Anyone know if a 200Ah lithium battery will run a small chest freezer overnight?

Running a small chest freezer off my static caravan's battery bank and wondering if the maths actually works out in practice.

I've got a single 200Ah 12V Fogstar Drift lithium (so roughly 2.4kWh usable), and I want to keep a small chest freezer — think Inventor or SIA, around 100L — running overnight when solar input drops off. Probably 10–12 hours without meaningful charge coming in.

From what I can find, a small chest freezer draws somewhere between 60–100W when the compressor kicks in, but obviously it cycles on and off. Rough estimates I've seen suggest maybe 0.5–1kWh per 24 hours depending on ambient temp and how full it is.

So in theory overnight shouldn't be a problem — but that's where I'm nervous, because theory and reality seem to diverge quite a bit with freezers.

A few specific questions:

• Does ambient temperature massively change the consumption? My caravan can get warm in summer so I'm wondering if I'm being optimistic
• Is there a risk of the compressor surge tripping a Victron MultiPlus at startup? Mine's a 12/1200
• Has anyone actually measured overnight draw on a similar setup with a clamp meter or Victron Cerbo rather than just estimating?

Don't want to wake up to a warm freezer and ruined food, but also don't want to go buying a second battery if one will genuinely cope. Any real-world experience appreciated.

@TelHall the maths roughly works but it's tight. Small chest freezers typically pull 100-150W when the compressor's running but only cycle maybe 20-30% of the time in a cool environment — so real-world draw is often 1-1.5kWh per 24hrs.

Problem is "overnight" isn't the whole picture. If your static is in direct sun all day and that freezer's working harder, the duty cycle climbs fast.

I ran a similar setup on my van before upgrading — a single 200Ah Fogstar was fine in winter, genuinely sweaty in August.

Main thing to check: what's actually your ambient temperature? Stick a plug-in energy monitor on it for 24 hours before trusting anyone's numbers including mine. Costs a fiver from Amazon and saves a lot of guessing.

@TelHall done exactly this in my motorhome — the killer detail nobody mentions is ambient temperature: a chest freezer in a warm static caravan works its compressor far harder than one sitting in a cool outhouse, so your duty cycle could creep from 30% up to 50%+ on a warm night, which turns "tight but fine" into "flat battery by 4am."

Stick a Victron SmartShunt on it for a week and log actual consumption before committing — real-world data beats back-of-envelope every time.

Also worth checking your Fogstar's low-temperature cutoff if your static caravan gets properly cold overnight; lithiums get unhappy drawing hard current below about 5°C.

@TelHall the compressor duty cycle is the wildcard nobody pins down until they've actually logged it — stick a Shelly plug on it for 48 hours and you'll get real consumption figures rather than guessing from nameplate wattage, which is essentially fiction.

My motorhome Fogstar setup taught me that a "40L chest freezer" can swing between 0.4kWh and 1.2kWh per 24hrs depending on how full it is (thermal mass is your mate — pack it with frozen water bottles). Your 2.4kWh usable is theoretically enough but leaves zero headroom for a bad night, and @MarineGeoff's ambient point is dead right — a static caravan in summer is basically a greenhouse.

Honestly I'd want a second 200Ah before sleeping soundly on it.

@TelHall lived this exact scenario on my narrowboat for two summers running. The maths works, but the starting surge nearly caught me out — my little chest freezer pulls a spike of 4-5x running watts when the compressor kicks in, which stressed my inverter something rotten until I upgraded it.

Also worth knowing: chest freezers are brilliant candidates for off-grid because a well-stocked, well-sealed one holds temperature for ages between compressor cycles. Pre-cool it on shore power before you disconnect and your duty cycle drops noticeably.

@FormerCop is right about logging it first — I ran mine through a Victron BMV-712 for a week before trusting my sums. Gut feel and spreadsheets only tell half the story; real consumption data tells the rest.