SOLAR BATTERIES BRISBANE

This is a small battery suited to a customer that just wants a bit of backup power in case of a blackout, or a customer who is conservative with evening power usage and wants to avoid the peak demand tariff. 5kWh is the smallest battery BYD offers. Anything smaller would be a token toy. This battery is a good entry level size from the Electric Vehicle company that started out as a battery maker in 1995. The battery can easily be upgraded when you have data from your Fronius monitoring, and a bit more cash in the bank.  

Ballpark Average Solar Production
30kW Summer, 18kW winter 

To future proof a little, you could easily install a 6kW inverter & 7.9kW of panels to add 20 percent more production. 

Battery capacity
Usable storage = 5.1 kWh
Fastest charge rate = 4.49kW.
Continuous discharge = 4.49kW (plenty for a smaller battery) 

If you use a conservative amount of power during the daytime (8kWH) you will still be able to fully charge this battery on a mid-winter’s day. Even for humble households, the battery will fully discharge most nights. That’s getting great use out of your solar battery and it will not affect your warranty. 

Savings
The 5.1kWh BYD Battery Box is warranted for 15410kWh of usage, or almost one cycle a day for 10 years. If you calculated your savings on a traditional Brisbane tariff this system would save you a maximum of $2200 in its warranty period. However, in 2022, Queensland is rapidly changing to “Demand tariffs” where you are penalised for using power between 4pm and 9pm. Using your stored solar power during that time could save you significantly more. More importantly, your first home will be closer to being independent of coal fired electricity and your lights and power will work in a blackout. 

Blackout
You’ll want to decide if you are going to set a “reserve” limit on the battery. If you set a 2kW reserve, then you will be guaranteed of at least 2kW in a blackout. However, then your solar battery will only have 3.1kWh to charge and discharge each day. 

Max discharge during a blackout is a huge 4.49kW. However, to prevent the solar battery from discharging too quickly during a blackout, it may be wise to have just one light circuit and the kitchen power points only. 

Upgradeable Battery
At any time, you can easily add one more battery module to make your BYD solar battery 7.7kWh. This can be done now, or later. 

You can then add a second or third stack of batteries to give you 15.4kWh or 23.1kW of storage. Each stack will require its own battery management unit. If you plan on upgrading to more than 7.7kWh of solar storage, you may be better off starting out with our next package, the more easily expandable 11kWh battery. 

The 11kWh BYD battery uses a lower battery module voltage than the 5kWh battery, allowing you to stack more modules in one stack. This package is a large storage system on a smaller solar system. It would be great for the couple who is at work by day and runs the air conditioner by night. If you are uncertain about your energy consumption patterns, we’d recommend installing solar first, and using the Fronius monitoring tool, so we do not unnecessarily oversize your battery. It is fine to undersize with BYD, as it can be retrospectively upgraded in 2.5kWh increments. If you happen to oversize the battery, you can just set your blackout “reserve limit” higher.  

BYD is a company that Warren Buffet bet big on in 2008. It hasn’t let him down. 

Ballpark Average Solar Production
36kW summer, 22kWh Winter 

Battery capacity
Usable energy = 11kWh
Fastest charge rate = 4.49kW
Continuous discharge = 4.49kW (just a tad less than a Tesla Powerwall) 

Savings
It is warranted for 34150 kWh of usage. If you calculated savings on Brisbane’s historical tariffs the 11kWh BYD battery would save you a maximum of around $4800 in its warranty period. However, Queensland is rapidly changing to “Demand Tariffs”, where you are penalised for drawing power in the evening. A correctly sized battery will protect you from these demand tariffs and potentially save you a lot more. 

If you chose a 6kW inverter, you are much less likely to waste energy by “export limiting”. More of your solar can be harvested, saving you a little bit more money. But solar batteries are less about savings & more about energy independence – and electricity stability.
 

Blackout
If your main aim is to have solar storage for a blackout, you may want us to set your battery to discharge to no more than 2kWh in normal operation.  While this will ensure you always have some reserve power in a blackout, it will naturally limit the normal nighttime battery capacity. It’s a tradeoff. The chances are – your battery will not be completely flat when a blackout occurs anyway. 

Max discharge rate is a healthy 4.49kW total, and a max of 3.68kW per phase. A conservative Brisbane couple could potentially back up their whole house with this – including your hot water. You may just want to manually turn off your hot water and air conditioning during a blackout if your battery charge gets too low. 
 

Upgradeable
This solar storage battery can easily be upgraded to 13.8kWh, 16.6kWh, 19.3kWh or even 22.1 kWh. You could also install a second stack of solar batteries, but that wouldn’t make much sense with a smaller solar system. Maybe you should plan ahead for a baby. 

This BYD solar battery Brisbane system allows for a healthy 7.9kW solar system and a decent sized battery. With a three-phase home, you will want the Fronius & BYD option over any other for the reasons explained below. If you have a small family household with some daytime usage, a 7.9kW solar system should be able to charge a 10.2 kWh battery most of the year-round. It may be wise to install solar before the battery, so we can use your Fronius data to ensure we don’t oversize the battery. 

Ballpark Average Solar Production
36kW summer, 22kWh Winter 

BYD Battery Statistics
Usable energy = 10.2kWh
Fastest charging rate = 6kW
Continuous discharge = 6kW or 3.68kW/phase 

Savings
The BYD Battery Box is warranted for 30820 kWh of usage which in the past would have worked out as a maximum saving of $4300 in its warranty period. However, with Queensland’s new “Demand Tariffs,” you are charged a higher rate for using power in the evenings. If you eliminate your evening load with a battery, your saving could be significantly more than they would be otherwise. Nevertheless, batteries are still mainly about protecting yourself from future energy hikes, being mostly independent of the grid, and having power in a blackout.
 

Blackout
The advantage of Fronius & BYD on three-phase is a no brainer. If you have a blackout during the day, your solar panels will keep charging the battery. You would think you can take this for granted – but it does not work that way with the majority of 3 phase battery solutions.  

Additionally, during a blackout you will be able to supply a three-phase load such as an air conditioner. That would work just fine during a hot summer’s day while your solar is continually topping up your battery for nighttime use. 

If you are concerned about having power in a blackout on a stormy day, you may want us to set your battery to discharge no further than 2kWh. This will ensure you always have some reserve power in a blackout, but it will limit your discharge capability during normal operation. 

Maximum discharge in a blackout is 6 kW over 3 phases. However, each phase is limited to 3.68kW. While this won’t affect your savings while connected to the grid, you won’t be able to go crazy with hot water and air-conditioning on the same phase. It may be safer to leave your hot water off backup. 

Upgradeable
To upgrade this battery, you would need to buy another battery charging module (BMS). You could upgrade to 15.3kWh (by splitting the first stack) or to 20.2kWh (by adding a completely new stack.)  

However, if you wanted the option of upgrading, you may be better off starting with the 11kWh battery. And if roof space permits, you might want to consider a second or third kid. 

This BYD solar battery Brisbane system allows for a three-phase family sized solar system and a battery that will cover most of your nighttime load. With your pool running during the day, and kids home at 3pm and school holidays, you will use a significant amount of solar during the day. The larger 13.3kW solar system may be needed to ensure your battery gets charged each day.  

As I’ll explain below, the three phase Gen24 / BYD combo has significant advantages over most other battery systems.
 

Ballpark Average Solar Production
60kW summer, 36kWh Winter
 

Battery Capability
Usable energy = 13.8 kWh (bigger than the Tesla Powerwall)
Fastest charging rate = 5.63kW (faster than the Tesla Powerwall)
Continuous discharge = 5.63kW (higher than the Tesla Powerwall). 

Savings
It is warranted for 42690kWh of usage. If you worked out your savings on the old Brisbane and surrounds tariff structure this battery would save you around $6000 in its warranty period. However, South East Qld is changing to a demand tariff structure where you are penalised for using grid power in the evening. Depending on the energy plan you choose, and your usage patterns, a battery can save you significantly more when you cook dinner for the kids using your stored solar power. More importantly, you can say goodbye to future blackouts. 

Blackout
The advantage of the Symo Gen24 is your panels will keep charging the solar battery in a blackout. Most other 3 phase inverter + battery solutions (e.g: Tesla Powerwall) will inconveniently disengage the solar panels when you have lost grid power. 

Max discharge in a blackout is a healthy 5.63kW over three phases and 3.68kW maximum per phase. Assuming you are sensible in a blackout, you could potentially back up your whole house. You may just need to downsize any large 3.6kW hot water elements. Whole house backup is not recommended with other inverters (eg Sungrow), because you could overload the inverter while connected to the grid. 

The Fronius Gen24 inverter can also uniquely supply 3-phase power in a blackout – but with a 13.8kWh battery, and the limited 5.63kW discharge rate, you wouldn’t want to run your ducted air-conditioning for extended periods. – unless it was a sunny Brisbane day.

If you are concerned about being self-sufficient in a blackout during stormy weather, you can always upgrade to another solar storage module down the track and set a minimum reserve capacity for blackouts. 

Upgradeable
This BYD solar battery is easily upgradable to 13.8, 16.6, 19.3 or 22.1kWh by simply adding extra battery modules. This will also significantly increase your discharge rate. You can go even higher by adding a second or third stack of batteries, but if you do that, you’d probably want more solar too. 

This BYD solar battery Brisbane system is for a three-phase large family solar system with a battery that won’t quite cover an average summer’s night. The Solar is maxed out, and depending on seasonal household consumption, it may still struggle to fully charge your solar storage battery regularly in wintertime. Any load profile is hard to guestimate. Instead of installing a 22.1kWh BYD battery on the same day as your solar, I’d suggest you install an 11kWh battery, and wait 12 months for your Fronius monitoring data.
 

Ballpark Average Solar Production
90kW Summer, 54kW winter
 

Battery Capability
Usable energy = 22.1 kWh
Fastest charging rate I = 9kW
Continuous discharge = 9kW (3.68kW/phase) 

Savings
The 22.1kWh BYD Battery box is warranted for 68310 kWh of usage. If you worked out your savings on the old Brisbane tariff structure this battery would save you around $9500 in its warranty period. However, depending on the new Demand energy plan you choose, a battery can save you significantly more because you won’t need to rely on the grid at peak times. More importantly, you’ll be less affected by blackouts. 

BYD in a Blackout
One reason I recommend the Fronius Symo Gen24 is because your panels will keep charging the solar battery in a blackout. Believe it or not, most other 3 phase inverter + battery solutions are useless for an extended blackout, because they can’t keep charging your battery from your solar panels when grid power is lost. (e.g: Tesla Powerwall) 

The maximum discharge with this system in a blackout is a healthy 9kW over three phases and 3.68kW maximum per phase. Unlike the Sungrow RT Hybrid inverter, this Fronius/BYD combo could backup a large house. We would just need to be careful of balancing large hot water systems for off grid mode, and you’d need to use common sense about the solar storage battery charge levels. 

The Fronius Gen24 inverter can also supply 3 phase power such as ducted aircon in a blackout – and with a 21kWh battery, and a 9kW discharge rate, you could get away with it if you were not running other heavy loads at the same time. 

Upgradeable
To upgrade this solar battery, you would need to add another BMU (battery management unit) but you could increase the solar storage in 5.5kwh increments by adding old batteries with the new stack. This would also increase your charge and discharge rate to 10kW. But why not go the whole hog – and be prepared for the worst! 

If you are a serious prepper, you would not purchase such a large battery system without 6 to 12 months of monitoring with solar installed. When installed, you would still want to keep around 20 kWh of this battery in reserve for a blackout or WWIII. Not fully discharging your battery would also make it much more likely to charge your battery back to a healthy state on an overcast day. 

If you are the energy-guzzling family; you may not always have enough energy to fully charge this solar battery. If the solar storage is not fully charging at least once a week, we’d suggest increasing the reserve power limit, so your battery does not degrade too quickly. 

As a prepper, you will want proven reliability. BYD makes the world’s largest electric buses. They’ll work just fine powering your home.
 

Ballpark Average Solar Production
90kW Summer, 54kW winter 

Battery Capability
Usable energy = 57.9 kWh
Fastest charging rate = 10kW
Continuous discharge = 10kW (3.68kW/phase) 

Savings
It is warranted for 179310 kWh of usage. If you calculated savings on a traditional 8-cent feed-in tariff this solar battery alone would save you around $25 000 in its warranty period. However, all Brisbane homes will soon be on a “Demand Tariff,” where you are penalised more for using power between 4pm and 9pm. This is when a battery can offer significantly higher savings while minimising your impact on the grid’s peak demand. More importantly, your family will be ready for the zombie apocalypse. 

Blackout
If you want a guarantee of power when that day comes, you will want to set a reserve power limit on your solar battery. However, assuming you have some sunshine, a battery and solar system this size should be able to keep you comfortable for many weeks without grid power. 

Max discharge rate in a blackout is a huge 10kW, or 3.68 kW per phase. The Fronius Gen24 inverter can supply 3 phase power in a blackout – so you will even be able to run three phase loads in a blackout – such as a bunker air filtration system. 

Unlike most 3 phase solar battery storage systems, your Gen24 inverter will keep charging the BYD battery in a blackout. Almost every other 3 phase battery solution cannot keep a 3-phase solar inverter online – so you wouldn’t last without grid power for more than a day. 

Upgradeable
Congratulations. At 57.9kW kW, you have realistically maxed out your BYD solar battery capacity.