# Generators, how many Watts for a fridge?

• 30th December 2013, 12:53 AM
dany2010
Generators, how many Watts for a fridge?
Hi,

With all the power cuts happening round me I'm looking to buy a generator. It's also a new toy for me to play with.

The problem is, looking at currys website the fridge uses 162kWh, surely that's 162,000 watts.

Is my sleep deprivation causing me to miss something here? No home generator could take that. Or is their write up on fridges incorrect?

Many thanks, I'm gonna try and get some sleep now.
• 30th December 2013, 01:39 AM
Jobos
That's the annual estimated consumption but I think you are looking at 100 to 150w for a fridge so about 0.5 amp maybe a little more when it starts
• 30th December 2013, 01:44 AM
dany2010
Thanks Jobos.

Thought it was around that. We used to run a kettle of one and they are like 1500w.

A little 1kw gen looks good to me just for emergencies like fridge and a small tv lol. Or 1.5kw gen could power a heater.
• 30th December 2013, 03:00 AM
plexer
Look at the rating plate for the amperage of the fridge and work it out.

Ben
• 30th December 2013, 10:37 AM
jinnantonnixx
You can't really go by the kWh figure, that's the energy used by the fridge over (presumably) the year, not it's power rating. It's useful for comparing against other fridges. For specifying instantaneous power consumption it's less useful.

The kWh rating is the energy used over time, the watt rating is the power.

Furthermore, a fridge doesn't run all the time, it fluctuates based on its thermostat, so that's another variable.

However, we can make an average calculation if we know the hours in a year (8766) and the kwh rating

P(w) = 162000 / 8766 which gives about 18.5W on average, over the year. The peaks are anyone's guess but it's unlikely to be anywhere near that of another kitchen appliance. You might get by with a car battery and an inverter for a while. A mini-UPS would certainly fit the bill.
• 30th December 2013, 10:55 AM
Oaktech
I wouldn't run a heater from a generator, just because it's not that economical given the price of petrol. It would be more effective to get one of those standalone gas heaters...

Something like this would be useful... Clarke FG3005 2.8kVA Portable Petrol Powered Generator - Machine Mart But bear in mind what comes out of it might be a bit lumpy for delicate electronics, so if you need to run computer equipment from it you might need a UPS to smooth out the lumpy AC.
• 30th December 2013, 12:40 PM
Andrew_C
And please DON'T run the genny indoors. It might seem obvious, but there was a report only over the W/E of several cases of CO poisoning following the pre-xmas power cuts.
• 30th December 2013, 12:55 PM
Oaktech
I've just had a shufty at the applinaces I have lying around at work...

Our mini fridge consumes 200watts startup and 50w continous.

Undercounter fridge with an icebox consumes 1100w startup and 200w continuous.

Our mahoosive fridge/freezer thing in the staffroom consumes 1700w startup and 500w continuous.
• 6th January 2014, 10:37 AM
Marci
Yup - crucial thing with fridges is the startup load which generally lasts for about 3 seconds each time the compressor starts. I have an undercounter fridge with 1200w startup / 110w continuous... My 800w generator simply trips as soon as you plug the fridge in and won't entertain it. Essentially, your generator needs to be rated for greater than that startup pull. I can run my whole house from a leisure battery with 500w inverter as long as I leave fridge / freezer / washing machine / spin dryer / kettle / microwave out of the equation.
• 6th January 2014, 12:45 PM
CESIL
Quote:

Originally Posted by Marci
Yup - crucial thing with fridges is the startup load which generally lasts for about 3 seconds each time the compressor starts. I have an undercounter fridge with 1200w startup / 110w continuous... My 800w generator simply trips as soon as you plug the fridge in and won't entertain it. Essentially, your generator needs to be rated for greater than that startup pull. I can run my whole house from a leisure battery with 500w inverter as long as I leave fridge / freezer / washing machine / spin dryer / kettle / microwave out of the equation.

So you can run your whole house as long as none of the useful things are switched on? :p
• 6th January 2014, 06:47 PM
Marci
As long as the useful things are substituted for ones designed for the power situation... there's a difference.

i have two large 3 way cool boxes that fridge / freezer can be emptied into, which run off 12v or gas. Kettle is switched out for an old fashioned stove-top one. Microwave - requires the generator firing up... and we have a camping hand-turn washer thingy. Meanwhile, 2x LED TVs, 2x sky+ boxes, router & wifi APs and all household lighting (switched out to LED just before Christmas, reduced consumption of all lights in the house from 850w down to 70w) runs fine off the leisure battery.

Haven't sussed a decent solar/wind charging strategy for it yet, but am getting there... In meantime, if we have a power cut and batteries are fully charged I'm good for a day or two, and a calories gas bottle'll run the cool boxes for a week if not more. If batteries die, fire up the generator to recharge them.
• 7th January 2014, 10:08 AM
zag
• 7th January 2014, 11:04 AM
Greenbeast
Quote:

Originally Posted by Marci
As long as the useful things are substituted for ones designed for the power situation... there's a difference.

i have two large 3 way cool boxes that fridge / freezer can be emptied into, which run off 12v or gas. Kettle is switched out for an old fashioned stove-top one. Microwave - requires the generator firing up... and we have a camping hand-turn washer thingy. Meanwhile, 2x LED TVs, 2x sky+ boxes, router & wifi APs and all household lighting (switched out to LED just before Christmas, reduced consumption of all lights in the house from 850w down to 70w) runs fine off the leisure battery.

Haven't sussed a decent solar/wind charging strategy for it yet, but am getting there... In meantime, if we have a power cut and batteries are fully charged I'm good for a day or two, and a calories gas bottle'll run the cool boxes for a week if not more. If batteries die, fire up the generator to recharge them.

You should join up to the navitron forum, very useful bunch of guys (and gals) for renewable energy projects
• 7th January 2014, 11:56 PM
Sirbendy
I've got a whole bunch of SLA's here, and a small inverter. Used it last time the power went out - ran a CFL uplighter and the DAB radio for several hours off one 7.5ah one while we all ate tea and did some jigsaws before retiring to bed. It's a £5 80w inverter - tiny little thing. Just as a "why the hell not".

Based on that success, I am fully intending on getting a 20/30w solar panel, charge controller and battery pack setup that'll allow me to hopefully run lights/small appliances in possible powercuts again. Inverters are not needed for lighting - I've added 12v LED strip lighting in the kitchen - bright enough to work by. Equally, I have a lot of LEDS that I can use to make "backup" lights.

We have a gas fire, so no power needed there (unless I wish to run the back boiler, which is rated at..IIRC 15w, got to love old tech. Even without the circulator pump, it should run in gravity heating mode, giving the cylinder a boost). Cooker hob is also gas, and I have matches to light that if needed. Oven is electric, but it's manageable without.

Hallway has a "sensor" 2xAA powered 8 LED lamp in it that can be powered up in an emergency, will get another for the stairs. 40 seconds of light per "trigger". Very bright, more than enough.

Bathroom, I'd look at another one, OR possibly an LED "low level" lighting setup, using 1 watt power LEDs..been playing with one run from 4x NIMH AAs - heck of a lot of light there, good for a couple of days a go using standard white LEDS, probably less with a power LED. In the bathroom lighting is a "short use" thing, so..either would work.

Kids room is night-lit with LEDs anyway, on 12v at the mo. Am pondering installing a 7.5, maybe even just a 5ah SLA in the wardrobe, contained in a box with a mains hookup to keep it charged - run the thing all the time, then if the power drops out, they won't even notice.

Fridge/freezer, would be an issue. Unless I pick up a bigger inverter - maybe an old SmartUPS. Cheap, and easy.

I don't know, it's something I've wanted to really jump into for a while, heh. I already have a 12v/5w solar panel that's none too shabby at charging the SLAs, but I want bigger, and it's pretty cheap. I also have a salvaged 6v panel running as a NIMH charger - again, works well.

Petrol Generator..been looking at self-build jobs using scrap lawnmower engines and alternators..both of which I can acquire easily. Use to top up a 12v bank in an emergency.

Or maybe it's just pie in the sky. It keeps me busy though..heh. Should work!