What Size Solar Generator Do I Need?

A full-size refrigerator draws 100–250 W running with a 600–1,200 W startup surge. You need a generator that can handle the surge — at least 1,200 W peak output — and enough capacity to cover the fridge's daily consumption. A typical fridge uses ~1,200–2,000 Wh per day depending on size and efficiency. For a fridge alone, a 1,500–2,000 Wh unit works for about a day. For fridge + other essentials, go with 3,000+ Wh.

A CPAP without a humidifier draws 30–60 W per night — a 300 Wh unit (like the Anker SOLIX C300 DC) gives you 5–10 nights. With a humidifier, consumption jumps to 60–100 W per night, so a 500–1,000 Wh unit is safer. If you also need to run a fan, lights, or phone charging alongside the CPAP, go with 1,000+ Wh. Some CPAP users also need a pure sine wave inverter — all modern solar generators use pure sine wave, so this isn't a concern with any of the units recommended here.

For weekend car camping with a mini fridge, phone charging, lights, and a laptop, a 500–1,500 Wh unit is the sweet spot. The Jackery Explorer 1000 V2 (1,070 Wh) is our top pick for this use case — it's 20.7 lbs, powers a mini fridge for 6–10 hours, and has enough overhead for charging multiple devices. For backpacking or tent camping where weight matters more than capacity, look at the under-500 Wh tier (288 Wh units like the Anker SOLIX C300 DC at 7.9 lbs).

Most RV setups — 12 V fridge, LED lights, water pump, TV, laptop charging — consume 1,000–2,000 Wh per day. The 1,500–3,000 Wh tier is the right fit for 1–2 days of autonomy. If you boondock (no hookups) for extended periods, pair the generator with 400–800 W of portable solar panels. For larger RVs with residential refrigerators, air conditioning, or electric cooking, step up to the 3,000–5,000 Wh tier or supplement with a gas generator for AC loads.

For essential circuits only — fridge, router, a few lights, and device charging — a 1,500–3,000 Wh unit works for up to 24 hours. For partial home backup that includes a sump pump, well pump, or furnace fan, go with 3,000–5,000 Wh. For whole-home backup covering multiple appliance circuits through a transfer switch, look at the 5,000–10,000 Wh tier or even 10,000 Wh+ if you want multi-day autonomy without solar recharging. Use the 5-step method above to calculate your exact needs.

It depends on your generator's solar input rating and your daily consumption. A 1,000 Wh unit with a 200 W solar input can fully recharge from dead in about 5 hours of peak sun (200 W × 5 h = 1,000 Wh). A good rule of thumb: match your solar array wattage to 20–30% of your battery capacity. So for a 1,000 Wh unit, 200–300 W of solar panels is a practical minimum. For a 5,000 Wh system, aim for 1,000–1,500 W. Most generators limit solar input, so check the spec before buying panels — oversized panels won't damage the unit but won't charge faster than the max input allows.

Not directly — you can't plug one generator into another. However, you can use both in a complementary setup: run the gas generator during the day to power heavy loads and recharge your solar generator's battery, then switch to the silent solar generator at night for lights, router, and CPAP. This hybrid approach gives you the runtime of gas with the quiet, emission-free overnight experience of solar. Some advanced setups use a transfer switch to select between generator inputs, but never physically connect two generators to the same circuit simultaneously.

Compare the generator's peak/surge output (usually listed in the specs) to the appliance's surge watts. Most fridge compressors surge to 600–1,200 W; sump pumps can surge to 1,300–2,500 W; well pumps may surge to 2,000–4,000 W or more. If the generator's surge rating is below the appliance's surge, it won't start. Some generators list peak output for only 10–100 ms, which may not be long enough for some motor loads — a 20–30% buffer above the appliance surge is a safer bet. If in doubt, choose a higher wattage unit or test with a kill-a-watt meter before relying on it in an emergency.