Unsure what solar inverters are? Photovoltaic panels are useless without them. It’s true that residential solar energy systems all start with the panels, which absorb energy in sunlight and convert it into DC power. However, the standard form of electricity used in the home is AC power. Inverters change the DC current in your panels to an AC current you can use in your home. So, when you’re shopping for the entire system, don’t forget to ask questions and do the research on inverters, too.

When shopping for an inverter, check to see that it’s compatible with your solar panels and that it meets your requirements for efficiency and power. Here are some checkpoints you can go through to make sure a potential inverter is the right fit.

• The inverter should match the wattage output of your solar panels. Check the maximum wattage output of your solar panel array and match this figure to your inverter’s output. To get an idea of the range of wattage capacities, a 100-watt inverter can power a portable laptop and a 10 kilowatt inverter can independently manage your home’s power.
• Check for Surge Power. This will enable your inverter to power up with spurts of energy for large appliances that guzzle a lot of electricity.
• Inevitably, energy will be lost during the conversion process. Some inverters lose more energy than others. An inverter with at least 90 percent efficiency is a safe bet.
• Look for automatic features. The inverter needs power to run, and keeping it on at all times will drain unnecessary power. With automatic features, the inverter will turn off on its own when there is low or no energy being used in the home, and will turn back on once power is needed.
• Finally, check for a battery bank. As just mentioned, the inverter needs power from a battery to run. With a battery bank, the inverter can direct a small fraction of the energy it converts to recharge itself.

It’s also important to remember that more than one kind of inverter exists, and you will choose one over the other depending on your overall system plan. Most homeowners are grid-connected and use synchronous inverters that apply energy to the home’s distribution panel. From there it can be used in the home or flow back to the grid. Homeowners who plan to take advantage of net metering should use synchronous inverters.

Standalone inverters are the variety used for off-the-grid homes, while multifunction inverters are connected to both a battery bank and a standby generator.

Popular brands of inverters include Beacon Power, SMA, PV Powered, Xantrex, Fronius, and Exeltech.

Links:
Introduction to Inverters
Inverter Comparison Shopping: Advice

Posted on January 29th in Solar Products by Renee.