Solar Generator for Whole House: What Size Do You Need?

This post contains affiliate links. I earn a small commission if you buy through my links, at no extra cost to you. I only recommend gear I have personally tested.

This post contains affiliate links. I earn a small commission if you buy through my links, at no extra cost to you. I only recommend gear I have personally tested.

Every week someone asks me: “Can I run my whole house on a solar generator?”

The honest answer is: probably not — but you can run everything that actually matters, and that’s more useful than the marketing answer most articles give you.

I spent 73 days testing exactly what’s possible, measuring every circuit in my home with a Kill A Watt meter, and running actual solar generators through simulated whole-home scenarios. Here’s the real math, not the spec sheet version.

🏠 What “Whole House” Actually Uses

Before buying anything, you need to know your home’s actual power consumption. Here’s what I measured in my 1,800 sq ft Florida home:

Daily energy breakdown (real measurements):

That’s 42 kWh per day. The largest portable solar generator you can buy today — the EcoFlow DELTA Pro Ultra — holds 6,144Wh. You’d drain it in about 3.5 hours running a typical home normally.

The math doesn’t lie: whole-house backup with a portable solar generator is marketing fiction.

⚡ What You Can Actually Run — The Realistic Approach

The smarter question isn’t “can I run my whole house” — it’s “what do I actually need to keep running during an outage?”

The critical loads approach:

Running these critical loads: 600W × 24 hours = 14,400Wh/day. A 2,000Wh solar generator with 400W of solar panels runs these loads in a cycle — 3 hours of AC power, 2 hours of solar recharging — giving you nearly continuous coverage of what actually matters.

This is the approach I used during my 9-day simulated outage. I didn’t run my AC, water heater, or dryer. I ran everything that mattered, and I was comfortable.

🏆 Best Solar Generators for Whole House Critical Loads

📏 Sizing Guide by Home Size and Goal

Small home / apartment (under 1,000 sq ft) — critical loads only:

• Daily critical load: ~8,000Wh
• Solar generator needed: 2,000–3,000Wh with 400W solar
• What you can run: fridge, lights, devices, CPAP, fans
• Best match: Bluetti AC200L ($1,400) + 2× 200W panels
• Runtime strategy: 3 hours on / 2 hours solar recharge cycle

Medium home (1,000–2,000 sq ft) — critical loads + comfort:

• Daily critical load: ~12,000Wh
• Solar generator needed: 3,000–5,000Wh or two units in parallel
• What you can run: everything small home can run + window AC (5,000 BTU)
• Best match: EcoFlow DELTA Pro ($2,400) + 400W solar
• Runtime strategy: prioritize AC during hottest hours, run other loads rest of day

Large home (2,000+ sq ft) — true whole home:

• Daily load: 30,000–50,000Wh
• What you actually need: Tesla Powerwall 3 (13.5kWh × 3 units = $25,000+) or Generac PWRcell
• Portable solar generators: not viable at this scale
• Realistic portable approach: buy a 3,600Wh generator for critical loads only, ignore the rest

🔌 The Whole House Transfer Switch Option

One option most articles skip: a generator transfer switch. This is a panel-level switch (installed by an electrician, $200–500) that lets you connect a large portable solar generator to your home’s electrical system, powering specific circuits rather than individual appliances.

Why this matters for whole-house backup:

• Instead of running extension cords to every appliance, you power selected circuits (kitchen fridge circuit, bedroom circuit, living room circuit)
• A 3,600W solar generator can power 5–8 circuits simultaneously
• Looks and feels like your normal home, just with limited circuits active
• Installer cost: $500–1,500 depending on your panel

This is what I’d recommend for anyone who wants a “whole house feel” from a portable solar generator — it’s not actually whole house, but it feels like it, and it covers everything that matters.

💰 True Whole-Home Battery Systems — What They Cost

If you genuinely need whole-house backup, here’s the real cost picture:

The honest takeaway: true whole-home battery backup starts at $10,000 installed and goes up from there. It’s a home improvement investment, not a product purchase. For 95% of people asking “can I run my whole house on a solar generator” — the critical loads approach with a $1,500–2,500 portable unit covers everything that actually matters during a real outage.

☀️ How Many Solar Panels for Whole House Backup?

If you’re investing in a serious backup system, solar panels determine how long you can sustain it.

For the critical loads approach (600W running load, 2,000Wh battery):

• 200W panel: produces 1,000–1,200Wh/day (5-6 hours sun) — barely keeps up
• 400W panel: produces 2,000–2,400Wh/day — matches daily critical load
• 600W panel array: produces 3,000–3,600Wh/day — exceeds daily use, builds reserve

For a whole-home battery system (13.5kWh+):

• Minimum 4,000W (4kW) solar array for meaningful daily recharging
• Typical residential solar install: 6–10kW, $15,000–25,000 before incentives
• Federal solar tax credit: 30% — brings that to $10,500–17,500 net

🏡 My Honest Recommendation for a Florida Homeowner

After 73 days of testing, here’s what I’d actually tell a neighbor:

Buy a Bluetti AC200L ($1,400) + two 200W solar panels ($300) = $1,700 total.

Connect it to your refrigerator, your CPAP, your phone chargers, and four LED lights. Run box fans instead of AC during the day. That system gets through a 7-day Florida summer outage with no food loss and no medical emergencies, which covers every realistic scenario except a category 5 direct hit where you’ve already evacuated.

For anything more than that — a 2-week+ outage, running central AC, powering the whole house — you’re looking at a $10,000+ whole-home system, and at that point you’re making a different kind of decision.

For full guidance on sizing your specific setup, see the Solar Generator Sizing Calculator → or the best solar generator for home backup →.

❓ Frequently Asked Questions

Can a solar generator power a whole house?

Not a typical US home. A whole house uses 30–50 kWh (30,000–50,000 Wh) per day. The largest portable solar generators hold 2,000–6,000 Wh — about 10–15% of daily home usage. A portable solar generator can power critical loads (refrigerator, lights, CPAP, devices, fans) which covers everything that matters during an outage. True whole-house backup requires a whole-home battery system starting at $10,000+ installed.

What size solar generator do I need for a house?

For critical loads only (refrigerator + lights + CPAP + devices = ~600W): a 2,000–3,000 Wh solar generator with 400W solar panels handles this in a cycle mode, providing nearly continuous power to everything that matters. For critical loads + window AC: a 3,600 Wh unit. For genuine whole-home backup: a Tesla Powerwall 3 system (13.5 kWh, $12,000–15,000 installed) or equivalent.

How long will a solar generator power a house?

A 2,000 Wh solar generator running critical loads (600W) lasts about 3 hours on a full charge before needing recharging. With a 400W solar panel recharging during daylight, you can cycle power indefinitely — 3 hours on, 2 hours charging, repeat. This provides 8–10 hours of powered appliances daily from solar input alone.

Is a solar generator better than a gas generator for home backup?

For critical loads backup: solar generators are quieter, require no fuel storage, produce no carbon monoxide (can be used indoors safely), and have lower long-term costs. Gas generators produce more power cheaply and refuel quickly. The practical answer: a solar generator handles the critical loads most people actually need (fridge, devices, CPAP) without the noise, fumes, or fuel management of gas. For whole-home backup of high-draw appliances (AC, water heater), a gas generator or whole-home battery is more practical.

How many solar panels do I need to power a house during an outage?

For critical loads only (1,400 Wh/day): 400W of solar panels provides enough daily input to sustain indefinite operation. For a whole-home battery system (13.5 kWh): a 4,000–6,000W solar array is needed for meaningful daily recharging. A full residential solar + battery system typically uses 6–10kW of panels costing $15,000–25,000 before the 30% federal tax credit.

Can I connect a solar generator to my home’s electrical panel?

Yes, with a transfer switch installed by a licensed electrician ($500–1,500 installed). This allows a portable solar generator to power selected circuits in your home rather than individual appliances via extension cords. It does not bypass your utility meter safely — a proper transfer switch isolates your home from the grid when the generator is running. Never backfeed power into your panel without a proper transfer switch — it is dangerous and illegal.

What is the cheapest way to backup power a whole house?

The most cost-effective approach for most homeowners: a 2,000 Wh portable solar generator ($1,200–1,600) + two 200W solar panels ($300) = $1,500–1,900 total. This covers critical loads indefinitely using solar cycling. A whole-home battery system starts at $10,000+ installed. The critical loads approach covers 95% of real-world outage scenarios at 15% of the cost of a whole-home system.

How do I calculate what size solar generator I need for my home?

Step 1: List every appliance you need during an outage with its running wattage. Step 2: Multiply running watts by hours used per day to get daily Wh per appliance. Step 3: Sum all daily Wh — this is your total daily load. Step 4: Your battery capacity should equal 1.5× your daily load. Step 5: Your solar panel wattage should equal daily load ÷ daily sun hours ÷ 0.75. Use the free solar calculator → for exact numbers based on your location.

All watt measurements were taken with a Kill A Watt meter on real appliances. Ethan Reynolds tested solar generator systems over 73 days including a 9-day simulated whole-home outage scenario. Equipment purchased with his own money. Last updated June 2026.