Quick definition
A basic solar inverter only does one job: convert DC power from panels into AC power for your home or the grid. A bidirectional inverter can also run that conversion in reverse, taking AC power and turning it back into DC to charge a battery.
This two-way capability is what makes battery charging, and technologies like vehicle-to-home power, possible at all.
At a glance: a hybrid inverter is the most common consumer product built around bidirectional conversion, combining solar input, battery charging, and battery discharging in one box.
Why it matters
Think about what a battery actually needs to do. During the day, it needs to absorb surplus solar power, converting AC or DC input into stored DC energy. At night or during an outage, it needs to send that stored energy back out as usable AC power. That's two opposite conversion jobs, and a standard one-way inverter simply isn't built to do both.
This is exactly why battery-equipped systems, whether AC-coupled or DC-coupled, always rely on bidirectional inverter hardware somewhere in the design. In an AC-coupled system, the battery's own inverter handles the two-way conversion. In a hybrid inverter setup, one combined bidirectional unit manages solar, battery charging, and battery discharging together, the kind of advanced power electronics NREL's own grid research program studies as it becomes standard rather than specialized equipment.
The same principle extends to vehicle-to-home and vehicle-to-grid technology. An EV battery is enormous compared to a typical home battery, and a bidirectional inverter is what lets that stored energy flow back out of the car to power a house during an outage, or even sell power back to the grid, a use case the Department of Energy covers directly in its guidance on EVs as mobile storage.
Where you'll see this
If you're sizing a hybrid inverter for a new battery system, the hybrid inverter sizing calculator matches inverter capacity to your battery and solar array.
For EV owners exploring vehicle-to-home backup power, the bidirectional charging V2H payback calculator estimates whether the added equipment cost pays off through backup value and potential utility savings.
This term comes up any time a quote includes battery storage, in any V2H or V2G equipment discussion, and any time an installer explains why a battery needs different inverter hardware than a solar-only system.
Related terms
Frequently asked
A hybrid inverter is a common example of a bidirectional inverter, built specifically to manage solar input, battery charging, and battery discharging all in one unit. Not every bidirectional inverter is marketed as a hybrid inverter, but most hybrid inverters are bidirectional by design.
Yes, in some form. Charging a battery from AC power and discharging it back to AC power both require converting electricity in each direction, which is exactly what a bidirectional inverter does, whether it's built into the battery unit or sold as a separate hybrid inverter.
V2H setups need a bidirectional inverter to convert power flowing out of the EV's battery back into usable AC power for the home, the reverse of normal EV charging. This is separate hardware from a standard EV charger, which only sends power one way into the vehicle.
Generally yes, since they contain more complex power electronics to safely manage current in both directions. The added cost is usually worth it for anyone adding battery storage or bidirectional EV charging, since a standard one-way inverter simply can't do that job.