Single-Phase Power

Single-phase power is the standard type of electrical service delivered to most residential homes in the United States. It provides 120/240 volts through two hot wires and a neutral wire, supplying power for lights, outlets, appliances, and HVAC systems.

The vast majority of residential solar installations in the US connect to single-phase electrical service. Solar inverters for residential use are designed to output single-phase AC power that synchronizes with your home’s electrical system and the utility grid. When sizing a solar system, the inverter must match the voltage and phase configuration of your home’s service. Single-phase service typically supports up to 200 amps, which is sufficient for most homes including those with solar and battery storage. Larger homes or those with particularly high electrical loads (such as multiple EV chargers, pools, and large HVAC systems) may have or need three-phase service. If you are unsure of your service type, check your main service panel or ask your utility — nearly all standard suburban and rural homes in America have single-phase power.