Solar energy is a rapidly expanding industry and thanks to innovative leaps in battery storage technology in recent years, it’s now more viable than ever. For those who aren’t yet in the loop, a solar battery is essentially just that – a battery that stores power generated by your solar panels. In the past, solar energy that was not immediately used by your household would be transferred into the energy grid, however if your home has a storage battery installed, this energy can now be stored for use later on.
Analysts are predicting that half of all households in Australia will adopt a solar storage system in the next 10 years, so it’s worth knowing what’s out there. We take a look at what storage systems are available or soon to be available on the Australian market. Here is a list of retailers, followed by a closer look at each brand.
Solar battery brands quick guide
Samsung’s SDI all-in-one battery storage device was one of the first to hit the Australian market. It combines a solar/battery inverter and a lithium-ion battery with a modest 3.6kWh capacity.
Origin Energy is trialing the 3.6kWh Samsung SDI battery storage unit for its customers in some areas. Samsung has said it is working on larger batteries, including 6.2kWh and 10kWh models, however there is unfortunately no pricing information available as of yet.
- Web portal and mobile app monitoring system and control features
- Two-year product warranty and seven-year performance warranty
AllGrid Energy is a Brisbane-based energy research company. In August 2015, it launched its solar battery, the 10kWh WattGrid.
The WattGrid solar battery is not your conventional battery and instead holds its charge in tubes of a lead-acid gel variant. While this is alleged to improve efficiency, it makes the battery less ideal for outdoors. The battery has four modes: Solar, battery, grid backup and time of use.
The time of use mode lets it draw electricity from the grid at off-peak periods, while the backup mode will ensure there remains a reserve of backup energy in the event of blackouts and will prioritise certain appliances like fridges. On its release, the battery system retailed for $11,999 (not including installation).
- Real-time monitoring software
- Four modes to optimise electricity storage and usage
- Not ideal to install outside
Redflow currently offers Zinc Bromide batteries ranging in sizes from 8kWh to 11kWh, specialised for commercial use. According to the executive chair of Redflow, these batteries last 10 years and stand out in the market in that they can discharge 100% of their stored energy, unlike most other solar batteries.
In the middle of 2016, Redflow released its first residential storage solution, a 10kWh battery called the Zcell. The company is currently taking expressions of interests for these units, but has not yet disclosed a price information
- Liquid battery means it can switch off for long periods without losing power
- Can safely discharge 100% of electricity
- No touch interface or in-built monitoring software as of yet
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The Powerwall is a sleek lithium-ion solar battery produced by Tesla – a global leader in technology innovation. It hit Australian shores in 2016 and has already begun to help Aussies slash their power bill.
The Tesla Powerwall has a capacity of 6.4kWh and has an efficiency rating of 92.5%. The Powerwall has a life expectancy of 15 years and comes with a 10-year performance warranty.
While the Powerwall looks great, it doesn’t include a solar inverter or an in-built energy management system, so before purchasing a Powerwall you will need to factor in the costs of these components
Most Australian retailers that offer the Powerwall do so as part of a package deal, and do not offer it as a standalone product as of yet. If it is retailed individually, the device itself – excluding inverters and installation – is expected to cost around $7,000.
- Can stack to increase maximum storage capacity
- Smaller in weight and size than most lithium solar batteries
- Simple installation and low maintenance compared with many other storage units.
- 10-year performance warranty and 15-year life expectancy
Global tech giant Panasonic is also getting in on the solar battery trend. It currently produces the LJ-SK84A residential storage battery system. While its name isn’t the best on this list, it certainly contends as one of the most practical residential storage batteries.
Panasonic’s solar storage unit is an 8kWh lithium-ion battery with 93% efficiency, though it is only currently available on trial through ActewAGL, Ergon Energy and Red Energy. These trials so far have reportedly produced impressive results with Red Energy taking on Panasonic as its sole provider of home batteries.
Panasonic’s storage battery system is programmable to charge and discharge when the consumer wants, and includes a backup feature in case of blackouts.
- Programmable features
- Cannot be chained to increase storage capacity
- Not designed to go ‘off-grid’
Sunverge Energy has pioneered the development of a storage unit called the Solar Integration System or SIS. This storage unit comes in 7.7kWh, 11.6kWh, 15.5 kWh and 19.4kWh, with all necessary inverters and monitoring hardware in built to the system.
Sunverge claims that its energy management system is compatible with most leading household hardware systems and provides more real time usage data than any other system. Again, like most solar batteries, Sunverge’s SIS is programmable to optimise battery usage during peak demand periods, and includes a backup feature in case of blackouts.
The Sunverge SIS can be purchased in three sizes through AGL. Its 7.7kWh system can be purchased for $9,990, while the 11.6kWh and the 19.4 kWh can be purchased for $14,990 and $19,990 respectively.
- Programmable: Time of use optimisation, backup power and solar power prioritisation
- Web portal and mobile app energy management system compatible with most systems
- Most necessary components (including inverters) are built in to SIS system
The Enphase storage system brings something quite unique to the table with its modular lithium-ion phosphate batteries. Each battery only has a capacity of 1.2kWh, however they’re designed to stack to give customers a completely customisable storage solution.
Enphase says its battery is the most affordable upfront and has the highest lifetime value than anything else currently on the market. It is also compatible with most solar systems, meaning there’s no need to upgrade to an expensive hybrid inverter.
RenewEconomy says that most solar retailers are pricing the Enphase Storage system with a single battery at around $1,900 to $3,000 including installation, with additional modular batteries costing around $1,000 per battery.
- One of the cheapest batteries to buy and install upfront
- Lower life expectancy (10 years) than most other batteries
- Modular design gives it capacity customisation
- In built monitoring options
ZEN Energy started with the launch of its ZEN Freedom Powerbank – large batteries in 20kWh and 40kWh sizes with backup diesel generators for off-grid application. The company then followed up with a range of residential grid-connected batteries with its ZEN Urban PowerBank, in sizes from 10kWh to 20kWh with prices ranging from $10,000 to $15,000.
In September 2016, ZEN Energy went even smaller, announcing a partnership with Sonnen batteries and Redbank Technologies to provide a range of batteries in sizes from 3.3kWh to 10kWh, with prices starting at $8,990.
- A range of battery sizes to suit both on and off-grid households
- Three-year battery warranty
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Fronius has traditionally specialised in PV inverter technology, however it now has its own battery range with capacities varying from 4.5kWh to 12kWh. Alternatively, Fronius also produces a battery module system. Each module stores 1.2kWh and the system can stack to create a storage system of any size to suit your needs.
Fronius says its batteries have short charging times, high depth of discharge, and an impressive life expectancy of 20 years. Unfortunately there is very little pricing information available online at this point in time.
- High efficiency and depth of discharge
- Inbuilt Fronius inverter so only compatible with certain solar systems
- One of the longest advertised life expectancies
Ecoult has produced a hybrid, long life lead-acid energy storage unit which Ecoult says is like nothing else out there. The storage unit labelled by Ecoult as the “UltraBattery” was launched in 2016 with a 5kWh capacity. Ecocult has also announced the development of an 11kWh battery which it expects will cost just below $20,000.
Ecoult claims the advantages of lead-acid batteries are that they are safe, recyclable and produce next to no emissions. Historically lead-acid batteries have been less ideal for rechargeable units however, with lithium-ion being the preferred alternative thanks to its slow diminishing characteristics. With that said, Ecoult says its battery lasts much longer than any other lead-acid battery and insist that the UltraBattery can rival its lithium-ion counterparts on every metric. At this stage there is little more information available.
LG Chem is the chemical battery division of global giant LG. It’s been in the solar storage unit market for a while and currently holds nearly half of Australia’s solar battery market share. LG Chem launched in Australia with its RESU Main pack with a capacity 6.4kWh, as well as its RESU expansion pack which adds additional capacity in increments of 3.2kWh. These are currently only retailed through Solar Juice with the main pack pricing around $7,000 excluding installation and inverters.
In late September 2016, LG is set to release two new batteries in Australia. The first is the RESU6.5 – a 6.5kWh lithium ion battery that is smaller and better designed for indoors than its 6.4kWh predecessor. The second is a 3.3kWh modular battery, which lets customers stack multiple batteries to customise storage capacity. There is currently no pricing information available for these new products.
- 15 to 20-year life expectancy, plus 10-year warranty
- Compact and lightweight batteries, great for indoor storage
- Range of battery sizes including modular systems to suit a range of storage capacity needs.
Aquion has produced a hybrid-ion saltwater storage unit which the company claims is environmentally friendly and safer than chemical batteries. Aquion’s flagship battery is its 48S battery which is a 2.2kWh modular battery that can be stacked to create a storage unit with a larger capacity.
Aquion doesn’t provide any price information on its batteries, however the company says that while its batteries are generally more expensive to purchase up front, they have a greater lifespan and lower maintenance cost than chemical batteries.
A major drawback of using saltwater in the Aquion batteries is that they have to be stored indoors and are not suitable for extreme climates where the battery may freeze of overheat.
- Modular customisable capacity
- No monitoring system included
- More expensive up front, though Aquion says it’s cheaper in the long term
- Only suitable for mild climates
The Imergy Energy Storage Platform (ESP) uses redox flow battery technology which the company claims is the most cost-effective and reliable energy storage solution available today. Imergy batteries claim a 100% depth of discharge while not losing any storage efficiency for thousands of cycles.
It’s flagship series of solar storage units are the ESP5’s which have a capacity range of 15kWh to 30kWh – ideal for businesses or large homes. Imergy also produces batteries of up to 1MWh for massive industrial application.
- Can be installed outdoors
- Remote monitoring and control features
- Minimum capacity is 15kWh – much larger than necessary for most households
- Safe and highly efficient flow technology
Magellan Power is a Western Australian company that has developed a residential solar storage unit called the Hybrid Energy Storage System or ‘HESS’. This unit comes in two sizes, 9.2kWh and 13.8kWh, and boasts an impressive output efficiency of 97%.
Magellan Power says the HESS has everything built in to the unit, so there is no need to purchase additional equipment, making installation quick and affordable. Being that it’s produced in Australia, Magellan Power also claim maintenance turnaround is swift as there is no need to import parts.
Finally, the HESS can be programmed to operate to charge at off-peak hours or discharge solar power during peak electricity periods to optomise electricity savings. It is also compatible with a monitoring app for mobile devices.
- Everything in-built for simple installation
- Inbuilt hybrid inverter means its compatible with most solar systems
- Mobile monitoring app
- 10 year performance warranty
Bosch is also trying its hand at solar battery storage with its BPT-S 5 Hybrid, marketed as an ‘intelligent energy management and storage solution in one’.
This lithium-ion storage system is available in five capacities from 4.4kWh up to 13.2kWh with a sleek design that Bosch is well known for. Bosch’s storage system is monitoring app compatible and has four pre-programmed modes, for morning, afternoon, evening and night to ensure it draws energy from the most cost effective source.
Information on Bosch’s battery is rather limited, however early lifespan testing has shown it can last 10,000 cycles without capacity deterioration – that works out to be a life expectancy of around 36 years according to Bosch, which is considerably longer than anything else on this list. Bosch has not yet provided pricing information, but says that this is a quality product targeted at a premium market.
- Very high life expectancy
- Probably on the more expensive end of the spectrum
- Sleek and modern design
Australia’s massive solar battery market potential remains mostly untouched, meaning we can expect an even more solar battery retailers and storage unit brands to appear in coming years. This will in theory drive down prices and make solar storage an even more attractive prospect, so even if you don’t think a solar storage battery is right for you just now, keep your eye on the market in coming years.
Keep in mind that this list has possibly missed some solar battery retailers. However, we will be sure to update it as new brands hit our shores.