The Generac battery back-up system integrates solar power generation for utility off-set with a battery back-up system that will power a few loads during an outage or help off-set your peak time of use rates. It is important to note both the benefits and limitations when deciding if this is the right solution for your home.
Over the next few paragraphs we will provide an overview of the system for residential 120V/240VAC applications and then go into specific detail on key aspects that you need to know before making a purchase. Not every application will be listed here as there are a variety of options. If you have a specific inquiry and would like a formal quote contact our sales team at firstname.lastname@example.org.
PWRCELL INVERTER + 7.6kW inverter. You do not have to install the batteries upon initially installing the inverter. This system can be used without batteries present and will operate like a grid-tie direct inverter. You can add batteries at a later date.
PWRCELL BATTERY – A minimum of 3 battery modules (9kWh) need to be installed for the back-up system function of the inverter for warranty.
SnapRS (for roof mounted PV systems) – Rapid Shutdown compliant solution for roof mounted PV systems. Roof mounted PV systems will be required to have a single SnapRS rapid level shutdown device on every solar panel. Ground mount systems generally are exempt for modular level rapid shutdown and may not require these unless otherwise specified by the AHJ.
Power Level Optmizer – Required for system operation. Up to 2500 watts of solar power can feed into a single optimizer.
PWRcell Battery Enclosure for Li-Ion Battery – HSBK – Required to house the PWRCell batteries. A minimum of 3 battery modules will be installed. For each additional position you will need either the battery spacer kit (one for every unused battery) or a battery itself.
Spacer Kits for unused battery cells within the PWRCell Battery Enclosure. The battery enclosure fits up to 6 batteries. For any unused position within it, you will need a spacer kit.
Solar panels, Wiring and mounting hardware will be purchased separately.
How much solar will I need?
Solar panels* – there are a variety of solar panels that you can use for this system. Most systems will have 7-10kW of solar feeding into the inverter.
This is not an off-grid inverter system. This is designed to be a grid-tie battery back-up, or time of use of-set and the utility grid should be available.
Can I stack multiple batteries?
You can stack up to two PWRCELL Batteries with a single inverter system, for up to 34.2kWh of storage.
What kind of loads can I back up?
The inverter is rated to 8kW (33.3A) in backup / islanded mode.
When the grid is up, its continuous output is 32.0A. Fridge, freezer, lights and critical loads under 32.0 amps continuous.
Can I stack multiple inverters?
At this time you can only have a single inverter within the system. There is only a single AC input for the utility grid. This inverter does not have an additional AC input for a generator, nor is a generator supported for the AC input currently available. This may be available at another date.
What is the minimum number of battery cells for the system?
You need a minimum of 3 PWRCELL Batteries to have this system function in any of the modes except for the grid-tie only.
Can I choose my own batteries?
Generac supports their PWRCELL Batteries only at this time and it is not recommended to use other brands of LiFe Batteries with this system.
Do you have to be a certified installer to install the Generac battery back-up system?
Generac offers installer training that you can sign up for here. Installation of this equipment is limited to certified Generac installers or the warranty will be void.
Recommended to read all user manuals and installation guides prior to ordering.
*If you have an existing grid tie system and are interested in adding battery storage – there are other solutions available that will allow you to back up your system without having to replace a fine working system (AC Coupling).
There are 5 programable modes for the Generac inverter system:
Priority Back-Up – Inverter prioritizes keeping the batteries charged and ready for grid interruption using solar or grid power. If the battery is not fully charged all available solar power is used to charge the battery. When the available solar power is lower than the battery input rating the inverter uses the grid power to expedite battery charging.
Clean Back-Up – Inverter prioritizes keeping the batteries charged and ready for grid interruption using solar power only. If the battery is not fully charged the inverter will use all available solar power to charge the battery.
Grid Tie – Inverter functions as a conventional grid-tied inverter system. The system power local loads and when generation exceeds load demand, excess power is exported to the utility grid for net metering and other credits. (Note: This mode is only used when there is no battery storage installed.)
Self-Supply – In self-supply mode the inverter prioritizes powering local loads using solar and/or stored power first. This mode is optimal in markets where net metering is unavailable or unfavorable making battery-stored power more economically attractive than grid-provided power
Zero Export – This mode is used in areas where PV systems are prohibited from back-feeding the AC grid. With this function enabled the inverter will limit solar generation such that it exactly matches the power consumed by local loads resulting in no exported power.