Vehicle-to-Grid Revenue Estimator

Introduction: Estimating Vehicle-to-Grid Income From Your EV

Vehicle-to-grid (V2G) participation turns a parked electric vehicle into a potential grid resource. Utilities and aggregators may compensate drivers when their cars export energy at valuable times or remain available as dispatchable capacity. The appeal is straightforward: the grid gains flexible storage while the driver can offset some ownership costs. This V2G estimator focuses on the practical question behind that opportunity—whether expected energy and capacity payments exceed the extra battery wear, program charges, and hardware costs associated with participation.

V2G contracts commonly combine two compensation streams. Energy arbitrage pays for electricity delivered to the grid, while the charging price represents the cost of replacing that energy. Capacity or demand-response payments compensate a driver for making a specified amount of power available during a program period, even when every available hour does not lead to a dispatch. Some programs package other grid services into those payments. Because tariffs, availability requirements, and vehicle limits differ by location and contract, entering the terms that apply to your EV is more useful than relying on a headline payment rate.

Key Inputs That Shape Vehicle-to-Grid Earnings

For this vehicle-to-grid estimate, battery capacity and the usable state-of-charge window set the portion of the pack that can be offered to the program. Reserving energy for driving and battery care means a V2G commitment generally cannot use the entire battery. Round-trip efficiency reduces the modeled energy throughput to account for charging and discharging losses. The charge price and discharge compensation determine the arbitrage spread, while dispatchable power determines the kW on which capacity payments are based.

Full cycles per week describe the expected V2G cycling schedule rather than ordinary driving. Program months per year scale that schedule for seasonal participation, and the availability factor reduces both modeled cycles and capacity payments for time when the vehicle is not expected to be available. The calculator applies the entered degradation cost to total modeled throughput and subtracts annual program fees and hardware costs separately. Use a degradation estimate that reflects your vehicle, operating conditions, warranty considerations, and the depth of cycling you intend to allow.

Formula: Calculating Annual Vehicle-to-Grid Net Revenue

The Vehicle-to-Grid Revenue Estimator first calculates usable battery capacity, then annual equivalent cycles from the weekly cycle count, program months, and availability factor. Annual throughput is usable capacity multiplied by round-trip efficiency and annual cycles. Arbitrage revenue equals that throughput times the difference between discharge compensation and charge price. Capacity revenue equals dispatchable power times the monthly capacity payment, participation months, and availability. Degradation expense applies the per-kWh wear estimate to throughput, and fixed costs are then subtracted to produce net annual revenue.

In this V2G net-revenue expression, Pcap is annual capacity payment, Earb is annual arbitrage revenue, Cd is estimated degradation expense, and F is annual fixed program and hardware cost. The reported breakeven price spread is calculated as degradation expense plus fixed costs divided by total throughput; it is a cost-recovery reference and does not include capacity payments.

Worked Example: Annual Revenue for a 77-kWh Vehicle-to-Grid EV

Consider an electric crossover with a 77 kWh battery enrolled in a V2G program. A 70% usable window makes 53.9 kWh available to the program. Assume 88% round-trip efficiency, an $0.11 per kWh average charging price, and $0.23 per kWh discharge compensation. The vehicle can dispatch 7.2 kW, is scheduled for three full cycles per week over all twelve months, and is expected to be available 90% of the time. The capacity payment is $6 per kW-month, annual program and hardware charges are $120, and estimated battery degradation is $0.05 per kWh of modeled throughput.

Under the estimator’s calculation, the availability adjustment produces 140.4 annual equivalent full cycles. Annual energy throughput is approximately 6,659.45 kWh after the usable-window and efficiency adjustments. The $0.12 per kWh arbitrage spread produces about $799.13 in arbitrage revenue, and capacity payments add $466.56. Estimated degradation expense is about $332.97. After the $120 fixed cost, estimated net annual V2G revenue is about $812.72. If a separate bidirectional charger cost $1,500, dividing that cost by this modeled annual net amount suggests a simple payback of roughly 1.85 years, before considering financing, taxes, rate changes, or program duration.

Comparison Table for Vehicle-to-Grid Participation Choices

These vehicle-to-grid comparisons hold the other example inputs constant so the effect of one change is visible. Reducing the cycle schedule lowers both energy revenue and modeled battery throughput, while the capacity payment remains unchanged because dispatchable power, months, and availability do not change. A higher discharge compensation improves the arbitrage spread, and a lower degradation estimate reduces the cost charged against each modeled kWh. Enter the payment terms and cycling limits offered by your own program rather than treating these illustrations as expected market rates.

How to use: Interpreting Vehicle-to-Grid Revenue Output

When reviewing a Vehicle-to-Grid Revenue Estimator result, look beyond the net-revenue figure at annual equivalent cycles and total energy throughput. Those outputs show the amount of program activity assumed by the calculation and can help frame a discussion of warranty coverage, reserve requirements, and daily driving needs. The breakeven price spread shows how much energy-price margin would be needed to cover modeled degradation and fixed costs through throughput alone; capacity payments may improve the total result independently.

Use the CSV download to share the calculated V2G metrics with fleet managers, household decision-makers, or others evaluating a bidirectional charging arrangement. Revisit the inputs when a tariff, capacity contract, expected availability, or equipment charge changes. If a program pays a separately guaranteed grid-service amount, include it only where its units match the capacity-payment field, which is dollars per kW-month; do not combine a one-time or annual credit with that monthly power rate without converting it first.

Limitations and Assumptions for Vehicle-to-Grid Revenue Estimates

This vehicle-to-grid revenue estimate assumes the entered participation pattern is consistent and does not simulate individual travel days that could make the vehicle unavailable for a dispatch. It treats charging prices and discharge compensation as averages rather than modeling hourly, seasonal, or event-specific prices. Temperature, changing battery capacity, charging constraints, and the timing of energy imports and exports are outside the calculation. Actual battery aging also depends on factors beyond annual throughput, including depth of discharge, temperature, state of charge, and rest periods.

V2G program rules can include enrollment requirements, availability thresholds, dispatch limits, settlement rules, taxes, and equipment compatibility conditions that are not represented in the result. The estimator also does not determine whether a particular vehicle, charger, utility territory, or contract supports bidirectional export. Treat the output as a transparent annual planning scenario: verify the compensation terms, confirm the usable battery reserve that works for your driving, and compare the projected cycling with the guidance and warranty terms that apply to your EV.