Cabin power that survives January
Cabin power systems fail in winter, not summer. PowerLab sizes for the worst-week you’ll actually see — peak-sun-hours, days of autonomy, and cold-weather battery derating all baked in.
Winter-first sizing
Uses worst-case peak-sun-hours, not annual average. December and February are what break cabins.
Cold-weather derate
LiFePO4 can’t charge below 0°C. We factor that into usable capacity automatically.
Generator as backup
Model solar + battery + generator together. Size the gen for realistic cloudy-stretch coverage, not everything-at-once.
Realistic cabin loads
Well pump, fridge, mini-split, chest freezer, LED lights, Starlink, electric bike charger — all pre-modeled.
Typical loads we already model
These are realistic watt draws and duty cycles pulled from the PowerLab appliance catalog. When you start a design, you pick from this catalog and customize \u2014 nothing to re-type.
| Load | Watts | Hrs/day | Wh/day |
|---|---|---|---|
| Refrigerator (full-size) | 150 | 8 | 1,200 |
| Well pump (1/2 HP) | 750 | 0.5 | 375 |
| Mini-split heat pump (12k BTU) | 900 | 6 | 5,400 |
| Chest freezer | 120 | 8 | 960 |
| LED lights (6 rooms) | 40 | 5 | 200 |
| Starlink + router | 50 | 12 | 600 |
| Ceiling fan | 60 | 4 | 240 |
| Sample total | 8,975 Wh/day |
Typical real-world band for this niche: 3,000\u20138,000 Wh/day (midpoint 5,500). Your actual number depends on your gear and how you use it; PowerLab calculates it exactly.
Ask these once your design is loaded
PowerLab Co-Pilot sees your exact design and can answer questions in plain English. Starter prompts for this niche:
- \u203aWill my battery bank survive 4 cloudy days in February?
- \u203aWhat size generator should I get to cover worst-case?
- \u203aIs my well pump peak draw within my inverter’s surge rating?
Frequently asked
How many solar panels do I need for an off-grid cabin?
For weekend use with LED lights + fridge, ~400–800W. For full-time winter living with a heat pump, 2000–4000W plus generator backup. PowerLab sizes to your actual loads and region — not YouTube averages.
Do I need a generator?
Most cabins in cold climates want one. Even with a big solar + battery system, a 4-day January cloudy stretch will drain any sensible bank. A small propane gen covers that gap cheaply.
Can I run a well pump off a battery system?
Yes — but the starting surge is 3× running current, and pumps at 2HP+ push the limits of most off-grid inverters. PowerLab’s inverter sizer warns you when your peak draw is too close to the inverter’s surge rating.
Design yours in the next 10 minutes
Free tier gets you load + battery + solar sizing for up to 3 designs. No credit card required. Upgrade when you need the Co-Pilot, live BMS monitoring (Victron live today), or permit-ready PDFs.
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