
The company you pay for electricity. In deregulated Texas markets, you choose your REP (TXU, Reliant, Gexa, etc.) but the electricity itself flows through the same TDU wires regardless.
Switching REPs does not involve any physical change to your service, meter, or wires. Only the company you pay changes.
A procurement process where multiple suppliers bid against each other to win a business's electricity contract, pushing the price down instead of up. Typically used for accounts above roughly 100,000 kWh a year.
The business provides its ESI ID and usage history, suppliers compete for the load, and the broker's commission is paid by the winning supplier, not the business.
Small regulator-approved surcharges on a TDU's delivery tariff, such as transmission cost recovery, passed through to the bill regardless of which supplier serves the account.
If a rider line looks unfamiliar, check it against the TDU's published tariff sheet. Riders are the same no matter which supplier you pick.
The company that owns the poles, wires, and meters delivering electricity to your home. In Texas, the TDU is separate from your retail provider and cannot be chosen — it's determined by your address.
Houston is served by CenterPoint Energy as its TDU. Dallas and Fort Worth are served by Oncor. You can shop retail electricity providers but your TDU stays the same.
A month-to-month Texas electricity plan where the rate can change with wholesale market conditions. No ETF and no long-term commitment, but significantly more risk during summer price spikes.
Variable-rate plans are a good fallback for customers between contracts (e.g., moving in 2 months) but a terrible default choice because Texas summer wholesale rates can 3x in a single month.
A fixed plan can expire without anyone noticing, and when it does the rate usually rolls onto a pricier month-to-month one. Tell us when it ends and we'll watch that date for you.
