Solar Power Inverter Basics

So what is a solar power inverter and why should you care? Well, it doesn’t make your Home Solar Power System stand on it’s head, that I can assure you.

The solar power inverter is a very important part of your system. Think of it as the key to the front door of your house. Without it you can’t get into your house and enjoy the benefits of having a home. Without an inverter the electricity generated by the solar panels outside your house can’t enter your home to power your appliances. Well, the inverter plays the same type of role in your Home Solar Power System.

The solar power inverter takes the direct current (DC) generated from your solar panels or battery and, using a lot of complex electrical components, turns it into alternating current (AC) that can be used by in-home appliances. Because all solar panels produce electricity in DC, an inverter is required to make the electricity generated by your home solar power system usable by your home appliances.

This means without an inverter your solar panels or batteries can’t effectively transfer their energy into your home for you to use. That’s why the solar power inverter is a crucial part of the system and a component that should not be overlooked.

Two Types of Inverters

There are two basic types of solar power inverters: Stand-Alone and Grid-Connected. Stand-Alone are the ones that simply convert the DC electricity from your solar panels and battery into AC electricity to be used by your home appliances.

The Grid-Connected Inverters are a little bit more complicated and only necessary if you plan on staying tied into your local community power grid (i.e. still receiving power from or returning power to your local utility company). The Grid-Connected inverters have an anti-islanding protection built in. This means that if a fault occurs within your local community’s power grid, that your system disconnects from the grid. This is important because if it did not and you continued to supply power to the local grid while utility workers were working on the system you might electrocute them when the go to work on the power lines.

So the Grid-Connected Inverters are a necessity for those who plan on remaining tied into their local grid. Before you buy a Grid-Connected Inverter make sure that it meets with all the requirements set forth by your local utility company.

How to Choose an Inverter

The solar power inverter is like the brain of your system. You don’t want to skimp on this component or your system might be limited in its capacity to perform up to your needs. Things to take under consideration, in no particular order:

  1. Cost is always a top concern for anyone investing in a system as costs seem to rise quickly. I assure you that you don’t need to refinance your home to get the inverter you need, but realize this is a very important part of your system and should not be bought simply on price.
  2. Efficiency matter more than you think. You can loose much of the efficiency you paid a pretty penny for in your solar panels if you unwisely choose an inverter with a lower efficiency.
  3. Features are always a bonus, but not a necessity, if they have a few extra features great but don’t let this make or break your decision–let them enhance it. Some features to consider/ask about: Low Voltage Disconnect, High Temperature Derating, VA Capacity and Power Factor, Ground Fault Protection Device, Battery Charger, Display Type, and Data Link type.
  4. Voltage Ranges are black and white. The inverter can either handle or cannot handle your installed system. Don’t just think current system capacity when you are choosing your inverter; if you want to expand your system, plan accordingly. A wise choice would be to install fewer solar panels now and invest that money on an inverter that can handle the full capacity of your future/final system.
  5. Operating Temperatures are kind of a no brainer, if you live in Alaska you will be looking for a different type of characteristics than someone in Arizona. This will affect the efficiency of your inverter and your entire system.
  6. Mounting Requirements aren’t a huge consideration but one to think about nonetheless given the space you have allotted your system within your home. You never know if your inverter might need some extra equipment so don’t let this catch you off guard.
  7. A Good Warranty and Support is always a lifesaver. Things break and manufactures don’t have 100% perfect products. So in the event that you get a defective product you don’t want to be left holding the bag.