This estimator compares the electricity cost of recharging an EV after a vehicle-to-grid export with the revenue or credit earned from that export. It includes charging efficiency so the grid energy purchased for restoration can exceed the battery energy returned.
Use the result to screen whether a V2G event produces a positive gross energy margin before battery wear, demand charges, taxes, program fees, and time-based tariff rules.
1. Enter exported energy
Use the compensated V2G energy quantity.
2. Enter the export credit
Use the payment or bill-credit rate per kilowatt-hour.
3. Enter the recharge rate
Use the electricity rate expected when the battery is restored.
4. Set recharge efficiency
Account for energy lost between the meter and battery.
5. Compare credit and cost
A positive gross margin means the energy credit exceeds recharge electricity cost before other expenses.
A positive value indicates a gross energy-price benefit; a negative value indicates the recharge electricity costs more than the export credit.
Battery degradation, enrollment fees, taxes, and demand charges are not included.
Given: 15 kWh exported at $0.25/kWh, recharge electricity at $0.16/kWh, and 90% efficiency.
Calculation: Credit = 15 × $0.25 = $3.75. Recharge energy = 15 ÷ 0.90 = 16.67 kWh. Cost = 16.67 × $0.16 = $2.67. Margin = $3.75 − $2.67 = $1.08.
Result: Gross energy margin is about $1.08 before other costs.
Not necessarily. The calculator excludes battery wear, equipment cost, taxes, and program charges.
Use the marginal rate for the time when recharging is expected, including time-of-use pricing where applicable.
This version assumes the exported-energy input is the compensated quantity. If compensation is meter-based, export conversion loss is already reflected in that measurement.
Yes, provided the bill credit has the same usable value per kilowatt-hour for your comparison.
Charging losses mean more energy may be purchased from the grid than is stored back in the battery.