If you are looking into a solar panel system or even if you already have one, you may be curious about solar batteries and whether you should include them in your system.

Solar Batteries

The simple answer is yes, they are worth considering.

What Are Solar Batteries?

Solar batteries are effectively similar to car batteries. However, they are generally larger and deep-cycle batteries. This means they are used to be emptied and refilled on a regular basis and their performance won’t suffer. The solar battery is fitted to your solar power system. It provides you with somewhere to store the electricity you are not using and lets you use this electricity when the solar panels are not producing any power. In effect, it allows you to go completely off-grid. Alternatively, it can simply be a useful backup when you are having solar panel repairs undertaken.



It should be noted that the standard solar panel system uses a transformer to change the DC from your solar panels into AC that can be used by your home. Having solar batteries means installing a smart controller. It sends the power needed to the transformer for the home. Excess power is sent straight to the batteries in the form of DC. It is then pulled from the batteries by the smart controller when there is not enough power from the sun. At this stage, the controller sends the power through the transformer to turn it into AC. If you are connected to the grid you can charge the batteries during the off-peak periods from your main electrical supply.

Solar Batteries - solar panels

Are They Worthwhile?

Solar batteries do increase the cost of your system. On average you can expect a charge of $400 per kilowatt. As the average house will need between 10-15 kilowatts you will be looking at $4,000-$6,000 for the batteries. It is worth noting you can start smaller and connect extra batteries to the system as your budget allows. This is a significant investment but the battery systems are expected to last around 20-30 years, making them a reasonable investment. The good news is that the price of these solar batteries is likely to decline in the coming years. This is because car manufacturers are recycling used electric car batteries to make solar batteries.

The real question of whether this is a worthwhile investment will come down to cost. You will need to look at how much you currently spend on electricity from the grid. This will also give you a kilowatt usage figure which can help you to work out how big the batteries need to be to replace the grid power. If you spend more on power from the grid over ten years than it would cost you to install the solar batteries then you are onto a winner and it is worth making the investment. Don’t forget, to get the most from your batteries don’t plug everything in at the same time. Smaller demands mean the batteries will last for longer.