While shopping for storage solutions, it can be hard to break down which products come with an integrated inverter, which will need an additional inverter, and how many boxes will be installed on your wall. This is one of the key factors to pay attention to when comparing storage solutions, as it will impact the overall efficiency and cost of your battery setup and how you integrate it into a solar panel system.
Here's a breakdown of this info for some of the biggest storage companies in the market today:
Batteries or battery packs without an integrated inverter must be paired with an external, third-party inverter to connect to your solar panel system and home.
One of the best-known–and most installed–products in the market is the LG Chem RESU10H, a battery that does not come with an integrated inverter. It must be connected with a storage inverter to interface with your solar panel system and your home. It's most frequently connected with a SolarEdge StorEdge inverter, which has recently been upgraded to the EnergyHub inverter. The RESU 10H can be installed as a part of an AC or DC-coupled solar plus storage system. Because it only requires one inversion process (from DC to usable AC electricity in your home), it boasts one of the highest true round-trip efficiencies of any product in the market when looking at the energy ultimately usable in your home.
Another well-known battery cell manufacturer, SimpliPhi's products, must be paired with an external inverter. Its modular and stackable battery packs provide the storage alone but are "inverter agnostic," which is the industry's way of saying they work with anyone. Its most popular battery is the 3.8 kWh battery module, which can be stacked and nestled next to your inverter on the wall next to your electrical panel.
Blue Planet Energy
A more recent entrant into the energy storage space, the Hawai'i-based Blue Planet Energy's products are "grid-optional" batteries. The company integrates battery modules into a "cabinet" that houses and provides the electrical connections for each battery module. The Blue Ion 2.0–their flagship residential product–is a battery-module-filled cabinet that can integrate with several inverter brands, including Sol-Ark, Schneider, Enphase, and SolarEdge, in AC-coupled designs.
Storage systems with an integrated storage inverter can be AC-coupled with solar panel systems and your home. They can convert the usable AC energy from your home into storable DC energy and back again. Note: If you plan to pair these batteries with a solar panel system, you'll also need to install an inverter to convert the generation from your solar panels into usable electricity in your home.
The manufacturer of luxury energy storage systems, sonnen, builds energy storage systems with an integrated inverter. These batteries can only be AC-coupled, meaning their input must be alternating current electricity, making them an ideal option for retrofit systems. As a result, even though the sonnen battery has its own storage inverter, you'll still need an external, third-party inverter if you pair your sonnen with a solar panel system.
The leading manufacturer of microinverters for the residential market in the US, Enphase, recently launched a new energy storage system, the Encharge batteries. These batteries come with Enphase IQ8 microinverters incorporated into the individual battery modules inside the storage system. If you pair the Encharge system with a solar panel system that uses Enphase microinverters, the electricity from your solar panels will already be AC by the time it reaches your storage system.
Storage systems with an integrated hybrid inverter can cover both the production from your solar panels and the requirements of your storage system, allowing for seamlessly integrated solar plus storage solutions.
When Generac, the leading provider of home backup generators in North America, acquired Pika Energy, they received both the technology behind Pika's energy storage system as well as Pika's powerful hybrid inverter. Like other options in this category, Generac's PWRcell batteries excel when DC-coupled with new solar plus storage systems.
Like Generac, Electriq Power is an American-made energy storage system manufacturer that has integrated Panasonic battery cells into a unique battery enclosure paired with a powerful hybrid inverter. Electriq's batteries come in both DC or AC coupled versions, allowing them to be installed in new solar or as a retrofit.
Long a producer of battery cells and modules used by other storage companies (see above), Panasonic released its integrated energy storage system at Solar Power International in 2019. While their original storage product, the EverVolt, has separate DC and AC inverters based on coupling needs, their new EverVolt 2.0 comes with a built-in hybrid inverter that can be either DC or AC coupled.
A few options in the market today can either come with or without their own integrated inverter. You may recognize the primary company that offers this option.
The best-known storage manufacturer on the market, Tesla, provides its Powerwall 2 in two varieties: one with an integrated inverter and one without. This affords installers with a certain level of flexibility to choose the option that makes the most sense for their application and system design. Installing a standalone storage system (like this one in Green Mountain Power's pilot program)? You can install a Powerwall 2 with its own integrated inverter. Would you like to install a Powerwall as a part of a DC-coupled solar plus storage system? There's an option for that too.
It's important to note that only the option with the built-in inverter is commercially available in the US market. This means you'll have to pair your Powerwall 2 with an external inverter when installing a Powerwall with a solar panel system since it requires AC electricity as the input. This also decreases the overall system efficiency of solar + storage systems with a Powerwall, as with other batteries with an integrated storage inverter.
If you're interested in comparing your options for adding storage to a solar panel system, we can help! Register for a free account on EnergySage today to join the country's largest online marketplace for solar. We'll get up to seven custom quotes on your behalf from solar companies in your area. When you sign up, let us know that you're interested in storage; you can even say why you're interested in helping installers size the system. Happy solar shopping!