A smart electrical panel is a home's electrical panel made smart: it measures each circuit, switches each circuit on or off from an app, and balances the solar panels, the battery and the car charger. In India, the electrical panel is called the distribution board. It is the box of switches where power comes into the home and splits into separate circuits, such as the kitchen, the bedroom and the air conditioner. This product is sold mainly in the United States so far, where it is called a smart panel or a smart breaker box. Most Indian homes still have an ordinary distribution board.
A normal panel only protects the wires. If a circuit draws too much current, its breaker trips. A smart panel also measures how much each circuit uses, and it can switch a circuit by command. This allows software to make decisions that a person would otherwise make by hand. The software reads the house's total use, the solar power coming in and the state of the battery, and it decides which circuits to run and when.
There is a second reason for the product in the United States. A home there has a main breaker of a fixed size, for example 200 amperes, that limits the total current the house may draw. Adding an electric car charger or a heat pump can push the total above that limit, and replacing the main panel is costly. A smart panel keeps the total below the limit by switching or slowing the less important loads, so the home does not need the larger panel.
Imagine a home in Arizona with rooftop solar and an electric car. At 2 p.m. the panels produce 5 kilowatts, and the house uses 1.5 kilowatts. The smart panel sends the other 3.5 kilowatts to charge the car. When a cloud covers the sun, the panel lowers the charging current, so that the house never draws more than its limit from the grid. During a power cut, it can keep only the important circuits, such as the fridge and the lights, running from the battery.
The panel is connected to the solar inverter, which turns the panels' direct-current power into the alternating current the house uses, to the EV charger, and to a standby generator as a second source. Many panels together can be run as a virtual power plant (VPP), which sells spare power to the grid. It is part of rooftop solar.