Hey everyone! I'm trying to figure out how much battery I need to run my 120v AC refrigerator. The sticker on it says it draws 7.10 amps, but I'm guessing that's just the startup current for the compressor. Instead of physically moving my heavy fridge (which just messed up the flooring), is there any way to roughly estimate how many watt-hours it uses in a day? Just to clarify, I'm not factoring in solar or other power sources right now—I'm just focused on finding out how much battery I'll need for the runtime.
3 Answers
Fridge consumption can vary greatly! In my experience, it can be as low as 0.5 kWh per day if the door stays closed, but then spikes to about 3 kWh after grocery runs and frequent openings. Don't forget, there's also the inverter's power draw to consider. Typically, an inverter will use around 20-30W just to operate, so plan for that too. In a pinch, you could run the fridge for short periods while keeping the door shut to conserve energy.
An efficient estimate is to use specs from your fridge's EnergyGuide label, usually found on the back. It can show yearly electricity usage, which you can divide by 365 for an average daily use. For inverter sizing, you’d want between a 5 to 10 kWh battery to keep it running effectively during power outages. Also, if it has extra features like a defrost cycle, consider shutting that off to save some power.
To get a good ballpark for your fridge's daily usage, it really depends on how often it's running. Since you can’t measure it right now, a rough estimate would be about 1 to 2 kWh per day, just to be safe—so erring on the side of 2 kWh gives you some breathing room. Ideally, you’d want to check that with a meter later when possible, but that's a decent way to gauge it for now.
Exactly! Keeping the door closed is vital. I’ve got a similar situation, and every time the door opens, it just wastes power trying to cool down that warm air again. Every bit counts!