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hedgewizard wrote:By the way Christine, the thing about full freezers being more efficient is a myth - check out this link to see why!

hmm i get their point.. but in the same way as the website invites you to

detect that it must be dubious advice because of what people suggest for filling the space

i am now dubious as I have always been told to fill empty space with water filled containers.

They dont seem to back up their claim its a myth with statistics either.....
I do agree with their point that the worst is keeping the door open for long periods.

this is the way I see it. if you had two identical freezers one empty and one filled with boxes of ice, both were down to say -18 and then you had a power cut.. I am convinced that after 8 hours the freezer full of ice would be colder inside than then empty freezer - therefore it is better to keep your freezer full.

As far as I've always believed the "fullness" of the freezer only saves energy by preventing cold air to escape when the door gets opened. So if you don't open the freezer often, it won't make a blind bit of difference whether the freezer is full or not... And the drawers themselves should prevent most of the air escaping.

Another thing I thought of when mulling over why somebody should think they couldn't turn the freezer off because it might not be good for it - well, a freezer that didn't survive multiple turn-offs and -ons wouldn't last long in some parts of Scotland where power cuts are quite a normal occurrence! Other countries are worse in that respect, I believe. When I was in France (admittedly, a fair few years back), we lost power most afternoons - and were dependent on freezers for cheese storage etc.

Aren't there some freezers that save power by switching themselves off at certain times of the day? Admittedly the motors have been designed to live like that but it seems to imply that you can switch them off and on.

Cheers
Zoe

I'd be interested in a canner; but even with safety canning process and stuff I'd still be freaked out about bottulism.

Red, we're asking two different questions here. As regards keeping things frozen in a power outage, the freezer wants to contain lots of mass with a high thermal capacity - so water-filled containers are brilliant. As regards energy consumption, it makes very little difference what's in the freezer compared to energy lost opening it and cooling down non-frozen additions. Must go and look in Seymours now, although I always find that book big on generalities and very light on detail!

Dried apples - we eat them, mainly! They're so delish that there's always a fight over them, but they'd also be a good addition to soups needing a little sweetness, or porridge if I fancy a change to my usual add-ins. Basically though, it's a second-line storage option. Perfect specimens of cookers and eaters get wrapped and trayed, but imperfect cookers get frozen (or processed and frozen), and imperfect eaters get dried.

Nutrients - hmm, hard to find but the US Department of Agriculture Research Services Division said in a study of preserving methods for Carrots, Peas, Potatoes and Apricots that "almost always the nutritional value in the food isn't greatly reduced by the drying process." Which is nice, if vague. Canning, by the way, came out much worse than both freezing and drying.

Baked beans using fresh sounds yummmmmy - but it'd be happening at the height of Keats weather so I think it might tip me over the edge!

hedgewizard wrote: Baked beans using fresh sounds yummmmmy - but it'd be happening at the height of Keats weather so I think it might tip me over the edge!

nice use of a link to your blog there
personally I really enjoy the business of harvesting and processing your produce. - albeit hard work all at once. but making baked beans is a doddle.. sling it together.. put in oven.. have for tea.


regarding the full freezer vs empty freezer question - you re right opening the door is the worst way of wasting energy. but assuming you do this just as much if your freezer is full or empty, then i still believe a freezer with free space filled with water containers will use less electricity - - let me try this another way - if you had two freezers.. and freezers are insulated as you know, and one was filled with blocks of ice, and the other was empty, then it would take less electricity to lower the inside temperature by one degree in the filled one, *because* the iceblocks would be keeping the internal temperature down .

Now I do not have any scientific data to back up my theory.. I would be interested to know if I am right or not (and if not, then I can change my ways and save more electricity!) but - the link you sent explaining it was all a myth also does not have any data either.. just states its best not to open the door alot.. and we know that...

I'm glad you enjoy your dried apple slices.. we dont have a lot of eaters here, more bramleys.. and the eaters we did have were eaten or went into my cider and wine making exploits. but I still like the concept and as soon as I have worked at an energy free (or at least secondary use of energy, such as above the oven etc) way, I'll be onto it.
Meanwhile we have decided to buy a second freezer.. prolly the one I pointed at, to deal with other items such as cauliflower and lambs next year (hopefully) which dont tent to dry so well....

red wrote:

hedgewizard wrote: Baked beans using fresh sounds yummmmmy - but it'd be happening at the height of Keats weather so I think it might tip me over the edge!

nice use of a link to your blog there

Yes, wasn't it?

It's all about thermal capacity. Water holds a lot of thermal energy, air holds practically nothing - that's why we don't take "hot air bottles" to bed at night.

So yes, the water-filled freezer would take more energy input to raise the temp by one degree, no question. However, when the door is open it ships ambient energy in at the same rate - so the energy cost is the same. I can't remember the maths here but even if the temp only goes down by a hundredth as much in the water-filled unit as the air-filled one, the freezer still has to ship out the same amount of gained heat so the costs should be similar. God, now I'm confused.

Trying to cut the air/water thing out of it, it doesn't matter what the actual temperature difference is - it's the amount of heat shipped in while the door is open that matters, and that's practically the same between the two. However, your water-filled freezer will withstand power cuts better - so go for it!

hedgewizard wrote: Bosch are quite coy about what their "running cost" actually means, since it depends on how much throughput the unit gets, ambient temperature and a bunch of other stuff; I think their figure is a projection based on a closed unit maintaining itself against a steady ambient temperature. Now if you'll pardon me, I have cucumbers to pickle...

thought I would update that we did go ahead and buy the bosch upright freezer and it has worked out well so far - we have been monitoring the electricity usage as we have one of those plug in gadgets that tell you how much an appliance is using (very handy too as we found out the under counter fridge we inherited with the house accounted for a HUGE chunk of our lecky bill... we got rid after that...)
We have found that freezer uses less electricity than their estimates, although this has been through Autumn and into winter.. it might be different in summer.


scarily we managed to fill it almost immediatly, and I still have apples to process!