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Nov 30, 2023

The 6 Best Solar Batteries in June 2023

Faith Wakefield is a writer based in North Carolina. She holds economics and English degrees from UNC Chapel Hill, and her work has been featured on EcoWatch, The World Economic Forum and Today's Homeowner. In her free time, she loves to binge-watch personal finance videos on YouTube, collect books and spend time in nature.

Karsten Neumeister is an experienced energy professional with subject-matter expertise in energy policy and the solar and retail energy industries. He is currently the Communications Manager for the Retail Energy Advancement League and has prior experience writing and editing content for EcoWatch. Before EcoWatch, Karsten worked for Solar Alternatives, curating content, advocating for local renewable energy policy and assisting the solar engineering and installation teams. Throughout his career, his work has been featured on various outlets including NPR, SEIA, Bankrate, PV Mag and the World Economic Forum.

Solar batteries store excess energy from your solar panels to use at night, on cloudy days or during power outages. See how adding them to your solar system allows you to use more of the energy you’re generating in this guide to the best solar batteries.

We’ve thoroughly researched the top solar battery options on the market, reviewing each model's warranty, power rating, capacity, longevity and more. Our picks for solar batteries are SunPower SunVault, Tesla Powerwall and SonnenCore+, but the best battery for you will depend on your energy needs and preferences. This includes whether you’re installing a battery on a new or existing solar system, how much energy storage you want and your energy usage.

Integrating a solar battery into a new or existing solar panel system almost always requires professional installation. Select one of our top solar companies from the panel below to get connected with a solar battery installer.

When choosing a solar battery, it's important to consider factors like storage capacity, power rating, cost and other specifics.

Storage capacity is measured in kilowatt-hours (kWh) and refers to the amount of energy your solar battery can store for later use. The amount of battery storage capacity you need depends on your average energy usage and preferences. For example, consider how long you would need to run your home on backup power in the case of an outage.

Power rating refers to the rate at which your solar battery can discharge or release stored energy. A higher power rating means your battery can deliver more power at once and meet higher energy demands.

Cost is a major consideration when choosing a solar battery — a single solar battery can cost $10,000 or more. Keep in mind that solar battery installation, additional parts and shipping can add several thousand dollars to your final cost. We recommend getting a quote from a solar provider tailored to your home for the most accurate pricing.

Performance metrics like a battery's depth of discharge (DoD) and round-trip efficiency are also important considerations. DoD is the amount of energy you can use from your battery before it needs a recharge. Round-trip efficiency refers to how much of a battery's stored energy you can use as output energy. The higher your round-trip efficiency and DoD, the more you’ll be able to take advantage of your battery's capacity.

See how our top-rated solar batteries compare:

Battery

Storage Capacity

Continuous Power Rating

Cost

Installers

SunPower SunVault

Available in 13 kWh or 26 kWh

6.8 kW

$17,000–$32,000with all costs included and depending on model

SunPower or Blue Raven Solar

Tesla Powerwall 2

13.5 kWh

5.8 kW

$9,200 before installation or $11,500 with installation

ADT Solar, Sunrun, Sunnova or local installers

SonnenCore+

10 kWh or 20 kWh

5 kW

$12,000–$16,000

Local installers

Enphase IQ

10.08 kWh

3.84 kW

$8,200 (before shipping and installation)

ADT Solar, Green Home Systems or local installers

Generac PWRcell

Modular capacity between 9 kWh and 18 kWh

4.5 kW–11 kW (depending on system size)

$10,000+

Local installers

LG Chem RESU

Available in 9.6 kWh or 16 kWh

5 kW

$9,000 before shipping and installation

Green Home Systems or local installers

Below are our top six solar batteries:

SunPower manufactures some of the best solar panels on the market in terms of efficiency and durability. The SunPower SunVault battery complements any SunPower system with a large energy capacity of 13 kWh and an above-average continuous power rating of 6.8 kW. It also includes an excellent warranty that doesn't limit the number of cycles your battery can discharge like some other companies. The SunPower SunVault is our top choice for homeowners who already have SunPower solar panels or are planning to install a SunPower system. Unfortunately, SunPower SunVault is not compatible with non-SunPower brand solar panels.

Photo courtesy of SunPower

SunPower offers two models of its SunVault battery system: the SunVault 13 and the SunVault 26. The SunVault 13 offers 13 kWh of battery power, while the SunVault 26 offers 26 kWh.

The SunVault 26 system consists of the SV-BASE13-12-A and SV-ENERGY13-12-A models to expand the amount of power a system can hold. The SunVault 12 only consists of the standard SV-BASE13-12-A model.

Warranty

10-year warranty with unlimited cycles and 70% guaranteed capacity*

Cost

SunPower does not disclose pricing information, but customers report the 13 kWh model costs $17,000 to $20,000, while the 26 kWh model costs $24,000 to $32,000 with installation.

Storage capacity

Available in two sizes: 13 kWh or 26 kWh

Continuous power rating

6.8 kW

Round-trip efficiency

85%

Depth of discharge

Not disclosed

*SunPower guarantees its batteries will retain at least 70% of their initial energy capacity by the end of the 10-year warranty period. This percentage may vary based on the manufacturer.

SunPower manufactures its solar products and uses certified partners to install batteries and other solar equipment in all 50 U.S. states. Blue Raven Solar is another popular solar company that installs SunPower SunVaults. If you’re interested in the SunPower SunVault, click below for a free, no-obligation quote.

The Tesla Powerwall is one of the most popular solar batteries available, featuring a sleek design with strong performance and efficiency. The Tesla Powerwall 2 is also compatible with any solar panels, not just Tesla systems.

Due to its popularity, the Tesla Powerwall is frequently on backorder and only comes in one size. However, you can add more Powerwalls to expand your system.

To learn more, check out our full review of the Tesla Powerwall.

Photo courtesy of Tesla

The Tesla Powerwall comes in two models, both with 13.5 kWh of storage capacity: the Powerwall 2 and the Powerwall+. The key difference is that the Tesla Powerwall 2 is just a solar battery, while the Tesla Powerwall+ is both a solar battery and inverter.

The Powerwall+ is ideal for new solar installations, while the Powerwall 2 is more suitable for retrofitting into an existing solar system.

Warranty

10-year warranty with an unlimited cycle and 70% guaranteed capacity

Cost

$9,200 without installation and $11,500 with installation. Per-unit cost decreases if you buy more than one.

Storage capacity

13.5 kWh

Continuous power rating

5.8 kilowatts (kW)

Round-trip efficiency

90%

Depth of discharge

100%

Although you can order a Powerwall directly through the Tesla Website, the company requires that Tesla Certified Professionals install all batteries.

Several nationwide solar panel companies, including ADT Solar, Sunrun and Sunnova, install the Tesla Powerwall. You can also use the search tool on Tesla's website to find an installer in your area.

Sonnen offers a variety of battery models that can adjust to your energy needs and budget. For example, you can adjust the energy capacity of your Sonnen ecoLinx by 2 kWh increments up to a massive 30 kWh battery. However, the high price point is out of reach for many customers.

The SonnenEvo and SonnenCore+ are more standard batteries available in 10 kWh and 20 kWh sizes. Plus, the SonnenEvo is alternating current or AC-coupled, meaning you can use it as an energy storage device whether or not you have solar panels.

Photo courtesy of Sonnen

Compare Sonnen's solar battery models:

Warranty

10-year warranty with 10,000 cycles and 70% guaranteed capacity for the SonnenEvo and SonnenCore+; 15 years with 15,000 cycles for the ecoLinx

Cost

$12,000–$16,000 on solar wholesale websites

Storage capacity

Modular battery capacity between 10 kWh and 30 kWh

Continuous power rating

5 kW

Round-trip efficiency

86%

Depth of discharge

100%

Sonnen partners with solar companies throughout the U.S. to install its solar batteries. You can find a Sonnen solar battery installer on the Sonnen website.

Enphase manufactures a variety of solar energy products, including solar panels, microinverters, and of course, solar batteries. With a 96% round-trip efficiency and a 100% depth of discharge, Enphase offers some of the most efficient batteries available today.

The standard Enphase IQ battery setup offers 10.08 kWh of battery storage, though it can be expanded.

Photo courtesy of Enphase

Warranty

10-year warranty with 4,000 cycles and 70% guaranteed capacity; optional 5-year warranty extension is also available

Cost

$8,200 from solar wholesalers before installation or other parts

Storage capacity

10.08 kWh

Continuous power rating

3.84 kW

Round-trip efficiency

96%

Depth of discharge

100%

Several top solar providers install Enphase solar batteries, including ADT Solar, Green Home Systems, Semper Solaris and Freedom Solar Energy.

Click below to speak with a solar professional about your Enphase solar battery installation today.

The Generac PWRcell is outfitted with a cabinet that protects your solar battery from the elements and can help extend its lifespan. You can expand your battery cabinet by adding additional battery modules or cells. You can achieve up to 18 kWh of storage from a single battery cabinet — or twice that when you add another.

Photo courtesy of Generac

Generac customers can choose from four different system capacities. Each system is built with 3 kWh battery modules.

If you want an even larger battery bank, you can install more than one PWRcell cabinet, expanding your Generac energy storage system up to 36 kWh.

Warranty

10-year warranty or 7.56 megawatt-hours (MWh) of energy throughput per module, whatever comes first

Cost

The cost of a PWRcell battery system, including an inverter, battery storage cabinet and three battery modules, starts at $10,000.

Storage capacity

Between 9 kWh and 18 kWh for a single battery cabinet or up to 36 kWh with multiple PWRcell battery cabinets

Continuous power rating

Between 4.5 kW and 11 kW depending on the storage capacity of your system

Round-trip efficiency

96.5%

Depth of discharge

84%

Generac has a network of installers across the U.S. that can install your PWRcell system.

LG stopped making solar panels but still manufactures its state-of-the-art line of solar batteries. LG's solar batteries are compact and, thanks to a direct current (DC) system, have an industry-leading round-trip efficiency of 95%.

One downside of the LG RESU is that only the RESU prime models guarantee 70% battery capacity after 10 years. The standard models — the RESUL Gen2 — only guarantee 60% capacity under a limited warranty.

Photo courtesy of LG

Compare LG's solar battery models:

Warranty

10-year warranty with a guaranteed retention capacity of 60%–70%, depending on the model

Cost

A 16 kWh model starts around $9,000 on solar wholesale sites, before shipping and installation

Storage capacity

9.6 kWh or 16 kWh, depending on the model

Continuous power rating

5 kW

Round-trip efficiency

95%

Depth of discharge

95%

LG requires that a qualified professional install its solar batteries.

Green Home Systems, one of our top-recommended solar providers, installs LG solar batteries. You can also find an LG solar battery installer in your area by inputting your zip code on the LG website.

You can differentiate solar batteries by their chemical composition. Lead-acid and lithium-ion batteries are the two most popular types.

Lead-acid batteries have been around for many years. They take longer to charge and have a shorter lifespan than lithium-ion options. They’re also bulkier and heavier. However, they are relatively low-cost and reliable. Lead-acid batteries have become more popular for off-grid systems than residential installations.

Lithium-ion varieties are the most common type of solar battery, with Lithium Nickel Manganese Cobalt Oxide (NMC) and Lithium Iron Phosphate (LFP) being the most popular. NMC batteries have older technology but are more widely used. They provide ample power but are smaller in size. NMC batteries also contain cobalt, which makes them hard to recycle.

LFP batteries are more eco-friendly and can be recycled more easily than NMC batteries. They use a new technology that provides a longer lifespan and better efficiency than NMC varieties.

Yes, you can add solar battery storage to your existing solar power system. However, not every solar battery is compatible with every solar array. For example, Enphase and SunPower brand batteries are only compatible with Enphase and Sunpower brand solar panel systems, respectively.

On the other hand, Tesla Powerwall and Sonnen solar batteries are compatible with almost any solar array. You can also retroactively connect either brand of battery to your renewable energy system.

If you already have a solar system with a solar battery, but your energy needs have increased or changed, you can typically expand your battery backup system by connecting more units. We recommend speaking with your solar installer to decide which solar energy storage solution best fits your needs.

Solar battery storage systems help homeowners make the most of their solar power systems. They store the excess energy your system generates so none of your power goes to waste.

The SunPower SunVault and Tesla Powerwall are our top picks for solar batteries thanks to their sleek design, large capacities and excellent continuous power ratings. However, our other picks for the best solar batteries are still excellent options depending on your individual needs.

To get started with your home battery installation, get connected with one of our trusted solar battery installers today.

It depends. If your state does not offer net metering credits at the retail rate or you are subject to a time-of-use energy payment program, you’ll save the most on your electricity bill when you install a solar battery. But you probably won't save as much if your utility offers a good net metering program that pays you for any excess energy your panels generate.

Yes! If you connect your solar battery to your solar panel system, you are eligible for renewable energy equipment incentives. That includes the 30% federal solar tax credit. Your state may also offer other incentives for solar battery systems.

No, you do not necessarily need a solar battery to power your electric vehicle charger. You can directly power the charger using your solar panels, or connect the charger to the energy grid and use net metering to offset the cost of the electricity you use outside of peak sunlight hours.

It depends. The upfront cost of a solar battery is high enough that most people will not see enough electricity bill savings to cover the cost of the battery over its lifetime. However, even if you aren't saving money with a solar battery, solar batteries allow you to use stored energy during power outages or on cloudy days.

However, the solar industry has been advancing rapidly, reducing costs and making solar batteries more financially viable for homeowners.

We closely evaluated seven crucial factors according to our solar panel installation company methodology to rank the best providers in the industry. Based on a 100-point scale, we came up with each provider's score out of five stars. Here's how we assessed each company:

Faith Wakefield is a writer based in North Carolina. She holds economics and English degrees from UNC Chapel Hill, and her work has been featured on EcoWatch, The World Economic Forum and Today's Homeowner. In her free time, she loves to binge-watch personal finance videos on YouTube, collect books and spend time in nature.

Tori Addison is an editor who has worked in the digital marketing industry for over five years. Her experience includes communications and marketing work in the nonprofit, governmental and academic sectors. A journalist by trade, she started her career covering politics and news in New York's Hudson Valley. Her work included coverage of local and state budgets, federal financial regulations and health care legislation.

Karsten Neumeister is an experienced energy professional with subject-matter expertise in energy policy and the solar and retail energy industries. He is currently the Communications Manager for the Retail Energy Advancement League and has prior experience writing and editing content for EcoWatch. Before EcoWatch, Karsten worked for Solar Alternatives, curating content, advocating for local renewable energy policy and assisting the solar engineering and installation teams. Throughout his career, his work has been featured on various outlets including NPR, SEIA, Bankrate, PV Mag and the World Economic Forum.

Keep In Mind SunPower SunVault: Our top pick Tesla Powerwall 2: SonnenCore+: Enphase IQ: Generac PWRcell: LG Chem RESU: Cost and payment options (20 points): Services (20 points): Reputation (20 points): Warranty (15 points): Customer Support (10 points): Industry Experience (10 points): Sustainability (5 points): Tori Addison Karsten Neumeister
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