Besides the Powerwall, what solar batteries should you consider?
Home solar batteries become more popular every year - and for good reason. Solar batteries continue to get cheaper, and with widespread power blackouts becoming more common, people want to make sure they have access to reliable electricity.
The Tesla Powerwall has been the solar battery of choice for most homeowners, based on brand recognition and ease of use. But limited availability means getting your hands on one could take a while.
Some of the most popular Tesla Powerwall alternatives are the Enphase IQ battery, the sonnenCore, Generac PWRcell, LG Energy’s RESU Prime, and the Panasonic EverVolt. In fact, many solar installers actually prefer these brands over the Tesla Powerwall.
Below is a rundown of the top solar batteries that are available for sale and up to the task of providing backup power for your home. We’ll cover each of their strengths and weaknesses and how they compare to the Tesla Powerwall.
The Tesla Powerwall
The Tesla Powerwall is designed to be easy to use and to be a sleek addition to your home. Image coursey of Tesla, Inc.
Since the release of the first Powerwall in 2015, Elon Musk’s company Tesla has worked diligently on refining and improving its energy storage solutions. The current Powerwall+ comes with a 13.5 kWh usable capacity and is one of the most widely-installed battery backup for home use.
The Powerwall costs about $9,200 for the battery before installation costs. When you factor in installation, the price jumps to around $13,000. If you purchase a Powerwall with a Tesla solar panel or solar roof system, the price will be closer to $11,500.
It’s very simple to use, with an app that controls how and when energy flows to and from the battery. The Powerwall is designed to fade into the background of your life, doing its job and remaining ready for a power outage.
That simplicity can be a benefit and a drawback. The Powerwall battery is easy to use, but because it’s connected to your home via AC power, solar energy to be stored in the battery is converted from DC to AC first, meaning the battery is less efficient than one with a direct DC connection to a solar installation. In addition, the Powerwall comes only in one size. If you need just a little more energy than one can provide, you’ll need to pay for a whole second battery.
Another problem has to do with battery chemistry. Tesla is among the many battery manufacturers that use lithium nickel manganese cobalt (NMC) in its battery cathodes, while other manufacturers have chosen lithium ferro phosphate (LFP) chemistry. NMC batteries perform very well, but cobalt is toxic and can only be mined in specific places in the world, where it’s associated with a variety of health and safety issues. Additionally, NMC batteries operate at a higher temperature and are more associated with an increased risk of fires than LFP batteries. Tesla has hinted that it will switch to LFP for all its energy storage products, but that hasn’t happened yet.
Finally, remember that the Tesla Powerwall is popular, so wait times can be long. So, if you can’t wait for the Powerwall, what batteries can you get?
Enphase Energy IQ battery
The Enphase IQ 10 battery is a popular offering by installers. Image source: Enphase
Enphase Energy is one of the two largest manufacturers of solar inverters in the world, so it makes sense that the company recently introduced a battery that interfaces with your home using a special version of the company’s famous microinverters. The Enphase IQ Battery is an AC-coupled lithium iron phosphate (LFP) battery that comes in 3- and 10-kWh sizes that can be mixed and matched to create a larger battery bank.
In addition, IQ batteries can be connected to fossil fuel backup generators from popular companies like Kohler, Generac, and Cummins. This type of setup would provide a true off-grid experience when paired with solar panels, although it would eliminate the federal tax credit for the battery, given that it wouldn’t be charged exclusively from solar energy.
Pros of the Enphase IQ battery
- Enphase uses the safer LFP battery chemistry in the IQ battery
- The IQ battery has a built-in way to connect it to a fossil fuel backup generator for off-grid applications
- The IQ battery comes with a good warranty that promises 70% of capacity after 10 years or 4,000 cycles
Cons of the Enphase IQ battery
- The IQ has relatively low peak output, with a continuous output of just 3.84 kW
- The Enphase battery is limited to AC-coupled installations, although the company claims its microinverters are responsible for high round-trip efficiency
- The Enphase IQ battery doesn’t have the same modern look as the Tesla Powerwall
sonnenCore battery
The sonnenCore battery is sure to fulfill your energy storage needs. Image source: sonnen
German energy company sonnen has long focused its efforts on the production of solar batteries. Since 2017, sonnen has marketed its batteries in the United States through a network of installers.
The company previously only offered luxury solar battery solutions that exceeded the budget of most homeowners. In 2020, sonnen decided to take a stab at the mainstream residential market with the release of their newest battery, the sonnenCore.
The all-in-one sonnenCore battery storage system is a 10 kWh lithium iron phosphate battery that costs $9,500 before installation. This is substantially cheaper than their sonnenEco or EcoLinx models that could cost over $30,000 to install.
Pros of the sonnenCore solar battery
The sonnenCore battery melds together solar energy with features befitting even the most technologically advanced smart home, while still keeping it at a reasonable price.
Because of the company’s commitment to advancing technologies, the battery has many useful features that should be considered when looking at battery backup systems.
Some features of the sonnenCore solar battery include:
- sonnen's smart system allows owners to manage where energy is being sent
- The sonnenCore has a variety of operating modes so you can get exactly what you want out of your battery
- The sonnenCore is an LFP battery, meaning it is safer and less toxic than NMC batteries
- sonnen offers a 10-year warranty that ensures the battery will maintain up to 70% of its storage capacity over a 10-year lifespan
Cons of the sonnenCore solar battery
- While it is cheaper than sonnen’s other batteries, it still costs a little more than other solar batteries on the market
- The battery only comes in one size, so homes with high power usage may need to install more than one
- The sonnenCore is not rated for outdoor installation, so it must be installed indoors
What type of home is the sonnenCore solar battery best for?
The sonnenCore battery is best for homeowners looking for advanced features like Time-of-Use load shifting and those who are interested in being able to track and control where their power is going. It’s also ideal for homeowners who expect to discharge their battery regularly, as it has one of the best warranties and throughput guarantees.
The sonnenCore can also bring you peace of mind, as its chemistry makes it safer and easy to recycle.
Generac PWRcell
Generac knows backup power, and their modular battery gives homeowners power over their storage option. Image source: Generac
Generac has long been one of the top companies making home generators that help people survive during a power outage, so it’s natural that they have added home batteries to their lineup. The story of the PWRcell home battery starts with an acquisition. Rather than spend years developing an in-house solution, Generac bought Pika Energy, a successful manufacturer of home storage systems, and adapted its PWRcell for use in home systems.
Generac saw a way to integrate its own home energy management technology with the solar storage system. The company now sells its solar battery alongside Smart Management Modules (SMMs) to provide true whole-home backup, and plans future integration with additional smart circuits and a backup generator for true off-grid operation.
Our estimates show the PWRcell battery will add between $10,000 to $18,000 to the cost of a solar installation, depending on the number of battery modules included in the system. Like other solar batteries, that cost before any reduction from the federal tax credit, which can reduce the cost by 30%.
Pros of the Generac PWRcell
- The battery is truly modular, with 3 kWh battery packs that can create a system sized between 9 and 18 kWh in a single cabinet, or up to 36 kWh in two cabinets
- Additional battery modules can be added if your energy needs change in the future
- The PWRcell is a DC-coupled battery that comes with its own set of solar power optimizers, making it very efficient
- Generac’s SMMs turn off certain circuits to allow the PWRcell to start up big appliances like air conditioners and microwaves, meaning you can theoretically back up more circuits than with the Powerwall
- Future integration with even more smart circuit tech and a specially-designed natural gas/LP generator will allow homes to go completely off-grid with PWRcell.
Cons of the Generac PWRcell
- Because it’s not just a plug-and-play battery, PWRcell is basically impossible to retrofit with an existing solar system
- The PWRcell uses the same NMC battery chemistry as Powerwall
- The PWRcell is more expensive than some other batteries in this list
What type of home is the PWRcell right for?
If you haven’t yet installed solar panels on your home, and you’re in the market for a solar + storage solution, the Generac PWRcell system might be right for you. It’s a smart solution to home backup, and its modular design means you can size the system to your needs and even have room to inexpensively add more storage if those needs change. If you live in an area that is prone to power outages or want to go truly off-grid in the future, the PWRcell is a great way to power your home.
LG Energy Solution RESU Prime
The RESU Prime is a solid option for homeowners looking for more storage than the Powerwall, but it doesn’t come with the same bells and whistles. Image source: PR Newswire
The LG Energy Solution RESU battery is a lithium-ion battery that captures solar energy and stores it for later use in residential settings. In 2021, Energy Solution (formerly LG Chem) introduced new higher-capacity RESU Prime batteries in order to answer the needs of the marketplace affected by power outages and to more directly compete with Tesla.
The RESU Prime can be used as either a whole-home backup during outages or as a day-to-day battery pack, meaning it charges and discharges over a traditional 24-hour period. The RESU Prime comes in capacities of 10 and 16 kWh, and can be installed in pairs to create a whole-home backup for even larger homes that use a lot of electricity.
The average cost of one LG battery, including supporting equipment and installation, ranges from $7,000 to $13,000, depending on battery capacity, installation cost, and location.
Pros of the LG RESU battery
- LG’s RESU Prime batteries come with a warranty that ensures they will retain at least 70% capacity after a 10-year period, which matches the warranty offered by Tesla
- 16 kWh is a large enough home battery size to be adequate for most homes, and can be doubled if necessary
- The Prime batteries are floor-mounted and LG-trained installers can service and repair the batteries onsite if anything goes wrong
Cons of the LG RESU battery
- The average cost of the LG Chem system, including supporting equipment and installation, ranges from $7,000 to $13,000 – depending on your location, battery capacity, and installation charges
- LG batteries are DC-coupled, meaning they can only be used with a hybrid solar inverter or by adding an additional battery inverter, which adds expense and complexity
- LG batteries offer a relatively low continuous power output of 5 and 7 kW for the 10 and 16 kWh batteries, respectively—in order to get higher continuous power output, you have to install 2 full batteries
- The RESU battery uses NMC battery chemistry, like the batteries from Tesla and Generac
What type of home is the LG solar battery system best for?
The LG RESU, like most of its competition, is not intended for those looking to go “off-grid". In fact, the batteries are designed to only work in hybrid grid-tied battery backup systems.
So instead, these batteries are best for energy-conscious homes that require energy coverage during peak consumption periods and unexpected power outages. The 16 kWh system is enough to cover a home for about a day of limited energy use, not several days.
Panasonic EverVolt battery
The Panasonic EverVolt 2 is powerful and comes both AC and DC coupled to meet whatever needs you have. Image source: Panasonic
Panasonic is one of the most recognized and trusted electronics brands in the world, and its solar and battery offerings match the company’s reputation.
Panasonic makes some of the most efficient solar panels on the market, and they’ve been designed to pair seamlessly with the EverVolt battery system. You can also buy the batteries separately and install them with or without solar panels.
If installed as an AC-coupled system (connected to your home’s wiring), Panasonic offers two battery sizes of 11.4 and 17.1 kWh. If installed DC-coupled (connected to your solar inverter), the battery system is expandable from 11-102 kWh for a truly huge whole-home backup system.
Pros of the Panasonic EverVolt battery
- Can be installed either AC-coupled or DC-coupled, allowing for the battery to fit your needs
- Can be sized large enough to provide long-term backup and charge only from solar panels
Cons of the Panasonic EverVolt battery
- Panasonic’s warranty guarantees only 60% capacity after 10 years, falling behind both Tesla and LG
- The cost of AC-coupled Panasonic batteries is between $15,000 and $20,000, which is higher than the AC-coupled Powerwall+
Is there a clear-cut winner among solar batteries?
The battery that will actually work best for your home will largely depend on your budget, your location, your personal energy consumption profile, and what additional features you’d like to see in your system.
The Enphase IQ battery is one of the most popular among installers, and it allows you to take advantage of the entire suite of Enphase products. One company for your inverter and battery needs? That’s a plus in our book.
We think the Generac PWRcell system is best if you’re installing solar panels at the same time. It gives homeowners the best chance to power many different kinds of appliances during a power outage, and its modular design allows you to add more storage modules if your needs change in the future.
If you already have solar panels and are looking for an AC-coupled battery, we recommend the sonnenCore. Although it comes with a higher price tag, this battery is simple to use, safe, and comes with a great warranty.
The batteries from Panasonic are fine products in their own rights, but generally a bit more expensive and harder to get. That said, if you find a Panasonic-certified installer, you can get both panels and batteries that are perfect for each other. If you want something simple and more widely available, the LG batteries are industry standard, and many installers can put them in. Many other battery companies are just getting started, so watch this article to see if one of them rises to the top of our list!
Whether you’re shopping around for solar panels or a battery backup, it is best to speak with a qualified installer to better understand your options. We also suggest you check out the solar panel cost estimator to better understand how solar energy can work for your specific home.
Key takeaways
- The Tesla Powerwall is very popular, but they tend to have long waiting periods.
- Some of the top Powerwall alternatives are the Enphase IQ, the sonnenCore, and the Generac PWRcell.
- The Enphase IQ is offered by many installers, and the company’s reputation suggest the battery will be high quality and you’ll have access to quality customer support.
- Those looking to integrate with a generator or want more control over how much energy storage they install should consider the Generac PWRcell.
- For homeowners who want a premium experience, the sonnenCore solar battery comes with top-of-the-line smart functions and a price to match.
Teddy Theil
Solar Industry Expert
Andy is arguably the most qualified rooftop solar expert in America. He is in a unique position, having founded a large solar company but now being independent of any particular company. He has appeared on CNBC, has been referenced in public hearings concerning the rooftop solar industry ( such as the recent CPUC NEM 3 decision) and has been referenced by many major publications such as the Wall Street Journal, Business Week and many others.