Solar Panels: AC vs. DC (2008)
This 2008 article explains the difference between AC (alternating current) and DC (direct current) solar panels, focusing on how solar cells produce DC electricity and the need for inverters to convert it to AC for home use, while also discussing the pros and cons of each system type.
Background
- This page is a simple, illustrated explanation of the difference between AC (alternating current) and DC (direct current) electricity in the context of solar power, written in 2008 when residential solar was still relatively niche.
- **DC (Direct Current):** The type of electricity that solar panels naturally produce. Electrons flow in one direction. Batteries also store and deliver DC power.
- **AC (Alternating Current):** The type of electricity that comes from standard wall outlets and powers most household appliances. Electrons reverse direction many times per second. This is the standard for the electrical grid.
- The key trade-off explained: Solar panels produce DC, but your home uses AC. An **inverter** is needed to convert DC to AC, but that conversion wastes some energy. Using DC appliances directly (e.g., with battery systems) avoids that loss, but such appliances are less common and the power doesn't travel long distances well.
- This was written well before modern "microinverters" and "optimizers" became common, so it reflects an older, simpler view of solar system design.