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How To Buy The Best Solar Battery

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How To Buy The Best Solar Battery For Your Home

We can all agree how much solar batteries have grown in the past few years. It’s safe to say they have a very bright future ahead, and their growth is not slowing down. Because they provide so many benefits, homeowners can’t get enough of them.

Their popularity in Australia has skyrocketed over the past 5 years. 

Did you know that Australian’s contribute to 30% of the global solar battery demand… That’s a lot. However, it might come as a struggle for some to understand which solar battery is best for your home. 

This is because there are so many different factors that need to be considered. Quite frankly, it gets confusing when companies are telling you that one solar battery is the best, but another is saying a different one is better. 

Having helped thousands of homeowners choose the right solar batteries across Melbourne, Brisbane and Adelaide it’s about time I share my hand-on experience with the rest of Australia, right? 

Ok, well let’s not waste any more time. Let’s go through the stages that you need to understand before you buy the best solar battery for your home. 

After this, you will be an expert in buying solar batteries, you can even help your neighbor choose! 

P.S If you haven’t already got a solar panel system, then check out my guide on how to buy the best solar panels for your home here.

Table Of Contents

What Are Solar Battery Storage Solutions?

In the most simple terms; solar batteries are designed to store any power that you generate from your solar panels. 

When this power is stored in your battery you have the freedom to use it whenever you want. This includes at night, when your solar panels are asleep and not producing any energy. Let’s also not forget that you can power anything electrical in your home, at any time (day or night).

Since most homeowners will only use electricity from the grid at night, solar batteries seem like a profitable investment. Especially for those who have invested in electric cars. Having the option to charge your car overnight can really help. 

Well, I think we can all agree that the idea of breaking up with your energy retailer doesn’t sound that bad. Having freedom of when you use your own energy, plus using less from the grid. What about no more sneaky price electricity increases! This is exactly what a solar battery storage solution can give you. 

How Can They Benefit You In 2021?

There are so many different ways that solar batteries can benefit you in 2021. This is the main reason why they are so popular. I mean, if they didn’t offer your home value, no one would buy them.

Return on investment

Most importantly, solar batteries offer you a very safe and secure investment. Unless something major happens you are guaranteed to make your money back from solar batteries.

This is because they reduce the amount you pay for your energy bills. The savings you earn each month can help pay off the system. Once it’s paid off, you are making money.

Backup power for blackouts

That’s right. Solar batteries will give you backup power in case of a power cut or blackout. This means no more annoying power shortages, warm food or being bored during an emergency. By the time the sun rises your battery will be getting charged again as well. For some homeowners this is a necessity.

Virtual power plant ready

Solar batteries can allow you to become virtual power plant ready. Now, a virtual power plant works by a community of homeowners all sharing their renewable energy with each other. Solar power gets shared with everyone and solar batteries provide the energy needed at night.

This can help the entire world by reducing fossil fuels and greenhouse gasses. It will also massively reduce your energy bills.

Energy independence

You can also gain independence by having control over your energy. You can now access when you use it and where it goes. Like I said, you can still sell it back to the grid, store it or just self consume it from your panels. It’s easy.

How To Choose The Right Battery For Your Home

So these are the questions that we go through in our personalised consultations with customers. Here you should really be able to work out which solar battery will be best suited for your home, and your requirements

How big is your budget?

Obviously you will need to understand if you can afford a high-end, bigger battery or a smaller, good budget one. On average, you can pay around $1000 per kWh for a solar battery. The bigger it is, the more expensive. Additionally, the location and difficulty of your installation may affect the price. 

For my recommendation, those who have a small budget should look towards 8kWh solar batteries. With a bigger budget you can look at 10kWh or above. One really affordable solar battery is the SolaX Triple Power 6.3kWh. This would suit homeowners that don’t use much energy.

If you have a bigger home using more energy, a Tesla powerwall 2 is one of the best batteries on the market right now. I can highly recommend it, and you can see our full review on the powerwall here

But yeah, working out your budget is the first step. You will also need to consider the amount of energy that you use as well. This may change your budget, because if you use a lot of energy then you may need a bigger solar battery.

how much budget do you have to spend on a solar battery

How much energy can you produce?

Finding out how much energy you can produce is extremely important. This is because you will need to be able to fully charge your battery to make it a worthwhile investment. Not only this, but because some energy is lost when it gets stored, you will need to actually cover that loss with more energy. 

This means you will need to be able to produce more than the battery capacity to store it. It’s something that you need to consider and not everyone will actually tell you about. It’s important.

For example, Tesla powerwall has a 90% round trip efficiency, (this is really good) which means that 10% of energy is lost when stored and reused. On average you may need more like 15.2kw to fully charge the 13.5kw battery. 

Going back, you need to make sure that you are able to produce enough energy. If not, then a solar battery might not be the best investment for you.

How long will you need your battery to last?

This could also mean, how much will you need your battery to do? Are you in a remote location that suffers from frequent power cuts? 

If you are going to need your battery to last for a couple of days after being fully charged, you’re going to need a big battery. Again a powerwall will work really well. Some others are the LG Chem 13 and Sonnen 15kw battery. 

Most homeowners will only really need their battery to last overnight. Once the sun rises it can be charged again. However, others who live in rural locations may need it to last longer. 

It really depends on why you are getting the battery. If it’s just for reducing your bills further, then a smaller battery would be good, around 10kw. However, if you are needing it as a power supply then it’s definitely worth investing in a big battery to last longer. 

why do you need a solar battery?

Where Should You Place Your Solar Battery?

I would definitely say this is the biggest challenge we find as solar battery installers. There are so many different requirements to meet making it difficult to find the most suitable place for your battery. 

The best and most common place to install solar batteries are in your garage, or on an external wall outside your home. They also require the installation to have enough space between your battery and any windows, doors or appliances (e.g. air con, hot water).

Wall mounted solar batteries must be installed on a wall that is fireproof and cannot catch alight. You can overcome this by installing a fireproof sheet on the back before the battery. The best walls for fire resistance are cement, brick or concrete. 

If you are installing your battery in your garage, it’s best to keep it covered with a bollard or protection to stop any cars from accidentally bumping it when parking. 

Here are a list of places solar batteries cannot be installed:
  • Habitable rooms e.g. bedroom, living room 
  • Direct sunlight 
  • Under stairways 
  • Ceiling area 
  • Evacuation routes 

How To Compare Solar Batteries

When you are ready to start looking in the market for the right solar battery, you will need to know what’s important to compare. These will be the key selling points of the battery, and the most important areas to look for. I’ve broken them down into sections for you. 

Warranties & bankability

Warranties are particularly important when you are investing so much money into a product. You need some security that it’s going to work for a long period of time or else you will get a replacement.  

Really, the minimum warranty you should be going with on a solar battery is 10 years. Now, it might even live longer than that. However, this is the industry standard right now, anything less may lose you money. 

The likes of Tesla, Sonnen and LG all offer 10 years or more. Additionally, LG and Tesla have some extremely good reputations as well. 

Both companies have other areas of businesses than solar batteries. Tesla has cars and LG has electronics. This can give you confidence that if something were to ever happen in the solar battery industry, they would still have money from their other businesses. 

You could still claim your warranty and get your money back/replacement. It’s good to go with brands that have a strong bankability and reputation when investing in solar products (same for panels too).

Capacity & power

This is the amount of energy that your solar battery can store, and the amount of energy it can provide at one given moment. Ideally the best solar batteries have a high capacity and high power rating

However, you may find a battery with a high capacity and low power rating, this means that its charge will last for a long time. For some people this might be what they are looking for.

On the other hand, a solar battery with low capacity and high power could run your entire home but only for a short time. 

I suppose if you are only needing a battery to power your home throughout the night, its wise to maybe look for one with a higher power rating. Although if you’re looking for continuous, long lasting power then a low power rating is good.

Going back to Tesla’s powerwall and the LG chem, both of these are in the middle really, making them a suitable battery for most homeowners. The powerwall offers 5kW continuous power output, and 7kW peak power output.

Round trip efficiency

As I mentioned before, the round trip efficiency is where some energy is lost in the process of storing and releasing energy. 

Using the powerwall as an example; It happens when energy is converted from AC into DC by the powerwall to get stored. When it is ready to get used again it is converted back into AC using the built in inverter. 

However during this process some energy is lost, or wasted. Unfortunately you cannot get this energy back which is why having a high round trip efficiency % is really important. If you had a solar battery with 50% round trip efficiency then half of your energy is being wasted. 

If it takes 8kWh to charge your battery you would actually need to produce 16kWh to fully charge it and cover the lost/wasted energy. Although, from what I can see most solar batteries on the market have a round trip efficiency of over 75%

Grid Connection Vs Off-grid

So this question gets asked a lot. I can obviously see the appeal for those people who are wanting to go completely off grid. I mean, you won’t get charged anything by your energy provider. 

However, I think it’s an expensive mistake. For the amount of money it would cost you to completely sever your grid connection, it’s not worth it. 

I mean, what also happens to your feed-in tariffs and if you want to sell any excess energy back to the grid? Let’s not forget in case of an emergency and you need to pull a small amount from the grid.

It’s so much more wise to keep your connection. You would probably need a small diesel generator if you did want to do it. 

To be honest, a solar battery will allow you to go virtually off grid anyway. It’s best to just keep the hybrid. The only time you will pull energy from the grid is when your home is using a lot of power. This is probably the best way to go in my opinion.

What Solar Battery Rebates Are Available?


The battery rebate program offers homeowners in any area of VIC a $4,174 deduction off the cost of a battery. This has been decreased from $4,838 which it once was. However, this only used to be available for homeowners in eligible postcodes. Since November 2020 this has been made available for anyone who lives in Victoria. 

Please remember that you will only be able to apply for the battery rebate or the solar panel rebate. You cannot claim both. 

South Australia 

The home battery scheme in SA offers homeowners access to a state government subsidy of up to $6000! This is a really good scheme, no wonder batteries are so popular in SA. For more information please visit their website.


Buying a solar battery can be difficult, but if you use this guide to help you it should make things easier. Just try to remember why you are buying a solar battery as this should help you decide. 

To be honest, there aren’t many bad solar batteries on the market right now, so any of them you go for should do the trick. Try to compare them using my guide above and it should help you get the perfect one for your home. 

If you are stuck between buying one, just remember that time is money. You could be saving a significant amount of money right now, and it could be costing you a lot by waiting. 

There is no harm in getting a quote and seeing what your options are! 

Let me know your thoughts in the comments below 🙂

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Written By:

Luke Cove
Managing Director
Lightning Solar & Electrical

local brisbane cec installer

2 thoughts on “How To Buy The Best Solar Battery”

  1. Thanks Luke,
    Your article was very helpful and seemingly impartial.

    I have 2 solar panel arrays which are aligned so that one gets most exposure in the morning and the other in the afternoon. By 11.00 am – 2.00pm, in summer, both are generating quite a bit. So much so, that together, they’ll generate well over 5kw, causing the newer Growatt inverter to shut down if I’m not using the power. The older Sunnyboy does not have a shutdown regulator.

    I’m interested in a large Tesla battery, (or x 2), which should cover all my evening needs. However, I also have in- slab heating which I currently use only in winter, usually only at night for around 7 hours, and is on Controlled Load 2. This pulls 6kw/ hour. I don’t expect that even 2 batteries would be able to provide for all of this. But because this system consists of 5 separate elements, I can easily separate them, and have some remain on CL2, and some fed by the battery, or batteries.

    Given all of this, can you give me any advice on what could be my best options.

    Many thanks. Gino.

    1. Hey Gino,

      You’re correct, if you are generating over 5kW and its getting wasted by the cap on your inverter it would be a wise idea to start looking at investing in a solar battery to store that wasted power. There are a few options for you to look into regarding isolating your elements, I think it would be hard for me to make an assumption without asking for some extra details.

      Would it be possible if you dropped me an email through to [email protected] and we can go through this one together?


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