|
| Author |
Message |
Ontario lakeside
Member
|
# Posted: 25 Jul 2016 11:36pm
Reply
Hello all.
I have a 12 volt system in place now that powers my water pump and lighting that is working well but is not suitable for upgrading. I would like to add a separate system to handle refrigeration. We have excellent solar exposure. We would need enough power for a 4-6 CF standard mini fridge.
what am i looking at as far as panels and batteries required?
Thanks very much.
|
|
sloweather
Member
|
# Posted: 26 Jul 2016 01:26am
Reply
As I mentioned in in another thread, I think you would be better served by an absorption cycle propane RV/camper fridge.
Else, we need to know your latitude for sun exposure, and the power draw of your proposed fridge.
Interpolating from http://www.wholesalesolar.com/solar-information/how-to-save-energy/power-table, a 6 ft^3 fridge might use 500 watt hours per day.
At my latitude of 35 degrees N in the US, you would need a base of 2000 watts of solar panels (max 5 hours daily charging in the winter), and a 42 AH 12 volt battery. Double the battery size to at least 80 AH to maximize battery life.
Now to the rules of thumb... Triple the solar array to cover consecutive cloudy days to at least 6000 watts. At least double the battery again to 160 AH for the same reason.
And then you need an inverter. Don't even think about using an RV fridge in DC or AC mode... That's all resistance heating to replace the propane flame. IMO, you would need a compressor unit.
All of that is just a rough guess without more detail
|
|
Steve_S
Member
|
# Posted: 26 Jul 2016 08:39am - Edited by: Steve_S
Reply
@Lakeside, check out the kits @ SolaCity in Kemptville http://www.solacity.com/product-category/kits/ Rob Becker's is great & answers all questions quickly.
or from here @ https://translate.google.ca/translate?sl=auto&tl=en&js=y&prev=_t&hl=en&ie=UTF-8&u=htt p%3A%2F%2Fwww.energie-abordable.com%2F&edit-text= Yves Julien (speaks English) is also a great resource with good info & very helpful too, he sells on EBay as well...
My solar kit came from SolaCity and my Inverter/Charger from Energie Abordable... The 2nd place (French site in Montreal) is mostly aimed at the boating & RV community which is more dialed into "Small Standalone" systems and cheaper it seems... Boater's & RV'ers having been at the independence stage a lot longer than anyone else....
Thing is, there is a lesson learned here in regards to not being able to expand your existing setup. When planning out your new system for the fridge, design it with components that would let you expand later if desired without another major reinvestment. Especially considering that pricing continues to drop and the tech is changing / evolving faster & faster all the time...
|
|
creeky
Member
|
# Posted: 26 Jul 2016 09:11am
Reply
an electric fridge is an excellent idea and far superior (imo) to gas.
If you are running your fridge seasonally (ie. spring summer fall) then you need 500w panels. And 500amp lead acid or 200ah lithium (at 12v nominal). Really you only need overnight carrying capacity. But a little extra won't hurt.
A charger and genny for emergency charging is also a good idea.
Notes:
1)
Double check the energy star rating. Some of the small fridges are under 300kw annual and others ... you might as well get a larger fridge. Location is also important. Most small fridges need air space around them. And the cooler the location the lower the energy cost. (needless to say).
By ex. My 10 cu ft is 311kw/annual. So if a 3/4 cu ft is 300 or 289 or similar. Why not just go 10 cu ft?
2)
Propane fridges are more expensive to buy. Have less room in them. And cost money every day in propane costs.
By ex. my 10 cu ft fridge has now been in service for going on 4 years. I have now saved aprox. $1600 in propane costs over my earlier propane model which was only 8 cu ft.
The electric fridge was also $1200 cheaper to buy. So you could say I have saved $2800 so far.
3)
I am offering solar consulting on off grid systems now. The fee is very reasonable. Assembly and testing are also available.
Contact me through a new website that I've started building. Here Use the comments feature for now.
|
|
Bret
Member
|
# Posted: 26 Jul 2016 11:42am
Reply
Hey Creeky:
Are you Kelvin?
|
|
shall
Member
|
# Posted: 26 Jul 2016 12:20pm
Reply
interesting video I saw recently on the subject
https://www.youtube.com/watch?v=YrHN6iTMtvM
|
|
Ontario lakeside
Member
|
# Posted: 26 Jul 2016 12:55pm
Reply
Thanks everyone. Im not interested in propane. My existing setup was around $200 so I'm happy to leave it place and add another. Im thinking a small chest freezer modified to work as a fridge is the way I will go. A 5 CF model I'm looking at uses 196KWH as a freezer, should be less as a fridge.
Im at 44 degrees north. I have unobstructed east south and west exposure. my existing system gets 8+ hours of sun this time of year. on a manually rotated mount.
|
|
shall
Member
|
# Posted: 26 Jul 2016 01:07pm
Reply
just as a somewhat coincidental aside, assuming that you are the same Ontario Lakeside as the youtube channel, I watched your video last night on the light fixture you made with an LED strip and broom handle. Neat stuff
|
|
|
shall
Member
|
# Posted: 26 Jul 2016 01:17pm
Reply
actually, I can't recall if you used the broom handle in the actual fixture or if that was just to make the star wars light saber. lol
|
|
Ontario lakeside
Member
|
# Posted: 26 Jul 2016 01:39pm
Reply
Hey Shall
I am that same Ontario Lakeside. Thanks for the comment. In the end I didn't use the broom, but the light is working great!
|
|
Ontario lakeside
Member
|
# Posted: 26 Jul 2016 01:39pm
Reply
What do you guys think of the video Shall posted above?
|
|
Atlincabin
Member
|
# Posted: 27 Jul 2016 11:19am
Reply
You can also purchase highly-efficient 12V refrigerators (Sunfrost is one brand) but they are probably more expensive than adding panels and batteries to your solar system! Smaller 12V compressor refrigerators (like 1-3 cubic ft) are available on the over-the-road trucker and RV websites. These are not as efficient as the Sunfrost type, but are much smaller and a bit less expensive. And being compressor units, they don't use the same amount of energy as the three-way RV refrigerators.
Greg
|
|
rockies
Member
|
# Posted: 28 Jul 2016 08:49pm
Reply
Since one thing guys love is competition, maybe we could start an "energy efficient appliance" contest.
For example, Creeky says his fridge runs at 311 kw/annual and Ontario lakeside says the chest freezer he's looking at runs at 196 kw/annual.
Why not mention Brands and models of fridges, freezers, washing machines, dryers, stoves and small appliances and see who comes out on top?
|
|
old243
Member
|
# Posted: 28 Jul 2016 09:12pm
Reply
Isaw a ad on ebay. Advertising solar panels and a lot of equipment for sale. Believe it is in Toronto, you might all be aware of it, but will mention anyway. Solarshoppingmall.com
www.sawtechnology.com 9055671804. old243
|
|
Ontario lakeside
Member
|
# Posted: 28 Jul 2016 10:29pm
Reply
Thanks for the tip
|
|
moneypitfeeder
Member
|
# Posted: 31 Jul 2016 03:19pm
Reply
Here's an article you all might find interesting, we were considering a chest freezer convert. but, we have gotten our propane fridge/freezer working again. (Mice had removed a ton of the insulation in the heat exchange box, replaced w/some spare roxul & a metal screen to keep them out, and she's good as new.) http://www.builditsolar.com/Projects/Conservation/chest_fridge.pdf If anyone does end up trying this w/ solar, I'd love to hear brand (model) power consumption etc. Our current propane model is likely from the 70's-80's, is fully propane, w/ no light or anything and the price to replace it is huge in comparison to a chest freezer.
|
|
creeky
Member
|
# Posted: 2 Aug 2016 09:38pm
Reply
saw a 3 cu ft fridge yesterday at home hardware. had the tiniest freezer I've ever seen.
anyway.
188 kw/yr.
to put that in perspective. that's 80 kw less than the previous lowest.
would mean a 100 watt panel and some lithium batteries would get you through a summer of fridge use.
propane. what's that?
|
|
Ontario lakeside
Member
|
# Posted: 2 Aug 2016 10:29pm
Reply
Thats amazing, I can't wait for the day I can take my city house off grid!
|
|
creeky
Member
|
# Posted: 3 Aug 2016 10:38am
Reply
It was pretty cool. esp when the "energy guide" had 266 kw/y as the low mark on the graph.
yup. off grid city house tech with batteries is available now. it will be wonderful watching the conversion to distributed power over the next decade.
fronius and SMA seem to be leading the way. btw. I have an inverter and lithium battery for sale. grin.
|
|
Atlincabin
Member
|
# Posted: 5 Aug 2016 10:03pm
Reply
My fridge is a 10.4 cubic foot Vissani. On the EPA website it is listed as consuming 35.6 watts/hour on average. I recently measured this with a Kill-A-Watt meter and over 4 days it was consuming about 28 (thats a 20% difference), so I'm pretty happy with it. For comparison, the SunFrost 12 cubic foot fridge is supposed to consume about 12 watts/hour. However, last I looked, the Vissani was about $350 and the SunFrost about $1800. For the difference, one can purchase a couple of solar panels that will easily cover the electrical demand, provided your batteries are up to it.
Greg
|
|
davestreck
Member
|
# Posted: 6 Aug 2016 07:38am
Reply
Is the efficiency of a normal AC fridge affected when run off a non-sine wave inverter?
|
|
Steve_S
Member
|
# Posted: 6 Aug 2016 08:29am
Reply
http://www.analyticsystems.com/blog/2013/inverters-modified-sine-wave-vs-pure-sine-wa ve
http://www.powerstream.com/inFAQ.htm
http://www.homepower.com/ac-output-wave-forms
In short, all Inverters use one form of Sine Wave to another. The best for Electronics, Sensitive devices and High Performance electrical motors, is Pure Sine, followed by Modified Sine. Square Sine should only be used with very tolerant equipment. Clean Pure Sine Wave actually saves power on electronics and motors and is less "wear & tear" on electro-mechanical devices (less pulses & cycling of power).
I have never heard of a "Non-Sine" wave Inverter...
|
|
bronco_ed
Member
|
# Posted: 13 Feb 2019 12:00pm
Reply
Quoting: rockies Why not mention Brands and models of fridges, freezers, washing machines, dryers, stoves and small appliances and see who comes out on top?
interested in hearing what electric coffee makers are used...
|
|
|
