| In Part 3 of this series, covering solar power and | | | | connected. The panel contains labeled breakers for |
| how it works, we began our discussion of the | | | | every electrical circuit routed throughout the building, |
| grid-tied system with battery backup, covering the | | | | and these breakers are used to disconnect the |
| components from the PV panels to the battery bank | | | | electricity for any servicing that may need to be |
| and associated items. Here, we'll complete our | | | | done, and to also prevent electrical fires by |
| discussion of this particular type of solar power | | | | disconnecting a circuit should it become overloaded. |
| system and describe the remaining components. | | | | In the same way that a building's electrical wiring |
| Grid-tied - A Definition We've defined this previously, | | | | must be routed through an AC breaker panel, the |
| but, in case you missed it, in brief, the solar power | | | | electrical output from an inverter must likewise be |
| system produces electrical power which is passed to | | | | controlled by an AC circuit breaker, also known as an |
| the utility grid, and then, when needed, from the grid | | | | AC disconnect. This is also used to disconnect the |
| back into the home, hence, grid-tied, also called | | | | inverter for servicing purposes, and to prevent the |
| grid-intertied. | | | | circuit from being overloaded. |
| Components From The Battery To The Utility Grid | | | | 4. Kilowatt Hour Meter |
| 1. DC Disconnect | | | | A bi-directional kilowatt hour meter is exactly what |
| This is required in a system with a battery backup to | | | | you need if you have a grid-tied solar power system |
| allow the inverter to be disconnected from the | | | | because it provides you with information about how |
| battery for service or in case of an emergency, and | | | | much electricity you are pulling from the grid and how |
| protects the wiring from electrical fires. | | | | much electricity you're pumping back into the grid |
| 2. Inverter | | | | courtesy of your solar power system. Most utility |
| Since the power produced by the solar panels is DC | | | | companies will provide these free of charge. |
| (Direct Current) and since most homes use AC | | | | This is by far the most complex and most expensive |
| (Alternating Current) to power household appliances, | | | | of the various configurations possible for solar power |
| there has to be a way to convert DC into AC - take | | | | systems. The advantage to this type of system, |
| a bow, the hard-working, greatly appreciated inverter. | | | | however, is that it gives the household almost |
| 3. AC Breaker Panel/Inverter AC Disconnect | | | | complete energy independence, since the battery is |
| The AC breaker panel is where a building's electrical | | | | available to provide power in case of an outage on |
| wiring and the supplier of the building's electricity, | | | | the grid. |
| whether that's the grid or a solar power system, are | | | | |