Learn: backup power
Solar vs Generator: Which One Keeps the Lights On?
Solar cuts your bill every sunny day but shuts off in an outage unless it has a battery. A portable generator only helps in an outage and runs on fuel. Many homes end up with solar for the bill and a generator hookup or battery for backup.
Reviewed 2026-09-24
Google reviews
1,463 across four profiles
Family-owned
Since 1996
Licensed and insured
VA 2705031092
Answer first
The short answer
Solar and a generator solve different problems. Solar lowers the electric bill all year, but a grid-tied array shuts off in an outage unless it has a battery and transfer equipment. A portable generator does nothing for the bill and only runs in an outage, on fuel, outdoors. For backup, compare a generator hookup at $900–$2,500 with a whole-home battery at $6,000–$15,000+.
- Solar alone: lower bills, no outage power.
- Solar plus battery: lower bills and outage power for selected circuits.
- Portable generator hookup: outage power from a generator you own, with an inlet and a listed transfer switch or interlock, typically $900–$2,500.
- AJ Long Electric installs generator hookups only. We do not sell generators or do fuel work.
What each option actually does
The comparison is really three options, because solar with and without a battery behave differently in an outage.
| Question | Solar only | Solar plus battery | Portable generator hookup |
|---|---|---|---|
| Lowers the monthly bill | Yes | Yes | No |
| Power during an outage | No | Selected circuits, within battery limits | Selected circuits, while fuel lasts |
| Fuel | None | None | Gasoline, propane, or dual fuel |
| Where it runs | Roof | Roof and a battery location set by the listing | Outdoors only, away from windows |
| Starts in an outage | Shuts off | Switches automatically when designed to | You set it up and start it |
| Typical installed range | $19,000–$34,000 | $30,000–$43,500+ | $900–$2,500 for the hookup; generator not included |
The solar range is a typical 8 to 12 kW rooftop. The solar plus battery figure is a typical 10 kW example.
Why solar panels go dark in a blackout
A grid-tied inverter is required to stop exporting when the grid fails, so it cannot push power into lines that crews believe are dead. Dominion's net metering page explains the precaution and adds that the only way to supply your home from distributed generation during an outage is an energy storage system and a transfer switch.
The Department of Energy describes how that works when storage is present: a solar system with a battery detects the loss of grid power, islands the home, and reconnects when service returns. Without storage, a sunny outage day still means a dark house.
Where a generator wins
A portable generator runs as long as you can refuel it safely, so it handles multi-day outages in cloudy weather when a battery may not refill. It costs less up front than a battery, and many homeowners already own one.
The weak points are safety and effort. Ready.gov's outage guidance says to use a generator only outdoors and away from windows, because of carbon monoxide. Someone has to be home to roll it out, connect it, start it, and refuel it. It is also noisy and needs regular exercise and maintenance to start when you need it.
The connection is where homeowners get hurt. An extension cord through a window is not a plan, and backfeeding a dryer outlet can energize the utility lines. The safe connection is an outdoor inlet and a listed transfer switch or interlock at the panel. That is the part we install.
What a generator hookup includes
Our published generator hookup range is $900–$2,500. It covers the electrical path from a generator you own to the panel, and nothing that burns fuel.
- An outdoor power inlet, mounted where the generator can run safely away from windows and doors.
- A listed transfer switch or a listed interlock at the panel, so the house can never draw from the generator and the grid at the same time.
- The circuits you choose to power, matched to the generator's rated output.
- The permit and inspection the jurisdiction requires for the work.
Where solar plus a battery wins
A battery has no fuel, no exhaust, and no one has to be home to start it. When the design includes automatic transfer, the backed-up circuits switch over on their own. During the day, the array can recharge the battery, within the equipment's limits. The same battery can shift solar production into the evening and may one day earn credits through Dominion's Virtual Power Plant pilot.
The limits are capacity and cost. A battery holds a fixed amount of energy, so the circuit list matters, and a string of cloudy winter days can drain it. Whole-home integration typically runs more than a generator hookup, but it also works every day, not only in outages.
Doing both
Plenty of Northern Virginia homes combine them: solar for the bill, and a generator hookup as the outage plan until a battery makes sense. The two have to be designed together. A generator interlock and a solar backfeed breaker share the same panel, and some battery systems accept a generator input while others do not. We lay out the panel once so each piece has its place and the transfer equipment keeps the sources separate.
If the panel itself is the limit, the proposal says so. A 200-amp panel upgrade is published at $3,500–$7,500.
Straight answers
Questions
- Is solar better than a generator?
- For the electric bill, yes; a generator does nothing for it. For outages, solar alone does not help because it shuts off with the grid. Solar with a battery, or a generator hookup, is the outage answer.
- Can I use a generator with solar panels?
- Yes, if the panel is designed for both. The generator connects through a listed transfer switch or interlock, and the solar backfeed stays separated from it. We design the two together.
- Do you sell generators?
- No. We install the inlet and the listed transfer switch or interlock that connects a portable generator you own, typically $900–$2,500. We do not sell generators or do fuel work.
- Which is cheaper, a battery or a generator hookup?
- Up front, the generator hookup: typically $900–$2,500 plus the generator you buy. Whole-home battery integration typically runs $6,000–$15,000+. The battery works every day and needs no fuel; the generator only works in outages.
- Is a battery safer than a generator?
- A battery has no combustion exhaust, which removes the carbon monoxide risk that makes Ready.gov warn to run generators only outdoors. Both still need a listed, code-compliant connection to the panel.
Next step
Pick the backup plan with an electrician
We look at your panel and your outage needs, then quote solar, a battery, a generator hookup, or a mix. The quote is free.
Solar energy company
AJ Long Electric Solar
AJ Long Electric
7138 Little River Turnpike #305
Annandale, VA 22003
Serving Annandale, Fairfax County, and Northern Virginia.