Solar Glossary

AC vs DC Electricity

DC (direct current) is what solar panels produce; AC (alternating current) is what your home and the grid use — an inverter converts between the two.

AC vs DC Electricity explained

Solar panels generate DC (direct current) electricity — current that flows in one direction, like from a battery. Your home appliances and the national grid run on AC (alternating current) — electricity that rapidly reverses direction (50 times per second in the UK, 60Hz in the US).

An inverter is the device that converts the DC output from your solar panels into AC power your home can use. This conversion isn't perfectly efficient — typical string inverters operate at 95–98% efficiency, meaning 2–5% of your solar generation is lost in the conversion process.

Why does this matter?

  • String inverters convert all panel DC output centrally
  • Microinverters convert DC to AC at each panel — reducing wiring losses
  • Battery storage: most home batteries store DC power. A DC-coupled system (via hybrid inverter) stores solar energy without conversion loss. An AC-coupled system (like a Tesla Powerwall on an existing solar setup) converts DC→AC→DC→AC, losing ~10–15% in the round trip

The AC/DC distinction also matters for EV charging: most home EV chargers use AC, but some higher-powered chargers convert to DC internally. Understanding this helps you optimise how your solar power flows through your home.

How this affects your solar decision

Understanding AC vs DC helps you grasp how inverter choice and battery coupling affect your system's efficiency. Use the Solar Estimator to explore the right inverter setup for your needs.

Explore inverter options for your solar systemSolar Estimator

Related terms

String InverterA string inverter is a single central device that converts DC electricity from multiple solar panels wired together in a series (a "string") into AC electricity for home use.MicroinverterA microinverter is a small inverter fitted to each individual solar panel, converting DC to AC power at the panel itself rather than in a central unit.Hybrid InverterA hybrid inverter combines a solar inverter and a battery inverter in one unit, managing power flow between your solar panels, battery storage, home, and the grid.AC-Coupled vs DC-CoupledAC-coupled and DC-coupled are the two ways a solar battery can be connected to your system — DC coupling (via a hybrid inverter) is more efficient, while AC coupling allows batteries to be added to existing solar systems.
Back to Solar GlossarySolar Estimator