Quick Answer: With solar and battery storage outage backup, your home stays powered because the system separates your house from the grid the moment power fails. The battery then runs your chosen circuits as a small, self-contained power system. In daylight, your solar panels keep producing and refilling the battery so that backup can last several days. Runtime depends on battery size, the circuits you back up, and how much sun Central Virginia gets that week, which drops during winter ice storms.
Key Takeaways
- When the grid fails, a solar-plus-storage system detects the outage, isolates your home, creates its own power supply, and reconnects automatically when utility service returns.
- This planned “islanding” stays safe because a certified isolation device keeps your power off the lines that crews repair.
- A hybrid inverter backup setup, like the Tesla Powerwall 3, handles solar and battery power in one unit.
- Enphase batteries are AC-coupled and pair with Enphase microinverters.
- One battery generally covers critical loads, and whole-home backup generally requires at least two batteries.
- Battery runtime equals usable capacity divided by your average load.
- In Richmond, winter solar output per installed kilowatt averages about 40% of the summer figure.
- Plan your backup around the first one or two days of a winter storm.
How Solar and Battery Storage Outage Backup Works, Step by Step
Every solar and battery storage outage system follows the same six steps when the grid goes down. Each step happens on its own. Most households barely notice the switch.
- Detect. A gateway, backup switch, or system controller senses a drop in grid voltage and frequency.
- Isolate. A relay inside that device opens, separating your home’s wiring from the utility lines.
- Form. The battery’s inverter creates a stable alternating current (AC) signal that the reference household circuits and solar inverters need.
- Supply. The chosen backup circuits start drawing power from the battery.
- Recharge. In daylight, the solar inverters sync to the battery’s signal, resume production, power the home, and send extra energy into the battery.
- Reconnect. Once utility power returns and stabilizes, the system matches the grid and automatically closes the relay.
The isolation device depends on your equipment. A Tesla Powerwall 3 works with a Backup Switch, Backup Gateway 2, or Gateway 3. Tesla’s Backup Switch has a 200-amp rating for standard 120/240-volt home service and automatically detects outages, according to the Powerwall datasheet. Enphase batteries use an IQ System Controller or, in the newest Enphase system, an IQ Meter Collar with the IQ Combiner 6C.
What Is Islanding, and Why Is It Safe Here?
Islanding happens when part of an electrical system runs on its own power source, separate from the main grid. It comes in two forms. The difference between them matters for safety.
- Unintentional islanding happens when a solar system keeps sending power onto utility lines that crews believe are dead. IEEE 1547 sets the anti-islanding rules, and UL 1741 is the test inverters pass to prove they comply.
- Intentional islanding is the planned version a backup-ready home uses. The isolation device opens first, so the battery and panels power only your house.
The isolation device turns a hazard into a safe home microgrid. A standard grid-tied system lacks this device, so it shuts off during an outage. Our outage guide explains that shutdown in detail.
Do You Have to Do Anything When the Power Goes Out?
The switch happens on its own. A backup system handles the changeover, and the manufacturer’s app shows your home running on stored energy. Tesla describes the Powerwall transition as seamless.
Powerwall owners can also turn on Storm Watch. This feature watches severe weather alerts and charges the battery to full from solar or the grid before a forecast storm. For a Central Virginia homeowner, an ice storm warning can top off the battery with zero effort.
Why Do Solar Panels Need a Battery to Keep Running During an Outage?
Solar panels need a battery during an outage because their inverters need a stable AC signal, and the battery provides it when the grid goes down. Panels produce direct current (DC), and household circuits run on AC. A standard grid-tied inverter converts power by matching the grid’s signal, so it stops once that signal disappears.
The battery also absorbs swings in supply and demand. Solar output rises and falls as clouds pass. Demand jumps when a refrigerator compressor or sump pump starts, and stored energy covers those gaps to keep power steady.
| System Type | What Happens During an Outage |
| Solar only | Shuts down for grid safety, even in full sun |
| Battery only | Runs selected circuits until the stored energy runs out, then recharges once the grid returns |
| Solar plus battery | Runs selected circuits and recharges from sunlight during the day |
Each setup serves a different goal. Our backup comparison shows what each option does for your bill and your backup. It also helps you find the right fit for your home.
How Does a Hybrid Inverter Backup System Work?
A hybrid inverter backup system uses one inverter to manage the solar panels, the battery, and your home’s power, including during an outage. It is one of two common ways to connect solar and storage, and AC coupling is the other. Both designs deliver solar and battery storage outage protection. They differ in where the power conversion happens.
Hybrid (DC-Coupled) Systems
The Tesla Powerwall 3 is a hybrid system. Its solar inverter sits inside the battery unit, so the panels feed DC power straight into it. The unit then charges the battery and supplies AC power to the home.
According to Tesla’s Powerwall specs, one unit accepts up to 20 kW of solar, stores 13.5 kWh, and delivers 11.5 kW of continuous power. Fewer separate boxes go on the wall. That makes it a strong fit for new solar and battery installs.
AC-Coupled Systems
Enphase systems convert power at each panel with IQ8 microinverters. The Enphase IQ Battery 5P and IQ Battery 10C include built-in microinverters. This design connects the battery on the AC side.
One advantage shows up during storms. Each panel works on its own, so a shaded or snow-covered panel leaves the rest of the array producing. AC-coupled batteries also suit homes that want to add storage to an existing Enphase solar system.
What Happens When the Battery Is Full, and the Sun Is Still Out?
The system turns solar production down to protect the battery from overcharging. In an AC-coupled system, the battery’s inverter signals the microinverters through small changes in AC frequency, and the microinverters respond by curtailing output. A hybrid unit controls its own solar input.
As the house draws down the battery, production climbs back up. During a long outage, sunny afternoons are best for running heavy chores. Laundry and dishwashing fit well in those hours.
| Feature | Hybrid (DC-Coupled) | AC-Coupled |
| Approved product | Tesla Powerwall 3 | Enphase IQ Battery 10C, Enphase IQ Battery 5P |
| How solar connects | DC panels wire into the battery unit’s built-in inverter | Microinverters convert at each panel, and the battery has its own microinverters |
| Usable energy per unit | 13.5 kWh | 10 kWh (10C), 5 kWh (5P) |
| Continuous power per unit | 11.5 kW | 7.08 kW (10C), 3.84 kW (5P) |
| Islanding device | Backup Switch, Backup Gateway 2, or Gateway 3 | IQ System Controller 3/3G, or IQ Meter Collar with IQ Combiner 6C |
| Often a good fit for | New solar and battery systems | Homes with Enphase microinverters, or storage added to existing solar |
| Manufacturer warranty | 10 years | 15 years or 6,000 cycles |
Specs come from Tesla, Enphase 10C, and Enphase 5P. Convert Solar generally prefers the Powerwall 3. The Enphase batteries remain available where they fit the home better.
Which Circuits Stay On? Backup Loads Panels vs. Whole-Home Backup
The circuits that stay on during an outage are the ones wired to the battery’s backup side. You choose them during design. Two common setups cover most homes.
Critical-Load (Partial-Home) Backup
An electrician moves your most important circuits into a separate backup loads panel, also called a critical loads subpanel. That panel stays powered during an outage. One battery is generally sufficient for this kind of backup, and a short list of circuits stretches stored energy further.
Whole-Home Backup
The isolation device sits at your main service entrance, so every circuit in the house stays available. Whole-home backup generally requires at least two batteries, depending on your energy use and backup goals. Load controls help this setup last longer.
The Enphase Load Controller lets you switch off heavy appliances from the app during a long outage. This control keeps an electric water heater or dryer from draining the battery in a few hours. Smart controls like this help essentials run longer.
How to Choose What to Back Up in a Central Virginia Home
Start with the loads your household needs most. Then add only what the battery can carry. The table below sorts common loads by priority.
| Load | Typical Priority | Why It Matters in an Outage |
| Refrigerator and freezer | Critical | Protects food through a long ice storm |
| Lights in main rooms | Critical | Keeps the house safe after dark |
| Internet router and phone charging | Critical | Supports work, school, and storm updates |
| Medical devices | Critical | Essential for some households |
| Sump pump | Critical where present | Protects basements during heavy rain and snowmelt |
| Well pump | Critical where present | Common in rural parts of Hanover, Goochland, Powhatan, and Louisa counties; keeps water flowing |
| Gas furnace blower | Often included | A gas furnace needs electricity to move heat |
| Heat pump or central air | Whole-home | High draw plus a startup surge; usually needs two or more batteries |
| Electric water heater, range, and dryer | Whole-home | Large loads that drain storage quickly |
| EV charger | Usually excluded | Draws a large amount of power during charging |
Motor-driven loads need extra attention. Well pumps, sump pumps, and heat pump compressors draw a brief surge at startup. Tesla rates the Powerwall 3 for a 185-amp motor start, and the Enphase IQ Battery 5P delivers 7.68 kW peak for three seconds. Your installer should match each motor’s startup demand to the battery before confirming it will run.
How Long Can Solar and Battery Storage Run a Home During an Outage?
A solar and battery storage outage system runs as long as stored energy plus daily solar production keeps pace with your home’s use. Battery runtime on its own follows simple math. Here is the formula.
Runtime (hours) = usable battery capacity (kWh) ÷ average load (kW)
A full 13.5 kWh Powerwall 3 running critical loads averaging 0.75 kW lasts about 18 hours with no solar input. Solar production extends that window. In good weather, daily recharge turns one night of backup into several days.
How Much Solar Recharge to Expect in Central Virginia
Virginia receives about 4.0 to 4.7 peak sun hours per day on average, based on NREL data. A 9 kW array produces roughly 36 to 42 kWh on an average day before system losses. That figure comes from 9 kW multiplied by 4.0 to 4.7 hours.
Seasons change the picture. In Richmond, average output per installed kilowatt is about 2.59 kWh per day in winter and 6.68 kWh per day in summer, according to Profile Solar; for the same 9 kW array, that’s roughly 23 kWh on an average winter day and about 60 kWh on an average summer day. Our winter solar guide covers cold season production in detail.
Illustrative Example: A Three-Day January Ice Storm in Midlothian
This example is for demonstration only and shows one possible outcome. It assumes one Tesla Powerwall 3 (13.5 kWh usable) starting fully charged, a 9 kW solar array, and about 23 kWh of production on a winter average day. Storm day production is set at 25% and 50% of that average. The math also assumes a 0% reserve, zero conversion losses, and daily totals.
| Day | Weather | Solar Produced | Battery at Day’s End, Essentials at 0.75 kW (18 kWh per Day) | Battery at Day’s End, Trimmed Loads at 0.5 kW (12 kWh per Day) |
| Day 1 | Freezing rain, ice on panels | About 6 kWh | 1.5 kWh | 7.5 kWh |
| Day 2 | Overcast, ice shedding | About 12 kWh | Runs about 4.5 kWh short (roughly 6 hours of lost backup) | 7.5 kWh |
| Day 3 | Clear and cold | About 23 kWh | About 5 kWh after recharging from empty | Full (13.5 kWh), with extra solar curtailed |
Trimming loads from 0.75 kW to 0.5 kW keeps backup running through day two and finishes day three with a full battery. In practice, that might mean unplugging a second refrigerator or lighting only the rooms in use. Daily totals also simplify the timing. The battery carries the house through each long winter night before the morning sun arrives.
A summer thunderstorm outage plays out differently. An average summer day produces roughly 60 kWh. One sunny day after the storm can refill the battery several times over.
What Does a Battery Reserve Setting Do?
A backup reserve sets aside part of the battery’s charge for outages, so everyday use leaves that share untouched. For example, a homeowner might choose a 20% to 30% reserve and raise it ahead of a forecast storm. Powerwall’s Storm Watch handles this automatically by charging to full when severe weather is predicted. You adjust reserve settings in the manufacturer’s app.
What Happens If the Battery Runs Out Overnight?
A fully drained battery pauses power to backed-up circuits until it recharges. Restart behavior after depletion varies by product and settings. Ask your installer to explain how your equipment restarts from solar the next morning. A reserve setting and load control are the best ways to keep the battery from reaching empty.
What Central Virginia Outages Mean for Your Solar and Battery Design
Central Virginia’s biggest outages come from ice and falling trees. They often hit during the months with the lowest solar production. This pattern should guide how you size any solar and battery storage outage plan in the region.
Ice Storms Hit During the Weakest Solar Months
Recent winters show the pattern clearly. Each storm below brought down trees and power lines. Outages spread across Richmond and nearby counties.
- February 2021: Over 290,000 customers in Central and Southern Virginia lost power in what the utility called the most destructive ice storm in two decades. A forecaster told VPM the last comparable Central Virginia ice storm came in December 1998.
- January 2025: Wet snow and ice affected nearly 90,000 customers across Central, Western, and Southside Virginia, with Metro Richmond among the hardest-hit areas, WRIC reported.
- February 2025: At one point, over 100,000 customers lost power, and over half of Powhatan County lost service, according to WWBT. WTVR reported that Chesterfield and Henrico counties had the most outages.
Ice and snow on the panels block production until they melt or slide off. That is why the first one or two days of a winter outage lean heavily on the battery. A good design plans for those days first.
Summer Storms and Tropical Remnants Are a Different Problem
Summer thunderstorms and tropical storm remnants also bring down trees and lines. Strong sun usually follows these storms, so daily solar recharge does most of the work. One battery covering essentials can often carry a home for days. Our storm guide shows how panels and racking hold up in high winds.
Design Rules for Central Virginia Homes
- Size for winter. Plan the battery around one or two cloudy days of essential circuits.
- Keep the backup list honest. A short critical loads list stretches stored energy across long outages.
- Use load control. Smart controls stop heavy appliances from draining storage during a long outage.
- Plan for motors. Confirm that well pumps, sump pumps, and heat pumps can start on the battery you choose.
- Consider a generator for whole-home needs across several days. Design the two to work in harmony.
- Prepare before the season. Use our winter prep tips and maintenance checklist so your system is ready for ice storm season.
Can You Add a Battery to Existing Solar or Pair It With a Generator?
Yes, a battery can join most existing solar systems, and it can also work alongside a generator. Both options depend on your existing equipment. An installer reviews that equipment first.
Adding Storage to Existing Solar
A retrofit usually involves three pieces of work. Each one prepares the home to island safely. The list below covers each step.
- Connecting the battery to your current system, often through AC coupling
- Adding an isolation device so the home can island safely
- Moving the circuits you want backed up into a backup loads panel, or choosing whole-home backup
Enphase has announced that the IQ Battery 10C works with existing systems that use other manufacturers’ inverters. An installer should still review your inverter, main electrical panel, and mounting space. That review comes before any retrofit recommendation.
Pairing a Battery With a Generator
A generator covers long, cloudy stretches and pairs well with a battery. It needs proper integration so the generator and inverter work in harmony. On Enphase systems, generator support requires the System Controller 3G. For other equipment, ask your installer which generator setups are supported.
Is Solar Battery Storage Worth It for Central Virginia Homeowners?
The answer depends on whether outages disrupt your household. Solar battery storage pays off mainly through resilience, and bill savings come mostly from the panels. If losing power means a flooded basement, a dry well, spoiled food, or lost work days, a battery earns its place.
Keep these facts in mind as you weigh a solar and battery storage outage plan. Each one shapes a battery’s cost and value. Prices and programs can change over time.
- Cost: Battery storage systems start around $18,000, with final pricing depending on equipment selection, system design, installation complexity, and homeowner energy needs.
- Incentives: The federal Residential Clean Energy Credit ended December 31, 2025, so residential systems installed in 2026 fall outside it.
- Net metering: On April 30, 2026, the State Corporation Commission kept full retail, annual netting in place for customers of Virginia’s largest utility. A May 2026 order confirmed a $1.00 monthly administrative charge. With surplus solar already credited, a battery adds mostly outage protection for these customers. Appalachian Power and electric cooperatives follow their own terms, and our net metering guide explains the details.
- Generators: A standby generator runs large loads as long as fuel lasts. Solar plus storage refills itself from sunlight and runs silently. Some homes use both.
Our battery value guide breaks down cost and value in detail. Solar incentives, utility programs, and eligibility rules can change. Confirm current terms with the relevant agency or utility before making a financial decision.
Why Home Backup Power Is Getting More Attention in Virginia
Virginia’s grid now carries a heavier workload. Fast-growing electricity demand, long waits to connect new generation, and the state’s shift toward cleaner power all affect grid planning and costs. For homeowners, a solar and battery storage outage plan keeps essentials running during grid trouble. These posts explain the forces at work.
- PJM delays: why new Virginia solar waits in line to connect
- VCEA progress: where Virginia stands on its 2045 clean energy goal
- RGGI rejoin: what Virginia’s return to RGGI means for electric bills
- Brightfields solar: how former Southwest Virginia coal mines become solar sites
How Convert Solar Designs Outage-Ready Solar and Battery Systems
Convert Solar designs each solar and battery storage outage system around how your household uses power and what you need to keep running. Every home has a unique situation. The right design starts with your energy use, your roof, and your backup goals.
Here is what that design process includes. Each point below reflects verified company information. Together, these points show how we approach backup.
- Experience: Convert Solar is a residential solar installer with 8,500 systems across Virginia and Maryland, installed by NABCEP-certified professionals.
- Independent recognition: Solar Power World named Convert Solar a Top Solar Contractor for six consecutive years (2021 to 2026), including #22 Top Residential Solar Contractor in the United States for 2026. The rankings reflect the previous year’s installed solar capacity, so they measure completed projects.
- Battery options: Tesla Powerwall 3 is generally the preferred recommendation, and the Enphase IQ Battery 5P and IQ Battery 10C remain available where they fit the home better. Explore our battery storage options.
- Backup design: Our Class A licensed electrical team sets up the backup loads panel or whole-home configuration that matches your goals.
- Warranty: Solar systems carry a 25-year bumper-to-bumper warranty covering materials and workmanship. Battery warranties generally range from 10 to 15 years, depending on the manufacturer and product.
- Pricing: Battery storage systems start around $18,000, depending on equipment selection, system design, installation complexity, and your energy needs.
Convert Solar serves homeowners across Central Virginia, including Richmond, Midlothian, Short Pump, Glen Allen, Bon Air, Mechanicsville, Charlottesville, and Lynchburg. Learn more about our Richmond team. You can also start with our installation guide for Virginia homeowners.
Find Out What Backup Would Take at Your Home
You’re already paying for power. Did you know that you could pay less? Bring your electric bill and outage questions to a Convert Solar consultation, and we’ll review which circuits you want to keep on, how many batteries that takes, and what your roof and electrical panel can support. We’ll also help you decide whether one battery or two fits your goals.
Frequently Asked Questions About Solar and Battery Storage During an Outage
What happens to grid-tied solar panels during a Central Virginia outage?
A standard grid-tied solar system shuts off when the grid fails, even in full sun. Anti-islanding protection stops the inverter from sending power onto lines that crews may be repairing. Production resumes automatically once utility power returns, and a battery with an isolation device keeps your home powered in the meantime.
What is islanding, and why does a solar plus storage system need it?
Islanding means running part of an electrical system on its own power, separate from the grid. A backup-ready home islands intentionally, using an isolation device that separates it from utility lines so the battery can power the house. This setup keeps your home running safely and complies with IEEE 1547 and UL 1741 standards.
Will my solar battery kick in automatically during an outage?
Yes, the switchover happens automatically. A backup-ready system detects the outage, disconnects from the grid, and powers your backed-up circuits automatically. It reconnects when utility power returns, and your installer can confirm the battery is configured for backup.
Is a gateway or automatic transfer switch required for outage backup?
Yes, every backup system needs an isolation device to keep power off utility lines. Tesla Powerwall 3 uses a Backup Switch, Backup Gateway 2, or Gateway 3. Enphase batteries use an IQ System Controller or an IQ Meter Collar with the IQ Combiner 6C, and your installer picks the device that fits your equipment.
How do solar panels recharge the battery when the grid is down?
The battery’s inverter creates its own stable AC signal, and the solar inverters sync to it. During daylight, the panels power your home first and send surplus energy to the battery. Once the battery is full, the system reduces solar output until the home draws the battery down again.
How long can a solar battery keep my essentials running during a long outage?
A fully charged 13.5 kWh Powerwall 3 can run critical loads averaging 0.75 kW for about 18 hours with no solar input. Daily solar recharge can extend that across several days in fair weather. In winter, Richmond’s average output per installed kilowatt sits near 40% of the summer figure, so trimming loads helps most during ice storms.
What happens to solar production on cloudy, rainy, or snowy days during an outage?
Production drops on cloudy or rainy days and keeps going at a lower level. Snow and ice on the panels block output until they melt or slide off, so the first day or two of a winter storm leans on the battery. Cutting extra loads during those days helps the stored energy last longer.
Can a solar battery run my heat pump or air conditioner?
It can, depending on the equipment. Heat pumps and air conditioners draw a surge when the compressor starts and use a lot of power while running. Your installer compares that startup demand with the battery’s power rating, and long heating or cooling runs usually call for two or more batteries.
How many batteries do I need for whole-home backup?
One battery is generally sufficient for critical loads such as the refrigerator, lights, internet, and a sump or well pump. Whole-home backup generally requires at least two batteries, depending on your energy use and backup goals. Convert Solar sizes each design from your usage to show how many batteries your home needs.
How does Convert Solar approach battery backup design?
Convert Solar has installed 8,500 systems across Virginia and Maryland with NABCEP-certified professionals. Our team designs around your energy use, your roof, and the circuits you want to keep running. Tesla Powerwall 3 is generally our preferred battery, with Enphase IQ Battery 5P and 10C options available for homes where they fit best.
