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Posted: Tue May 13, 2008 11:50 am
by Martin
well.........at around £600 for a fridge, and a need of probably £5k worth of solar equipment to drive it, you pays yer money, and makes yer choice........
These are made by Texans, for Texans, where "small" is obscenely huge - they're designed for a Texan climate, attitudes, and probably appetites too!
Yes, running a fridge/freezer is
possible from pvs, but to my mind borderline barking bats!

Posted: Tue May 13, 2008 1:45 pm
by tim&fatima
Thanx guys, interesting thread. I told the wife I was thinking about getting rid of the fridge and she said..F^@& ?:@~? <>| +_*& ^%$£.
So I can't see us getting rid just yet. If we grow enough produce we are looking to freeze some for the winter, so I may get a small chest freezer, and do away with the fridge/freezer.
(but lets keep that between us eh)
Posted: Tue May 13, 2008 2:12 pm
by MKG
Hmmm ... orgasms one day, fridges the next. Very demanding wife you have there (she told me to say that).
Posted: Tue May 13, 2008 2:31 pm
by Martin
for a moment I was getting troubling visuals.........
chest freezer - hmmm, chapel hat pegs............
But then I get similar problems with "remanded in custardy" (visions of criminals bobbing around in a vast vat of custard), and "gorilla warfare" - lots of hairy hominids lobbing grenades............

Posted: Tue May 13, 2008 2:31 pm
by tim&fatima
MKG wrote:Hmmm ... orgasms one day, fridges the next. Very demanding wife you have there (she told me to say that).
Tell me about it!
Posted: Tue May 13, 2008 4:34 pm
by Clara
The guy who previously owned my house had a much smaller and less efficient PV setup, but he converted a small upright chest freezer to a fridge, simply by putting a box that ran a changeable thermostat (a wire!) and fedback to a switch on the mains cable. He ran it in the summer when there was the power to use it and switched it off overnight. We haven´t used it because we haven´t found the need. I would find a freezer far more useful due to being able to preserve stuff - Martin do you have any thoughts about whether a small chest freezer (about a foot wide) could be run off a 720w system (system is German built)? Given that we will have several months of interrupted sunshine? I know that it a how long is a piece of string question, but be glad to hear your thoughts!
Tim, the following link from the Guardian might help clarify matters with your OH about how much you really need a fridge
http://lifeandhealth.guardian.co.uk/con ... 25,00.html
Posted: Tue May 13, 2008 4:46 pm
by Martin
I think the short answer is probably "yes, during the summer", but would question whether it would be worthwhile probably using most of your system's storage capacity to do it! You'd probably also have problems arising because once the freezer contents have risen above a certain temperature you should dump the lot - (as could easily happen - you need a constant supply for a freezer). If you really want a freezer, I'd go small caravan calor gas job in an outhouse, and keep the existing system for things that you really must use electricity for!

Posted: Tue May 13, 2008 4:55 pm
by Clara
Problem with gas is that we have to carry it a couple of miles here

, I was thinking that when we next have a baby goat to freeze I might exchange some of it for storage of the whole thing in a on-gridder fridge....though that tugs a little on my ethics

Posted: Wed May 14, 2008 9:40 pm
by Boiled frog
I don't have a cellar, pantry, stone shed or any other suitable storage location to replace a fridge, but instead of a pot-in-a-pot I wondered about making a small earth covered storage area, about the size of a dustbin laying on its side, with a cooler box inside. My thinking was that caves are always cold and with sufficient soil I could construct a well insulated mini-cave

Does this sound feasible?

With 3 kids I need a reasonable storage area and I'm not convinced the pot-in-a-pot would work for me, or am I mistaken?
Paul
Posted: Thu May 15, 2008 8:33 am
by ina
What I have done, in times of the year when it's just a little too warm to do without a fridge, used my cool box and swapped the cooler thingies in it (grr, can't think of the right word!

) every day with fresh ones from the freezer. Only - this always leaves me wondering whether I use more energy opening and shutting the freezer daily and re-freezing the units than I would use in the fridge?!
Posted: Thu Jun 05, 2008 2:08 pm
by DominicJ
Warning, I know nothing
Forgive me if I'm wrong, but, a fridge keeps things cold, its job is hardest during the day, when its sunny, which is also when solar panels work best.
So, provided you were to keep your fridge full, IE hide beer in all the empty space, it would be fine?
Overnight it should be ok just with ambient temperatures, maybe, or perhaps a battery.
Theres a 9.2 cu.ft fridge that uses 167kwh a year on ASDA, so thats 500wh a day.
Could you not power it completely with a couple of big panels a big battery and a cheapy inverter? For maybe £600?
Posted: Thu Jun 05, 2008 3:44 pm
by Clara
DominicJ wrote:Warning, I know nothing
Forgive me if I'm wrong, but, a fridge keeps things cold, its job is hardest during the day, when its sunny, which is also when solar panels work best.
So, provided you were to keep your fridge full, IE hide beer in all the empty space, it would be fine?
Overnight it should be ok just with ambient temperatures, maybe, or perhaps a battery.
Theres a 9.2 cu.ft fridge that uses 167kwh a year on ASDA, so thats 500wh a day.
Could you not power it completely with a couple of big panels a big battery and a cheapy inverter? For maybe £600?
Is there a freezer equivalent? I really don´t need a fridge, but a freezer would be desirable, for use during the summer (when there is constant solar power available) to free up some of that time (like all my time

) spent making everything from scratch.
Posted: Fri Jun 06, 2008 8:19 am
by DominicJ
175 litres using 254kwh a year for an upright freezer.
These are just cheapies on ASDA.com
Presumably if you put a fridge/freezer in a cold room it would require even less solar?
I'll go system shopping in a moment and show you what I was thinking
Posted: Fri Jun 06, 2008 8:50 am
by DominicJ
The fridge and freezer I pointed out consume 421 kwh a year
A 300w sinewave inverter costs about £120
2 55w solar panels is about £400
10amp charge controller for £100
This is where my maths gets iffy
http://www.wydels.co.uk/product.asp?typ ... rodID=4611
I think that battery would run both for a day and discharge 50%, which should get you 1000 recharge cycles acording to the website.
Oh, and costs £170
So, for £800, you should be able to power your fridge and freezer off renewables.
I may be wrong, its a pretty common occurance, but if I'm right, that seems like a pretty cheap and useful way of getting afoot in the door of renewable energy.
So, would anyone wiser than me care to check?
Posted: Fri Jun 06, 2008 9:42 am
by contadino
Fridges and freezers are complicated beasts. If you put them in a cold place, they'll heat it up, because they generate a fair bit of heat - even efficient ones. What you need is something to vent that heat outdoors.
Also, I've read that the pumps on them have quite big surge demand, so a 300w inverter might not be big enough. When the pump cuts in, it can take 3 times the current.
And there's also the issue that you need it to work hardest when the ambient temperature is at it's highest.
Having said that, I don't think it's as big a deal as others believe it to be. Last time I looked off grid freezers in depth, I concluded that it was best (for me) to build a 12vdc freezer into a suitable spot in my house. You basically build a mega-insulated box, attach a 12vdc freezer motor/controller, and put a vent in. I think the company I was considering buying the gubbins from was call Vessfrost or something similar. Unfortunately it was on my old 'pooter which fizzled out.