In this second part of the series on How Solar Panels Work we look at how the newly generated electricity makes it way from panel to outlet. As mentioned in the first article the solar panels capture positively charged electrons that create DC electricity or “direct current”. However our grid systems, and therefore our homes, are wired to run on AC electricity or “alternating current”. That means that every solar system requires an inverter to convert the DC you produce into the AC that you use.
The currents from the solar panels are fed through the conduits and merges at the junction box. Once concentrated into a single current, it enters the inverter. Inside, a series of switches flips the current back and forth, until it leaves the inverter in an alternating current.
After the power is converted into functional electricity it flows through an emergency shutdown switch we call the AC disconnect. This is the last control point before the electricity enters the main service panel. Once in the main panel the electricity powers everything in your home that needs it at that very moment and any electricity that is left over flows out of the top where the utility meter sits waiting to send it out to the grid. That process is called “net metering”. (more on that in part three)
There are panels available called “AC panels” but don’t be confused by the name. These panels do not produce AC electricity. They are still the same DC technology, only with an added micro inverter attached to the individual panel. This means that each panel is a self-contained unit and there is no need for an external wall mounted inverter. The individualism of the AC panels also mitigates shading issues and string alignment. Both “DC” and “AC” systems have their advantages in different situations.
Now that we know the technological processes for how solar panels work we must look into the political and economic mechanism that makes solar possible for all of us.