What size generator?

Katy43

I'm looking to buy a generator to keep my freezer going in the event of electricity cuts.

The freezer uses 318kwh per year with a power consumption of 0.87 kwh.

I've been advised by one company to buy a generator that has a starting wattage of 2,500 watts with 1,900 running watts.

Can anyone advise me if this size of generator is the correct size?

Many thanks

Section62

Katy43 said:

I'm looking to buy a generator to keep my freezer going in the event of electricity cuts.

The freezer uses 318kwh per year with a power consumption of 0.87 kwh.

I've been advised by one company to buy a generator that has a starting wattage of 2,500 watts with 1,900 running watts.

Can anyone advise me if this size of generator is the correct size?

Many thanks

You need one which can supply the maximum starting current of the freezer - this will depend on make and model of the freezer.

Once started most fridges and freezers draw a much lower current to keep the motor/compressor running. Hence the average current/power consumption is far lower.

If the generator isn't capable of producing the required output you risk causing damage to either or both the generator and freezer.  So you can view paying more for a larger output generator as an insurance against damage.

How often and how long are the power cuts you are concerned about?  Or is this a concern about what the future holds?

Katy43

Thank you very much for taking the time to reply.

It's a 6' freezer and I do rely on it, both in terms of economy and due to the rural location of home. Unfortunately, I've lost the manual and the manufacturer's helpline hasn't been able to advise much, although they did tell me that the connection rating would be 100 watts but that seems low to me?

GDB2222

Katy43 said:

Thank you very much for taking the time to reply.

It's a 6' freezer and I do rely on it, both in terms of economy and due to the rural location of home. Unfortunately, I've lost the manual and the manufacturer's helpline hasn't been able to advise much, although they did tell me that the connection rating would be 100 watts but that seems low to me?

100 watts seems a bit low, but 200-300w seems about right.  The motor on a freezer switches on and off throughout the day, and that's how you get an average usage of 0.87kwh over a 24 hour period. 

As S62 says, the starting power consumption when the freezer motor starts up can be far higher than the average power consumption. That could stall the generator, or even break it, unless it can handle that power demand for a second or two. Unfortunately, it only has to stall once for your freezer to become defrosted. The chances of damage to the freezer seem lower. 

I think you have no choice but to over-spec the generator, but I don't know how much by, and a 1900w generator doesn't sound completely insane.  

Katy43

Thank you GDB2222 for replying.

I've been pointed towards a Champion 92001i-DF.

Champion seems to have good write ups but can anyone recommend a make of generator?

Ebe_Scrooge

I can't help thinking that this may be a bit overkill.  I get where you're coming from - but how often do you have power cuts, and how long do they last for?  If you do have a power cut, then as long as you don't open the freezer door, the contents will be fine for many hours.

If it were me, I'd be weighing up the cost of a genny against the likelihood of experiencing a power cut of, say, longer than 12 hours in duration.  Of course, if this does happen fairly regularly in your location, it could be well worth it.  But is it really worth it if that eventuality only happens once every 10 years?  And if it does come to that, loss of food due to defrosting is covered on most household insurance policies anyway.

Section62

Katy43 said:

Unfortunately, I've lost the manual and the manufacturer's helpline hasn't been able to advise much, although they did tell me that the connection rating would be 100 watts but that seems low to me?

What is the make and model you/we can probably find the information online.  There should be a label or plate somewhere on the freezer giving these details if you don't already know them.

Section62

Ebe_Scrooge said:

I can't help thinking that this may be a bit overkill.  I get where you're coming from - but how often do you have power cuts, and how long do they last for?  If you do have a power cut, then as long as you don't open the freezer door, the contents will be fine for many hours.

If it were me, I'd be weighing up the cost of a genny against the likelihood of experiencing a power cut of, say, longer than 12 hours in duration.  Of course, if this does happen fairly regularly in your location, it could be well worth it.  But is it really worth it if that eventuality only happens once every 10 years?  And if it does come to that, loss of food due to defrosting is covered on most household insurance policies anyway.

Living in a rural area it is always worth considering a generator - not just for the freezer but also for charging mobile phones, laptops etc, or getting a router back online.  Some smaller kettles will also run off a reasonably sized generator (although not with other things running at the same time), which is another potential reason for buying a higher rated generator rather than the bare minimum.

We have an old 12v car battery we charge from the generator during longer power cuts, and can then use that via an inverter to power most of the downstairs lighting in the house. Makes life much easier compared to the old days of candles (and a camping stove).

fenwick458

I'd just buy a 3Kw generator. if it's going to be used for emergencies when the power goes off that way if you needed you could boil a kettle, plug in an electric heater (one at a time obviously)

GDB2222

fenwick458 said:

I'd just buy a 3Kw generator. if it's going to be used for emergencies when the power goes off that way if you needed you could boil a kettle, plug in an electric heater (one at a time obviously)

Plug in an electric heater? That’s a bit crazy thermodynamically. The generator is likely to have an efficiency of only about 30%, ie 70% of the energy in the fuel gets lost in heating up the generator and the outside air around it.  

Alanp

Have you tried pulling out your freezer and looking on the rating plate on the motor/compressor?, it usually gives you the info on that, ( wattages, amperage),