Who This Is For
If the grid just went down—or you're staring at a forecast that says it will—and you're wondering if solar + battery can save you, this checklist is for you. I've coordinated over 200 emergency solar and battery installations in my 8 years with Vivint Solar. Most of these were rush jobs: critical infrastructure for medical devices, server rooms, or homes with elderly residents who can't lose heat or AC.
This isn't a generic "how solar works" guide. This is the exact process I walk through when a client calls at 4 PM Friday needing power by Saturday morning. There are 5 steps, and skipping one has cost people their backup power—or thousands in extra fees. Let's go.
Step 1: Assess Your Critical Loads (Don't Guess)
Don't assume you know how much power you need. I can't tell you how many times someone has said, "I just need the fridge and a few lights." Then they find out their fridge draws 800W and their CPAP machine needs clean sine wave power. That changes the equipment list.
Here's what I ask every client:
- Medical/life-safety: Do you have oxygen concentrators, CPAP, insulin refrigeration? These are non-negotiable.
- Comfort: Fridge, freezer, well pump, sump pump, furnace fan. Gas furnace still needs electricity for the blower.
- Work/security: Modem/router, laptop, security cameras, phone charging.
- Indulgence: TV, gaming console, coffee maker. Nice to have, but we size for the essentials first.
Make a list. Right now. Include wattages (they're printed on the device or online). Total them up. That's your minimum continuous load. Multiply by the hours you expect to run on battery alone (typically 12-24 hours for a storm). That's your battery capacity target.
Step 2: Pick the Right Battery (Not All Are Equal)
This is where most people mess up. They assume any "solar generator" or home battery will work. It won't. The difference between a unit that keeps your lights on and a brick that sits in the garage is in the details.
For emergency backup with Vivint Solar, we typically recommend:
- Vivint Solar + LG Chem RESU: 9.8 kWh capacity, enough to run a fridge + lights + router + one medical device for 12-18 hours. Can be paired with solar panels for daytime recharge.
- Vivint Solar + Tesla Powerwall (compatible): 13.5 kWh, more headroom. We can integrate Powerwall with Vivint Solar systems, but it's not our default; we've done it for clients with existing Powerwalls who want to add solar.
- Portable "solar generators" (Jackery, Bluetti, EcoFlow): Great for small loads (phones, lights, CPAP), but don't expect them to run a fridge overnight. A 1 kWh unit will run a mini-fridge for 6-8 hours max. Useful as a supplement, not a primary backup.
Critical detail: If you have a well pump, your battery needs to handle a startup surge of 3-5x the running watts. Many off-the-shelf units can't. We've had clients blow their inverters because they plugged in a well pump without checking surge capacity.
"In 2023, a client called on a Friday at 5 PM—their power was out, and they had a sump pump flooding their basement. Their existing solar generator couldn't handle the startup surge. We had a crew there by Saturday noon with a purpose-built battery system. But they could have avoided the panic if we'd sized it right in the first place."
Step 3: Confirm Timeline (and Overestimate It)
This is the hardest part. Solar + battery installations are not same-day for most systems. Here's what I tell clients:
- Portable solar generator (Jackery/BLUETTI): Available for same-day pickup (Amazon, Best Buy). Can be charging while you drive home.
- Vivint Solar battery + solar panels: Typical installation is 2-4 weeks from design to permit to install. In an emergency? We can sometimes expedite to 3-5 business days if the city has express permitting. I've done same-week for critical medical needs exactly three times in 8 years—and that required the stars to align on permits, crew availability, and equipment stock.
- Solar-only (no battery): Installation is 3-5 days for the panels + inverter, but the system won't run during a blackout without a battery. Many people don't realize this.
My advice: If the power is out now, buy a portable generator or solar generator for immediate needs, and then install the full system for long-term coverage. Don't wait for the perfect permanent solution while your freezer defrosts.
Step 4: Understand the Financials (Don't Be Upsold)
Emergency situations bring out the best—and worst—in companies. Here's what I see:
- Solar generators (Jackery, etc.): $500 to $3,000 for 300Wh to 2kWh. No tax credits. Simple. Good for temporary power.
- Full solar + battery: $15,000 to $30,000 before incentives. Federal ITC (30% tax credit) applies if you install in 2025. Some states add rebates (CA: $0.25/Wh, NY: $500-$1,000).
- Battery-only (no solar): $10,000-$18,000. Still gets the 30% tax credit if paired with an existing solar system.
Red flag to watch for: A company that pushes you into a $30,000 system when your real need is $1,200 portable backup. I've had clients who were panicking during wildfire season and almost signed contracts for full solar+battery that wouldn't be installed for 6 weeks. That's irresponsible. A good salesperson will assess your timeline, not your fear.
One thing I wish I'd tracked more carefully: how often clients who bought portable backup in a rush ended up buying full solar later anyway. Anecdotally? Maybe 60% upgrade within 2 years. The portable unit becomes camping gear. The permanent system does the real work.
"Had two hours to decide before a vendor's deadline for expedited permitting. Normally I'd want 3-5 quotes for a $20k system, but there was no time. Went with our trusted installer—paid $400 in rush fees—but saved $1,200 compared to the next-quickest option. In hindsight, I should have pushed for more time. But with the client's medical equipment at risk, I made the call with incomplete market data."
Step 5: Verify Interconnection & Permits (Yes, Even in an Emergency)
This is the boring part everyone skips. But it's also where the nightmare lives.
If you're connecting a solar + battery system to your home's electrical panel (as most permanent systems do), most cities require a permit and utility interconnection agreement. Doing it without permits can:
- Void your home insurance
- Make it impossible to sell your house
- Result in fines from your utility (I've seen $500-$2,000 fines for unauthorized grid-tied systems)
During an emergency, some cities waive permit fees or expedite review. Call your building department and ask for "disaster-related emergency permitting." Some utilities also have expedited interconnection for storm response. It's not guaranteed, but it's worth the call.
For portable solar generators: No permits needed. Plug the unit into your appliances via extension cords. Pull the manual transfer switch if you're wiring it to your panel (and get a permit for that, please).
Common Mistakes & What to Watch For
After 200+ emergency installations, here's what I see clients get wrong:
- Underestimating startup surge: That fridge draws 150W running, but 800W starting. If your inverter can't handle 800W for 2 seconds, you're in trouble.
- Buying a "solar generator" that's actually a battery + inverter with no solar input: It'll run down in hours unless you plug it into the grid or solar panels. Many people don't realize it needs recharging.
- Assuming grid-tied solar works during blackouts: It doesn't. Grid-tied solar shuts off when the grid goes down to protect utility workers. You need a battery + islanding capability (which most systems have) or a separate generator.
- Not testing the system: I had a client whose battery was installed, but they didn't test it for 3 months. When a storm came, the battery had a firmware bug and wouldn't discharge. We fixed it within 48 hours, but they spent a night in the dark. Test your backup at least once a quarter.
One more thing: If you're considering a full solar + battery system and your power situation is stable (not an emergency), take your time. Get multiple quotes. Compare financing terms. Don't let an emergency sales tactic rush you into a suboptimal system. An informed customer is the best customer—and they make decisions faster when the real emergency comes.