The PWRcell system has five operational modes to manage the distribution of power — Clean Backup, Priority Backup, Self Supply, Grid Tie, and Sell. Homeowners can select the mode based on what they would like the system to do.

Self Supply Mode

In Self Supply Mode the system prioritizes powering your home using solar and/or stored power first. This is mode is optimal if your utility company imposes time-of-use rates or does not have a net metering program, making energy generated by your solar panels a cheaper option for you.

 

Priority Backup Mode

In Priority Backup Mode, the system prioritizes keeping the batteries charged 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 power rating, then the system uses grid power to expedite battery charging. This mode is optimal when you know a power outage is coming and you need to charge your battery as quickly as possible.

 

Clean Backup Mode

In Clean Backup mode, the system prioritizes keeping your solar battery charged using only energy collected from your solar panels. If the battery is not fully charged, your solar panels use all available solar power to fill the battery. Then your solar panels will power your home and send any excess energy back to the grid. Clean Backup Mode is used to make sure your battery is full, in preparation for the next grid outage.

 

Grid Tie Mode

In Grid Tie Mode, electricity generated by your solar panels is used by your home first, and any excess is sent back to the grid for a credit on your electric bill. Grid Tie mode is intended for use with systems that do not have a battery.

 

Sell Mode

In Sell Mode, you can maximize the export of the energy generated by your solar system and sell it back to the utility company. Sell mode is used when you want to prioritize selling all your solar energy instead of using it.

 

Some utility companies have Time of Use charges. Time of use charges occur when energy use is in peak demand, and typically is a higher cost. Peak demand periods usually occur in the early morning hours, when families are getting ready for school and work, or in the evenings, after 5p. Using PWRcell’s Time of Use Scheduling will cycle the system modes to maximize your saving by using both battery storage and solar production.  ​

PWRcell helps you save money by supplementing your current energy use and using the system’s stored energy instead of relying on the grid when power is most expensive. PWRcell can also help you offset utility bills with net metering. 
 
Each billing period, the power you used is offset by the power you sent back to the utility company. Your bill for energy will only be for the difference or the “net.” Your monthly bill will include the basic service charge, taxes and other adjustments. Net metering incentives or credits vary by state and utility.  If you’re interested in net metering, talk to your installer to confirm:

• Your system is set to the correct operation mode
• You have permission to export energy and sell it back to the grid.
• You have a bi-directional meter which records energy flowing from the grid and spins the opposite way to subtract the energy your system supplies back to the utility company

If you generate more energy than you use during your monthly bill cycle, your bill will have no kilowatt-hour charges, and you will receive kilowatt-hour credits that will be applied to your future electric bills. You can monitor your electricity usage and get an in-depth look at where electrical waste occurs within your home by using Generac’s home energy monitoring system, PWRview.



 
 
With PWRview you can also see how much energy you’re selling back to the grid on a monthly basis.
 
 
 

If there is a utility power outage, PWRcell will seamlessly disconnect (or island) from the utility grid allowing you to power the items in your home that you have deemed essential, during an outage. The system will supply power from its solar panels during the day and from its batteries at night. The PWRview App will notify you when your system has islanded. 
 

If you know a power outage is coming:

• Disable your Time of Use Schedule if you have one
• Charge your battery and change the system mode to ‘Priority Backup’. ​
• Shut down electronics that will not be backed up. ​
• Become familiar with the circuits that will be powered by performing a simulated power outage:
  • Any circuits that are managed with SMMs. 
  • Circuits that will always be on or off
• Large appliances consume battery energy more rapidly than essential loads, so keep usage of these items to a minimum. ​

If you have a PWRcell battery, it can provide supplemental power for your backup loads. Use the PWRview app to check on your solar production and battery charging.  If your battery is not charging throughout the day consider reducing your energy consumption to prolong the battery life. ​
 

If a hazardous situation such as fire or flooding should occur, immediately shut down your PWRcell system, by pushing the red button on the PWRcell control panel.



If utility power fails, and your PWRcell system does not go into Islanding Mode, it’s important to know if you have either a transfer switch or a protected loads panel, so your installer or Generac customer support can help you troubleshoot the issue. For reference, a description and picture of both are listed below.



Transfer switch – A transfer switch provides safe connection between your PWRcell system and the electrical appliances of your home. This makes it possible to quickly switch power from the utility source to the generator during an electrical outage. Transfer switches are typically installed directly next to the electrical panel of your home. This allows PWRcell to connect to a single source instead of multiple appliances.

Protected loads panel – A protected loads panel provides limited backup power to dedicated electrical outlets located inside the panel. These protected load panels will not supply power to the entire home during a grid outage. In the case of a power outage, the battery energy storage system will automatically switch into off-grid mode and supply power to the protected loads panel.

For help with any issues with your PWRcell system, please reach out directly to your local system installer. If your installer is unavailable, reach out to Generac Customer Support by phone at 888-GENERAC, or online at Generac.com.

Your PWRcell system will require some light maintenance​ on an annual basis. Below are a few tips for upkeep:
 

• Clean the exterior of the enclosure with a soft cloth​
• Ensure the surrounding area is free of anything that could obstruct airflow​
• Inspect the unit and look for conditions that could hinder performance or safety​ such as blocked vents​, dirty intake filters​, loose/missing hardware​, or broken electrical connections​

 
While following the tips above will help increase the life expectancy of your system, the more complex aspects of maintaining your unit are best left to a professional technician or installer. To find an installer located near you, please visit our dealer locator page.

CT - Current Transformer, a way to measure the flow of electricity through the conductors. This helps measure consumption and backfeed from inverter  

Consumption - The amount of Energy used in the home or business 

Backfeed - The amount of energy sent back to the grid/utility from the inverter  

Island - Inverter operating separately from grid connection  

Meter - Round device that utility uses to measure energy in/out for Net Energy Metering (See page regarding the different meters

ATS - Automatic Transfer Switch, switches between energy sources usually the grid vs the inverter. Automatic because it is triggered by a signal from the inverter to switch from one source to another

SMM - Smart management Module, part of load management. An external enclosure that wires in between the loads and the breaker. It is a relay switch that is intelligently controlled dependent on available power.

Transfer switch - A transfer switch provides safe connection between your PWRcell system and the electrical appliances of your home. This makes it possible to quickly switch power from the utility source to the generator during an electrical outage. Transfer switches are typically installed directly next to the electrical panel of your home. This allows PWRcell to connect to a single source instead of multiple appliances.

Protected loads panel - A protected loads panel provides limited backup power to dedicated electrical outlets located inside the panel. These protected load panels will not supply power to the entire home during a grid outage. In the case of a power outage, the battery energy storage system will automatically switch into off-grid mode and supply power to the protected loads panel.

Load Management - A feature to manage the amount of energy being drawn during islanding

SnapRS - Inline switch that is required for most installs and for rapid shutdown. When the red shutdown button is pushed on the inverter, the REbus devices are disabled the PV will be isolated from module to module due to these devices. One max installed per solar module. Exceptions are ground mounts and carports do not require Rapid Shutdown safety requirements

Battery Spacer - If there is an odd number of battery modules installed, the space is required

REbus - This is native to PWRcell and is the DC power flowing through the system. A Rebus device runs on the ~400V DC system

1-pole vs 2-pole - 120v vs 240V. 240v breaker uses 2 slots in the distribution panel

3-Phase - A configuration from the utility designed for commercial properties usually. Has the same voltage for 1-pole 120V devices but does not support 240V (usually 208V instead). X7602 inverter will not connect, they would need the X11402. X11402 inverter requires a 3-phase wye configuration which refers to a separate neutral

Conductor - A wire usually copper and sometimes aluminum

Net Energy Metering (NEM) - This is an agreement with the utility that allows power to be credited when fed back to the utility. This also sometimes requires upgrading to a compatible bi-directional meter

Export / Import - Sending power to the utility vs taking power from the utility

Feed/Feeder - A conductor that is upstream

Land - Where an electrical connection resides

AC / DC Disconnect - A breaker or switch on an AC/DC electrical line

Main Breaker - The breaker the turns off the entire panel

Enclosure - They electrical box that components reside inside

NEMA rated - System that determines to what degree is weather resistant. NEMA 3R means it can be outside, NEMA 4X (for SnapRS) is even more robust

Photovoltaic (PV) - Solar modules

Array - Cluster of solar modules in one area such as a roof plane

ESS - Energy Storage System aka battery