Tesla Powerwall Battery

Battery Buying Made Simple: Your Expert Guide

Have you already invested in a residential solar panel system? Or are you a commercial solar customer looking for a way to store your generated energy by installing a solar battery array? 

We understand that purchasing a solar battery can seem like a daunting process, which is why we’ve created an expert buying guide to help you understand why a solar battery is an important part of any solar panel system and how to decide which size of battery is right for your solar panel installation.

Why Do You Need a Home Battery System?
Installing a solar battery as part of your solar panel installation could add as much as $10,000 to the estimated solar panel prices you’re likely to have seen from your local solar panel installers in Sydney or your local area. However, there are several advantages to absorbing this cost upfront, despite the price tag. 

Use Energy When The Sun Goes Down 

If you are a night owl or have a high electricity usage in the evenings, as many people do, then a solar battery might make all the difference for you. It would mean that you wouldn’t necessarily have to switch to a traditional form of electricity, and it could mean that you can become 100% energy-independent, depending on the size of your solar panel. 

You can also install more batteries periodically as your needs increase, likely for a lower cost.

Time of Use Tariff Benefits 

Time of Use (ToU) Tariffs apply different prices to electricity at different times of the day. These are divided into Peak, Shoulder and Off-Peak times, calculated by demand on an electrical system. With a solar battery, you reduce the amount of ToU tariff placed on your electrical bill during peak electrical grid usage times, generally between 5 P.M. and 9 P.M. 

Having a solar battery combined with large enough (or multiple) panels, even smaller arrangements like a 5kw solar system will likely be able to power you through these peak times, reducing (or eliminating) the highest daily billing cycles on your electrical bill.

Battery Backups Make Power Outages A Breeze 

With a solar battery backup system, you can stay powered even if a storm knocks out electrical power. Using a solar panel and solar battery system means that you don’t have to worry about making sure you have petrol in your generator or enough oil lamps and candles to signal a ship in the night.

What Type of Battery is Best? 

Three main types of batteries are used in solar solutions for electrical power. These are Lithium-ion, lead-acid, and flow batteries. Until 2015, lead-acid batteries (like your car battery) were the most common solar battery option in homes. Unfortunately, these were heavy and required dedicated rooms or outside spaces and a regular maintenance schedule to ensure no leaks. 

However, since 2015, Lithium-ion batteries have exploded in popularity due to their lightweight, low-maintenance nature. They also have an edge on lead-acid batteries in performance. Lithium-ion batteries output more power with a reduced discharge depth; essentially, they’re much more efficient than lead-acid. 

Flow technology is slowly emerging as the future of battery power, mostly due to its long-lasting lifespan. However, the disadvantage of flow batteries comes in their low-energy capacities at present, although as technology advances, this capacity will increase, potentially making them a more viable option for the future. 

However, currently, Lithium-ion batteries are your best option for any residential solar panel installation.

Marrying Your Solar Battery to Your Solar System 

When it comes to joining your new solar battery up with your existing solar panels and their hardware, you have two choices: direct current (DC) coupling and alternating current (AC) coupling. 

You’ll need to buy a solar inverter in either case, although AC coupling systems are easier to manage with a single inverter that pairs with any system. In contrast, the DC coupling method uses a single hybrid inverter, which is more expensive and system-specific. 

How Does a DC System Work? 

Direct current coupling systems convert energy collected from the hybrid inverter and transfer it to the battery for storage. When the battery is discharged, that energy travels through the inverter to the home or the grid. As there is no change in the current type, thanks to the hybrid inverter, DC solar panel systems lose less energy, making them more efficient than AC systems.

How Does an AC System Work?

Similarly, an AC system uses an additional battery inverter when energy is transferred into the battery, therefore creating another ‘stop’ on the road that the energy collected from your solar panels takes on its way to your home or the grid. 

This extra conversion of DC energy from your solar panel into AC energy via the inverter, then back into DC energy for battery storage purposes, tends to make the AC system less efficient than its DC counterpart. 

However, it is worth noting that AC systems will work with any solar panel setup, making them a more cost-effective option upfront, although these gains may be lost in energy efficiency as time goes on. 

Your electric service provider may also limit the number of kilowatts that can be moved into the grid at any one time. This is usually a limit of 10kw. However, they may also count the extra wattage generated by the extra inverter found in the AC unit towards that upper limit of 10 kilowatts. With DC coupling, the singular inverter bypasses the limit imposed by your service provider.

Big Batteries, Big Bills 

One drawback of households installing a large solar battery system and coupling it with their solar panels is the upfront cost, as mentioned above, which can be as high as $10,000 or higher. To get the most ‘free’ electricity (that is stored energy) out of your solar battery, those batteries need to be quite large, and the bigger the battery needed to accomplish those hours of ‘free’ electricity, the higher the cost to source and install will be. 

However, this should not deter you from installing a solar battery, or several into your solar panel system. Solar battery systems can pay for themselves in time, depending on how much ‘free’ energy you use and when you use it. If you’re coupling battery use with off-peak hours of Time Use Tariffs, you may see more savings over a shorter period.

Final Thoughts 

Solar battery technology has come a long way since 2015, when Lithium-ion technology really started to become more popular and improved its sizing and efficiency options, mostly thanks to Tesla’s innovations. Solar batteries represented a huge 55% market growth in 2022, with Flow battery technology representing a 22% growth globally. Solar energy and battery storage is becoming an Australian (and global) phenomenon that is much more accessible to the masses and, therefore, cheaper than ever before.

The federal and state governments of Australia recognise that this technology is heading in the right direction and have offered funding to businesses and individuals seeking to put solar panels on their roofs, both in the form of reimbursement for electricity generated into the grid and in cash upfront to help cover costs of solar panel installation. Get ahead of the game and use the government’s (free!) money to help you install your first solar panel and start your battery bank. Contact Bare Energy today to get started!

Scroll to Top