Time-of-Use Electricity Cost Calculator

How the time-of-use electricity cost calculator works

Peak kWh = total kWh × entered peak share / 100. Off-peak kWh is the remainder. Both scenarios use identical total energy and the same two rates. Peak share may increase or decrease; the signed amount shifted away from peak remains visible.

Each scenario’s peak and off-peak energy charges round half-up to cents separately. Add the same separately rounded fixed fee. Saving is rounded baseline cost minus rounded proposed cost. The summary compares those displayed totals, so a rounded tie is reported as a tie.

A different energy split is an assumption, not proof that operation can shift. Demand charges, tariff calendars, taxes, exports, storage losses, minimum bills and eligibility are excluded. A flat fixed fee does not change the cost difference but remains part of both totals. EIA describes time-varying pricing; no live tariff or peak-hour schedule is supplied here.

Worked example

1,000 kWh with 50% peak costs 150 at an illustrative 0.30/kWh plus 50 off-peak at 0.10/kWh; adding 20 fixed gives 220. At 25% peak, energy charges become 75 and 75, and total becomes 170. The modeled saving is 50. Changing the proposed peak share to 75% instead gives 270 and a −50 saving.

Sources and assumptions

The source material explains the underlying calculation or pricing structure. Entered prices, costs, schedules and scenario choices are your assumptions; this tool does not obtain supplier quotes or predict actual results.

• EIA: electricity prices and time-of-day pricing
• System Advisor Model: electricity energy, demand and fixed charges