Stand alone versus grid connected solar power systems
You’ve probably run into the terms “stand alone” and “grid connected” in the context of solar panel systems. These are important terms that define how the power you collect from the sun is transferred to your home. So what do these terms mean and which is better?
Let’s start out with grid connected systems. As the name implies, grid connected systems are connected to the local power grid allowing surplus energy collected by the panels to feed back into the grid. For example, if your family is on vacation on a sunny day and the lights and air conditioning are off in your home, you’re going to produce more energy than your house uses and that power will go into the grid. Energy companies will then deduct this power from your energy bill. When your house requires more power than the solar panels are collecting, that power is supplied by the grid. Furthermore, grid connected systems don’t store power; therefore, during the night, the power grid supplies 100% of the power.
In contrast, stand alone solar power systems aren’t connected to the power grid. Instead, they store power in the form of batteries, which are then fed directly into your house. Stand alone system’s independence from the power grid make them an attractive and popular option for remote houses where power grids are not available. However, if you’ve recently bought a pack of batteries you know that they’re not cheap. The high cost of batteries is the principle reason stand alone systems are so expensive.
Due to the high cost of stand alone systems, grid connected systems have become far more popular than stand alone systems in the last five years. It’s possible that stand alone systems will become more popular as the price of batteries decreases but until that happens, grid connected systems will remain the more popular option for buildings on the grid.