I've been pondering a idea: why not let my car sell electricity to the grid during peak usage times and recharge when prices are low?

Here's the scenario. After work, I pull into a charging station, but I’m not in a rush to charge. 7 PM is peak electricity demand, and prices are sky-high. I set my requirements—must charge to 90% before leaving tomorrow morning—and then I wait.

The key point is this. My electric vehicle can discharge back to the grid. The process works like this: the charging station connects with the vehicle’s BMS (Battery Management System), and an intermediary reads the current battery level and electricity prices. I input a time constraint (e.g., must have 90% charge by 7 AM), and the system starts working—during peak hours, it instructs the charger to discharge back to the grid, sending 10kWh of power and earning about 5 dollars.

But there's a critical issue: how to ensure that the electricity I send out truly comes from the battery and not from some sneaky diesel generator? This requires zero-knowledge proofs for verification. By analyzing the voltage drop curve of the BMS, the system can prove that the power was indeed discharged from the battery, with no cheating possible.

At 3 AM, electricity prices drop to 1 dollar per kWh, and the charger begins replenishing. Charging 20 kWh costs only 2 dollars, and the battery is full again. Doing the math: I net a profit of 3 dollars, and the car is fully charged.

It sounds perfect, but there's a real-world issue we must face—frequent charge and discharge cycles can impact battery lifespan. Therefore, this system’s algorithm must factor in the actual depreciation cost of the battery. Only when the price difference is large enough to cover the depreciation will the system execute discharging. In other words, arbitrage isn’t possible every peak; you have to wait for truly profitable opportunities.

This approach offers opportunities for Tesla owners, charging station operators, and even professional arbitrage traders. The key is to seamlessly connect on-chain verification with real-world charge/discharge processes, making every kilowatt-hour provable and traceable.