Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

donate to eham
   Home   Help Search  
Pages: Prev 1 [2]   Go Down
  Print  
Author Topic: Off-Grid Operation in My Shack  (Read 1244 times)
VK2NZA
Member

Posts: 275




Ignore
« Reply #15 on: July 11, 2019, 05:36:19 AM »

KC6RWI, there are losses in the use of an inverter, the losses vary with the quality and design however the best rarely exceed 90 -93% efficiency, my Outback controllers and their ilk run small computer fans to cool components intermittently when panels are pumping higher amperages into the battery banks.
MMPT regulators are quite efficient especially if you series panels bringing in higher voltages, particularly for longer wire runs from solar arrays, smaller wire size etc, the regulator will auto correct to battery bank voltage using some quite sophisticated electrical algorythyms to best charge the banks.

Mark K5LXP, here in Australia AGM batteries have come down in price considerably due to the high take up of solar powered household, (we are a country blessed with sun)  and are quite competitive with quality Lead acid deep cycles such as Trojan etc, around a 10% premium in my case.
I'm also now using AGM batteries in my diesel pickup and diesel Landcruiser as I find a much better lifespan (about 6 years + Vs 3 approx) than conventional vehicle starter batteries and their higher amperage delivery spins a high comp diesel starter better than my last L/Acids. A 130 A/H AGM for the pickup costs me $240.00 AUS about aprox $150 -160.00 US.

If initial price is less of a consideration the new style alkaline Nickel Iron cells are a good choice with a 20 year guarantee here and a claimed 30 year life span, when they die, just replace the electrolyte and they're good to go for another round! Claimed 90% cycle without lifespan loss.

Tesla powerwalls are commonly installed for grid interactive systems here in Aus and a number of newer local design however I personally find them not so cost effective as yet here.

AGM's I've found are far less resistant to a charge and they will charge faster and can be cycled more deeply(50% claimed ) than Lead acid around 20% for safety!
AGM's are also capable of delivering a larger amperage on demand than most Lead acids when starting large loads.
AGM's also have a much reduced static discharge than lead acid when standing unused for long periods.
I ran large banks of Lead acid for many years and generally had good results with quality brands but have switched to AGM finding a number of benefits.
But again buy a quality brand as there is some variation in quality, I am using Chinese manufactured cells from a reliable local supplier and find they are very good value.
 Any way we haven't missed the quarterly power bill and much of the time we don'y use all the power our solar arrays generate with the regulators floating by 1100 -1200 daily.

Logged
KC6RWI
Member

Posts: 170




Ignore
« Reply #16 on: July 17, 2019, 08:17:19 PM »

Thanks, I am still working on it, in the city here you can't just put up solar panels on the roof without permits, and I am not sure that you can do that as a home owner. But what the yl wanted was a back up for the full sized fridge. I am exploring battery possibilities. AS a back up I could exercise the system and save a little power as well.
Logged
VK2NZA
Member

Posts: 275




Ignore
« Reply #17 on: July 19, 2019, 08:05:51 PM »

Hi KC6RWI,
   I didn't realise you would need a permit to place solar panels on rooftop , here in Australia it is encouraged by local, state and federal govt.
We can apply for and receive subsidies to install rooftop solar, it varies from state to state, but the subsidy can amount to several thousand dollars, low income earners and aged pensioners will soon be entitled to a free installation of grid interactive solar in certain areas to assist with power bills.
We are blessed with very high sun levels and days here and it is very common to see solar arrays on dwellings here.
Logged
K5LXP
Member

Posts: 6092


WWW

Ignore
« Reply #18 on: July 19, 2019, 08:45:00 PM »

If all you're looking for is a stopgap to save a $100 worth of food then buy a small generator and be done with it.  Run it a couple hours twice a day and that will keep the fridge happy, meanwhile you'll have a power source that can be used wherever you need one and won't be reliant on a sunny day.  Solar can be fun and interesting but you're proposing to go down a long and winding road with it not to mention tying up a bunch of money just to run a fridge once in a blue moon.  With a genset you plug in and are done.

Mark K5LXP
Albuquerque, NM
« Last Edit: July 19, 2019, 08:49:20 PM by K5LXP » Logged
K6AER
Member

Posts: 5689




Ignore
« Reply #19 on: July 28, 2019, 06:01:47 PM »

Harbor Freight, $399 - 4 KW.
Logged
K6BRN
Member

Posts: 1267




Ignore
« Reply #20 on: July 28, 2019, 08:12:25 PM »

Propane refrigerator:

https://uniqueoffgrid.com/category/propane-fridges/

Or... the best generaor going for this use - the Honda EU2200i.  Very quiet.  Way more efficient on gass than the Harbor Freight stuff. and will run reliably for MANY hours without failure - plus easy to carry in/out. Read the reviews.  I've run Honda EU6500's, EU2200's and EU1000's.  Never let me down.  Just don't let E85 gasohol sit in (any generator) for a year.  It turns to sludge.  As you shut down, make the last few oz. engineered fuel (plain gasoline) and run it until the carb empties.  The EU2200is is designed with this in mind - easy to do.

Sips gas, can run MANY hours.  Great for solar backup/battery bank charging.

An interesting and very common way to go in off-the grid New England homes and cabins is propane for cooking (propane stove), heating (furnace or just an iron propane stove - or a WOOD stove) and refridgerator/freezer.  Then solar with a small backup generator for LED lights, phone charging, etc.  Generally its a bank of 20 lb propane bottles if its a carry-in only location (like an island) or delivery of 100-200 lb bottles if you have road access.  Gas is easy.  Just bring a 5-gallon can.  With the Honda, backed up by solar, it'll last quite a while.

Been there, done that.

Have fun!

Brian - K6BRN
Logged
WA8NVW
Member

Posts: 18




Ignore
« Reply #21 on: August 12, 2019, 04:01:35 PM »

Don't buy lead at all, period.  The very last thing you want is to be stuck with the end-of-life disposal, transportation, and burial costs of all that lead a few years down the road.  Especially if you reside in California or other ecology-minded states.
Consider going with Li-Po technology instead.  It offers much higher power density and much higher charge cycle count.  This past weekend I saw a field operating demo with an IC703 at 10 W PEP out, using just a 9AH (108W) Li-Po pack as the power source.  The rig runs for over 8 hours without needing a charge. 
Logged
Pages: Prev 1 [2]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!