How Do I Power A Fridge When Camping?
Keeping food and drink cool on a camping trip can be a little more complicated if you’re using more than an eski full of ice, so when it comes to powering a car fridge we’ve put together a step by step guide to everything you need to know from calculating a car fridge’s power consumption and choosing the right battery, to using and recharging your battery when camping.
STEP 1: DETERMINE FRIDGE SPECIFICATIONS.
Car fridges aren’t all the same when it comes to the power they consume. There are numerous factors that can affect how much power a fridge is going to consume such as the fridge size and how much you put in it. You also need to consider the ambient temperature and how many times the fridge is going to be opened and closed as this will affect how much power your fridge will consume. All reputable fridges on the market will have the power consumption listed on their packaging or user manual so it is important to know how much power you are going to need so your food and drinks stay cold.
STEP 2: CALCULATING FRIDGE POWER CONSUMPTION
Now to find the right equipment to power a fridge when camping, we have to work out the power consumption of that fridge. Fridges run through a cooling cycle; meaning that they will turn on to cool down the fridges contents, then once it hits a set temperature it will turn off. It will then turn on again when the fridges insides heat up past a certain point and cool it back down. When calculating the power consumption of a fridge, we use a 50/50 on/off cycle ratio to work out the total consumption.
Let’s looks at how much power a fridge will consume over 24 hours at 100% cycling. You will first need to discover how many Amps (on average) the fridge uses per hour over the course of the whole day. Then, convert that measurement into Watts. This means multiplying the Amperage by 12 (12 Volts) to uncover the hourly Wattage. This hourly Wattage then needs to be multiplied by 24 (24 hours) to calculate how many Watts the fridge will consume in a full day. That final figure will determine the kind of battery size you will need. Using these calculations, under normal usage it can be estimated that a 50 Litre 12V Fridge will consume an average of 93.6 watts per hour (or 2246.4 watts over 24 hours). If you want to find out the power consumption of the fridge at 50% cycling, you would merely half that final value again, so the 50L fridge would use 1132.2 Watts over 24 hours).
STEP 3: POWERING FRIDGE WITH POWER SOURCE
With most batteries and solar generators, such as the Goal Zero Yeti 400, powering a fridge when camping merely requires plugging the fridge straight into the 12V (or 240v inverter) outlet.
In the table below is an example of the differing power consumptions of popular car fridges, and the calculations required for run times. (note real data taken from the product user manuals)
|Fridge 1 (40L)||Fridge 2 (50L)|
|Watts per hour||30 Watts||93.6 Watts|
|Watts per 24 Hours||720 Watts||2246.6 Watts|
|100% Cycling Time for Yeti400||13.3 Hours||4.3 Hours|
|50% Cycling for Yeti400||26 Hours||8.5 Hours|
|Yeti400 Run Time||13.3 – 26 Hours||4.3 – 8.5 Hours|
As you can see with the two examples the fridge consumption varies a lot and, especially in summer, the fridge takes a long time to cool down. Calculating the 100% cycling times requires the wattage output of the battery to be divided by the watts per hour that the fridge is using. If you want the 50% cycling time, you would then go on to half that value.
A warm fridge with warm drinks means you would be using your battery or solar generator much quicker as you would expect it to have a 100% cycle or run time. Starting with cools drinks and cool food and keeping the fridge stored in a cool location will considerably improve your runtimes, as the table displays. This simply means you would need to be conscious of these run times, and from them, when your battery or solar generator would require recharging to keep your car fridge running.
Something you may also like to consider if you are going to be needing a fridge for a few days is how you are going to charge the battery enough to keep it running. A rechargeable battery or solar generator is your best bet in this instance. The Yeti 400 solar generator can be recharged from the wall, a vehicle or solar panel.
STEP 4: CHARGING POWER SOURCE
Let’s take a look at the solar charging option and work out what size solar panel we need to keep up with the fridges demands. There is only 8 hours of good useable sunlight in a day, so using the specifications calculated in Step 2 from the 40L car fridge cycling at 50%, we need to make up 360 Watts of power over 8 hours in order to keep the fridge running day and night. This would mean we need to collect 45 watts per hour. Our Boulder 90 or Nomad 100 panel can collect more than this required amount of power so either would be a perfect solution.
If you have any further questions regarding battery requirements, or understanding your charging capabilities, please call us on (07) 3245 6190 or via our contact form to get in touch with our tech team. If you’re looking to buy a Goal Zero Solar Generator you can find your local retailer here.