What is net metering?
You aren't always using all the power produced by your solar system. In many areas, you can feed this excess energy back into the utility grid in exchange for a credit on your bill. The specifics of net metering depend on your area and utility. This is one of the benefits of a grid-tie system.
How does the battery backup work?
When the sun is out, your batteries are charged by your grid-tie battery backup inverter before feeding the excess energy back into the utility grid. If the power goes out, the power loads you specify are switched from the utility grid to your batteries, allowing them to continue operating.
If your power is going out constantly, your home business is highly dependent on having power, or you have critical loads that need power no matter what, a grid-tie battery backup system is the right choice for you.
Since substantial power may move across On and Off Grid Inverters, attention must be paid to self- heating and efficiency. To minimize energy loss to heat, On and Off Grid Inverters have special circuitry to match the voltage and the frequency of your local utility. In addition to managing the utility power, On and Off Grid Inverters must manage the battery power subsystem.
On and Off Grid Inverters usually include some form of battery charging and battery management circuitry. Batteries have specific charging profiles. Depending on battery state of charge, and their temperature, batteries have optimal charging rates and if not properly controlled they can have their life shortened. An On-Off Grid Inverter should incorporate this circuitry.
Another consideration is the voltage of the backup battery power storage. High power On and Off Grid Inverters tend to use higher voltage battery assemblies. Using higher voltage batteries menad less current has to be ‘stopped up’ household level voltage – typically 110V to 120 V Alternating Current. On and Off Grid Inverters usually have data ports to allow monitoring of operation.