Reading electricity tariffs: energy, demand, and fixed fees
The quoted cents-per-kWh is usually only part of the bill. Dissect your tariff into energy, demand, fixed, and tax lines — then use the right rate (marginal or effective) for the right question.
What a bill contains
| Charge | Basis | Mining relevance |
|---|---|---|
| Energy | $ per kWh (maybe per time period) | The main variable cost — the number everyone quotes |
| Fixed/account fees | $ per month regardless of use | Sunk for the household; must be spread over total kWh |
| Demand | $ per kW of measured peak (some tariffs) | 24/7 mining holds a high flat peak — see demand lesson |
| Taxes & adjustments | Percentage or per-kWh riders | Vary by jurisdiction; hide inside effective rate |
Your applicable tariff depends on service class, contract, location, and load profile. Another customer's rate card is not yours — pull your own utility's current documents.
Effective vs marginal rate
Round invoice: 1,000 kWh at $0.08/kWh plus a $20 fixed fee = $100 total → effective rate $0.10/kWh. Two different questions need two different numbers: allocating total site cost uses the effective rate; estimating what ONE more hour of mining adds uses the marginal rate (the pure energy price, often $0.08 here). Label which one you used — mixing them is the most common spreadsheet error after power/energy confusion.
See it live on pow.family
The tools' electricity calculator accepts your effective rate and shows the cost floor per coin — the price below which each chain stops paying its power bill.