Running Costs for Freezers

Chest Freezer

With growing our own food, we need to store it. We enjoy seasonal food but it's nice to have a selection available all year round and a freezer is ideal for this. Like most people we have busy lives and the freezer helps us there. It takes no longer to make 2 shepherd's pies or lasagnes than one, enough soup for 6 meals as one, so we bulk cook and freeze.

Then when we are busy, we can pop into the freezer and defrost a 'ready meal' except that this is a genuine home cooked meal. We're also bargain hunters; when the shop reduces something because it is at the end of its shelf life, we grab it. Our best bargain was a chateaubriand reduced from £27.99 to £4.99. By freezing we can hold the bargain until we're ready to eat it.

Now this has meant that we've acquired 4 freezers. Second hand bargains, of course. A small chest freezer, a small upright freezer, a tall upright freezer and a fridge freezer. Perhaps a bit much for two of us and four cats, but that's how things have worked out.

With the increasing cost of electricity, we decided to see how much they actually cost to run and to measure the effectiveness of a device called a Savaplug that is claimed to reduce running costs for fridges and freezers. The results were interesting and in some cases, the costs were chilling. Sorry about that pun!

We bought a power metering device that tells us how many hours it has been running since the last reset and how many KWh have been consumed. Since we pay just over 11p per KWh, we can calculate running costs with a bit of maths. A KWh is a unit of electricity – one kilowatt run for one hour.

We also checked the freezers performed as well with and without the Savaplug using a maximum / minimum digital thermometer with a sensor on a lead. This also enabled us to make sure the temperature wasn't going up and down as the device kicked in and out and the temperature was the same with and without the device.

Unfortunately Savaplug seems to be sold out everywhere at the moment but you might find some on ebay.

Test Methodology

1. Each freezer was run for a minimum period of 24 hours without the Savaplug and then with the device connected. Temperature was measured continuously and no difference was found.
2. At the end of each test cycle the KWh consumption and running time was noted. By dividing by the number of hours on test, power used per hour was calculated.
3. By multiplying this figure by 24 hours in the day and 365 days in the year (8,760), annual running costs were calculated on the basis of a cost per KWh of 11.7p

Results

Tall Old Upright Freezer Running Cost

First up was our old tall upright. It's seen better days but it still holds temperature down and it's convenient. I'd estimate its capacity around 7 cubic feet.

Without the Savaplug it would cost us about £111 pounds a year to run, consuming 950 KWh of electricity. Not unexpected, it's before the days of efficiency ratings. With the Savaplug running the figures dropped dramatically. It was just using 556 KWh a year, costing us £65 pounds. So we are saving £46.00 a year using a gadget that only costs around £25.00. Now that is a good return on our investment.

Electrolux Premier Eco Freezer Running Costs

The next freezer we checked the running costs on was a fairly new, about 14 months old, Electrolux Premier Eco freezer. I think the capacity is about 4 cubic feet.

This is an A+ rated appliance so we expected it to be very economical to run. It is, however, a 'frost free' freezer and I've heard these can be expensive to run. It's an upright freezer again and has drawers with solid fronts, which should help to keep in the cold when the door is opened.

We discovered the normal running costs are approximately £34 a year, using some 290 KWh of electricity each year. Adding the Savaplug to the equation, the running costs fell to £24 a year using 207 KWh of electricity. A slower return for our cash investment in energy use reduction but still 40% That's far higher than any inflation proofed savings account.

Chest Freezer Running Costs

Next to the small upright freezer, we have a Whirlpool chest freezer. It takes up the same room as the Electrolux and is nominally around the same 4 cubic feet capacity, but we find you can get a lot more into it due to less air gaps than with drawers. I think this is actually 'C' rated although chest freezers seem cheap to run anyway and are certainly cheap to buy, even new.

The running costs are £33 a year using 283 KWh each year. Because we only have 3 Savaplugs this was not tested with a Savaplug but I would bet it would reduce the freezer's running costs.

Frost Free Fridge Freezer Running Costs

Finally we tested the fridge freezer in the kitchen. This we bought from new about 5 years ago and, if I'm truthful, we paid more attention to the size and internal fittings than the energy efficiency at the time.

One problem we do have with this appliance that we didn't realise until we'd had it for a while is that there is only one temperature control. We need the freezer to run at between minus 18 degrees and minus 20 degrees. To achieve this the fridge section has to run at around 2 to 3 degrees when 4 to 5 degrees would be ideal. So we pay extra to run the freezer in over-cooling the fridge.

Once again we compared costs with the Savaplug, some £60.00 each year and without it costs rise to £114.00 each year. That's a huge difference.

Conclusion

Freezers are a great way to store food. Properly blanched, we have kept vegetables for two years without noticeable deterioration.However, you do need to keep an eye on the running costs.

Buying a fairly new second hand freezer makes good sense, our dumps are full of perfectly working fridges and freezers so getting an extra 5 or even 10 years life from an unwanted appliance is good. Even if the second hand freezers are not as efficient as a new freezer it makes ecological and economic sense to go for second hand.

If you can obtain a Savaplug or equivalent, they're well worth buying. The return on your investment is far higher than any bank. Not all freezers, particularly expensive ones with electronic displays, can be run with a Savaplug. They do provide a list of unsuitable appliances which you can find on Nigel's Eco Store.

When buying a new fridge or freezer, go for the best energy rating models only.

When buying a fridge freezer, look for one where you can control the temperature in the freezer and fridge separately.

Avoid fancy frost-free freezers. They generally work by blowing air through the cabinet that removes moisture-laden air reducing the amount of frost build up. The advantage of not having to spend a couple of hours defrosting every six months or so is far outweighed by the additional running costs and risk of more mechanical parts failing.

Chest freezers, even if nominally lower rated for energy saving, seem more intrinsically efficient. Because when you open the lid the cold remains in the cabinet, they seem to use less energy in re-cooling. You can also get more into them for a given size.

If you find a large chest freezer and you've space for it, then go for it. You can save a small fortune by storing your own produce and picking up bargains at the end of their sell by date.

Freezer & Energy Saving Resources

• Big Green Smile - an online shop specialising in ecologically sound products including meters and standby busters etc
• Nigel's Eco Store - another online shop specialising in ecologically sound products.