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General => General Discussion => Topic started by: Fizzie on December 15, 2022, 07:36:18 AM

Title: Battery powered fridge
Post by: Fizzie on December 15, 2022, 07:36:18 AM
OK, here's one for all the guru's of power consumption & so on! ;D

Just saw mentioned on another forum: https://www.ryobi.com.au/products/details/18v-one-23l-fridge-freezer-2-x-4-0ah-kit-r18frf142 (https://www.ryobi.com.au/products/details/18v-one-23l-fridge-freezer-2-x-4-0ah-kit-r18frf142)

"This Kit includes 2 x 18V ONE+ 4.0Ah Batteries and an 18V ONE+ 2A Charger ... Depending on the temperature required, these batteries can provide up to 12 hours of runtime* (with a 0 °C temperature setting and 20°C ambient temperature)."

"*18V 4.0Ah battery runtime can vary depending on the mode and temperature setting selected"

Now, of course, 30 minutes is "up to 12 hours", but for the life of me I just can't make 8Ah = 12 hours runtime ???

Oh &
Title: Re: Battery powered fridge
Post by: NZMarkb on December 15, 2022, 09:38:45 AM
I notice they don't show you inside it
23L isn't much at all  ???
Title: Re: Battery powered fridge
Post by: Troopy_03 on December 15, 2022, 09:54:57 AM
OK, here's one for all the guru's of power consumption & so on! ;D

Just saw mentioned on another forum: https://www.ryobi.com.au/products/details/18v-one-23l-fridge-freezer-2-x-4-0ah-kit-r18frf142 (https://www.ryobi.com.au/products/details/18v-one-23l-fridge-freezer-2-x-4-0ah-kit-r18frf142)

"This Kit includes 2 x 18V ONE+ 4.0Ah Batteries and an 18V ONE+ 2A Charger ... Depending on the temperature required, these batteries can provide up to 12 hours of runtime* (with a 0 °C temperature setting and 20°C ambient temperature)."

"*18V 4.0Ah battery runtime can vary depending on the mode and temperature setting selected"

Now, of course, 30 minutes is "up to 12 hours", but for the life of me I just can't make 8Ah = 12 hours runtime ???

Oh &

I don't understand what you mean by the highlighted bit.

But the fridge is rated at 60W, by the manual. What that really means is anyones guess. If they are referring to the actual power consumption when the fridge compressor is running, then that means it draws 3.33A.

So without considering losses and minimum usable voltage of the battery during discharge, one 4Ah battery will power the fridge with the compressor running for 1.2 hours.

How often the compressor runs will determine maximum run time of the fridge. So to get 12 hours from a battery, the compressor will have to run a maximum of 6 minutes per hour.... If you take into consideration inefficiency losses, and how far you can drain down the battery before it is unable to operate the fridge, it will have to be even less than 6 mins/hour...... I'd say their estimate is very optimistic.
Title: Re: Battery powered fridge
Post by: Fizzie on December 15, 2022, 05:02:25 PM
I don't understand what you mean by the highlighted bit.

Oh, just that nasty, cynical person deep down inside, who reads things like that & thinks that if it only works for 30 minutes, then that is "up to" 12 hours, so you can't complain it doesn't do it's job ... ::) >:D
Title: Re: Battery powered fridge
Post by: Troopy_03 on December 15, 2022, 05:59:08 PM
Oh, just that nasty, cynical person deep down inside, who reads things like that & thinks that if it only works for 30 minutes, then that is "up to" 12 hours, so you can't complain it doesn't do it's job ... ::) >:D

haha, gotcha now mate... I was searching the manual for a mention of 30 mins.. had me stuffed...  ;D