Power · Solar
What size solar panel do I need for a 12V fridge? About 100W in good sun.
The panel charges the battery, and the fridge runs from the battery. A panel doesn’t plug straight into the fridge: it goes through a solar regulator (built into many power stations) to the battery. The 100W is for a typical 40–60 L single-zone 12V fridge with 5 good sun hours. For cloudier days with 3 good sun hours, about 160–200W. Worked out from 24 fridges’ official power figures with the same maths as our fridge calculator.
Calculated, not tested by Seekstead. Maker figures checked 6 October 2026.
The short answer
Match the panel to the fridge’s daily use.
- 40–60 L single-zone fridge: about 100W in good sun, 160–200W for cloudier days. The 8 fridges in that size range need 63–99W of panel with 5 good sun hours, or 104–165W with 3.
- Small fridge, up to 30 L: about 100W in good sun, 100–160W for cloudier days.
- Dual-zone fridge freezer, with one side freezing: about 160–300W in good sun, 300–400W for cloudier days. Freezing uses far more power.
- Hot days: allow 30% more. A 40–60 L fridge then needs up to 128W in good sun, so about a 160W panel.
- The battery runs the fridge; the panel refills it. These sizes put back what the fridge uses on a day with that much sun. The battery carries you through nights and cloudy spells. Our 100Ah lithium run time guide shows how long that lasts.
By fridge
Panel size for 24 fridges.
The smallest of the common panel sizes (100, 160, 200, 300 and 400W) that puts back each fridge’s daily use, from the maker’s own figure, with no extra for hot days. Makers test at different temperatures, shown for each fridge.
| Fridge | Size | Uses per day | 5 good sun hours | 3 good sun hours | Maker’s test conditions | Source |
|---|---|---|---|---|---|---|
| Dometic CFF 12 | 13 L | 11.5 Ah | 100W (needs 39W) | 100W (needs 66W) | ambient 32°C, internal 4°C, 12 V DC | Dometic ↗ |
| Bushman Roadie SC15 | 15 L | 13.9 Ah | 100W (needs 48W) | 100W (needs 80W) | 25º ambient, 4º fridge, 12V system | Bushman ↗ |
| Dometic CFF 18 | 19 L | 15.8 Ah | 100W (needs 54W) | 100W (needs 91W) | ambient 32°C, internal 4°C, 12 V DC | Dometic ↗ |
| Dometic CFX5 25 | 25 L | 18.5 Ah | 100W (needs 63W) | 160W (needs 106W) | ambient 32°C, internal 4°C, 12 V DC | Dometic ↗ |
| myCOOLMAN 30L Transporter | 30 L | 19.2 Ah | 100W (needs 66W) | 160W (needs 110W) | average per hour; DC12V set at 5°C, 32°C ambient | myCOOLMAN ↗ |
| Dometic CFX5 35 | 36 L | 18.5 Ah | 100W (needs 63W) | 160W (needs 106W) | ambient 32°C, internal 4°C, 12 V DC | Dometic ↗ |
| Dometic CFX2 37 | 37 L | 18.7 Ah | 100W (needs 64W) | 160W (needs 107W) | ambient 32°C, internal 4°C, 12 V DC | Dometic ↗ |
| Evakool 40L Platinum Drawer | 40 L | 28.8 Ah | 100W (needs 99W) | 200W (needs 165W) | average over 24 hours at 32ºC, set on 2ºC | Evakool ↗ |
| Dometic CFF 45 | 44 L | 20.9 Ah | 100W (needs 72W) | 160W (needs 119W) | ambient 32°C, internal 4°C, 12 V DC | Dometic ↗ |
| myCOOLMAN 44L single zone | 44 L | 19.2 Ah | 100W (needs 66W) | 160W (needs 110W) | average per hour; DC12V set at 5°C, 32°C ambient | myCOOLMAN ↗ |
| Dometic CFX2 45 | 45 L | 20.6 Ah | 100W (needs 71W) | 160W (needs 118W) | ambient 32°C, internal 4°C, 12 V DC | Dometic ↗ |
| Dometic CFX5 45 | 46 L | 18.2 Ah | 100W (needs 63W) | 160W (needs 104W) | ambient 32°C, internal 4°C, 12 V DC | Dometic ↗ |
| Dometic CFX5 55 | 55 L | 20.9 Ah | 100W (needs 72W) | 160W (needs 119W) | ambient 32°C, internal 4°C, 12 V DC | Dometic ↗ |
| Dometic CFX5 55IM (icemaker on) | 55 L | 29 Ah | 100W (needs 100W) | 200W (needs 166W) | Ambient 32°C, internal 4°C, icemaker on (maintenance) | Dometic ↗ |
| Dometic CFX2 57 | 57 L | 21.4 Ah | 100W (needs 73W) | 160W (needs 122W) | ambient 32°C, internal 4°C, 12 V DC | Dometic ↗ |
| myCOOLMAN 60L single zone | 60 L | 19.2 Ah | 100W (needs 66W) | 160W (needs 110W) | average per hour; DC12V set at 5°C, 32°C ambient | myCOOLMAN ↗ |
| myCOOLMAN 105L single zone | 105 L | 33.6 Ah | 160W (needs 115W) | 200W (needs 192W) | average per hour; DC12V set at 5°C, 32°C ambient | myCOOLMAN ↗ |
| Dometic CFF50LPDZ | 50 L dual-zone | 42 Ah | 160W (needs 144W) | 300W (needs 240W) | 4°C fridge, −15°C freezer, 32°C ambient | Dometic ↗ |
| Evakool 50L Down Under II | 50 L dual-zone | 43.2 Ah | 160W (needs 148W) | 300W (needs 247W) | average over 24 hours at 32°C, one zone at 2°C, one at −16°C | Evakool ↗ |
| Evakool 65L Down Under II | 65 L dual-zone | 45.6 Ah | 160W (needs 156W) | 300W (needs 261W) | average over 24 hours at 32°C, one zone at 2°C, one at −16°C | Evakool ↗ |
| Dometic CFF 70DZ | 70 L dual-zone | 69.6 Ah | 300W (needs 239W) | 400W (needs 398W) | 4°C fridge, −15°C freezer, 32°C ambient | Dometic ↗ |
| Dometic CFX5 75DZ | 75 L dual-zone | 58.8 Ah | 300W (needs 202W) | 400W (needs 336W) | 4°C large zone, −15°C small zone, 32°C ambient | Dometic ↗ |
| Evakool 80L Down Under II | 80 L dual-zone | 48 Ah | 200W (needs 165W) | 300W (needs 274W) | average over 24 hours at 32°C, one zone at 2°C, one at −16°C | Evakool ↗ |
| Dometic CFX5 95DZ | 94 L dual-zone | 67.9 Ah | 300W (needs 233W) | 400W (needs 388W) | 4°C large zone, −15°C small zone, 32°C ambient | Dometic ↗ |
What a panel puts back
Amp-hours back each day.
Panel watts × good sun hours × 0.7 (for real-world losses) ÷ 12 volts. A typical 40–60 L fridge uses 18.2–28.8 Ah a day.
| Panel or blanket | 5 good sun hours | 3 good sun hours |
|---|---|---|
| 100W | about 29.2 Ah | about 17.5 Ah |
| 160W | about 46.7 Ah | about 28 Ah |
| 200W | about 58.3 Ah | about 35 Ah |
| 300W | about 87.5 Ah | about 52.5 Ah |
| 400W | about 116.7 Ah | about 70 Ah |
Good sun hours vary with season, location and shade, and cloudy days can drop to a fraction of these.
Keep going
Related on Seekstead.
Calculator
12V fridge battery calculator
Pick your fridge, battery and solar for your own run time.
Open the calculator →
Guide
How long will a 100Ah lithium run a fridge?
Run times for 24 fridges, lithium and AGM.
Read more →Gear
Kings 200W solar blanket
How much it puts back for a fridge.
Take a look →Gear
Kings 100Ah lithium battery
Specs and fridge run times for this battery.
Take a look →
Our setup
My setup: a real camp power build
The 240Ah battery, solar and Starlink setup behind these pages.
Read more →How we work it out
From published figures.
Panel watts needed = the fridge’s daily use (Ah per 24 hours at 12V) × 12 ÷ (good sun hours × 0.7). The 0.7 allows for real-world losses (heat, angle, cabling and the charge controller), the same assumption as our fridge calculator. Each fridge’s daily use comes from its maker’s official page, linked in the table; where a maker gives amps per hour, we multiply by 24. These are theoretical estimates, not tests: weather, shade, panel angle and how the fridge is used all change the real result.
Seekstead doesn’t earn from the maker links on this page. Our own product pages may contain referral links: how they work.