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wind friend

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Joined: 01/05/2007
Location: Australia
Posts: 39

Posted: 11:50pm 13 Mar 2011

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i've got 85 wats of solar on the roof charging 180 Ah of batteries and with a slightly too small pure sine wave inverter it will run the telly, set top box, dvd player and a couple of lights.

the grand plan is to get a bigger inverter and be able to plug any one load into it. fridge or kettle or etc.

at the moment the telly and sundries wants roughly 10 Ah at 12V. lets call it 120W(includung inverter losses)so for every 8 hours i save about $0.20. but this cant be why we do it. it must be the satisfaction of running an appliance for 'free'.

any thoughts?

VK4AYQ
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Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 12:11am 14 Mar 2011

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Hi wind friend

It is for the satisfaction of being able to tell the system to go to hell and dam the cost. Nothing in this life is free.

We are ripped of by the system all the time and its nice to know we can do it for ourself if we want. People spend more on smoking to kill themselves or alcohol the kill brain cells, or even coffee and cake at the local starbucks or whatever, than we do to become independent to some degree. What is waste and what is personal satisfaction?

You can reach your goal but don't expect to save money on energy as at the present you cant make it for the price you can buy it, but in the future who knows, be prepared and don't expect to much, remember a candle on a dark stormy is a comfort, but not a replacement to the 4 x 50 watt down lights and electric heater before the power went off.

All the best

Bob

Foolin Around

shawn

Senior Member

Joined: 30/03/2010
Location: New Zealand
Posts: 210

Posted: 08:10am 14 Mar 2011

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There are other reasons also, when I bought my new property (i now live here) i was told to bring power lines in and a transformar i was looking around 25 k and i would not own these i just had the right to use them and had the privilage of monthly power bills from then on.
Now everything i spend is mine but yes there are still costs.
OFF GRID RULES!!!!

VK4AYQ
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Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 09:38am 14 Mar 2011

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Hear Hear

Foolin Around

powerednut

Senior Member

Joined: 09/12/2009
Location: Australia
Posts: 221

Posted: 10:58pm 14 Mar 2011

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The on-grid costs add up pretty quickly. The connection fee, usage charges etc. And with energy prices set to increase by 50% over the next few years going off grid makes a lot of sense.

One of my coworkers managed a quarterly bill of $1300 for electricity last year. Other coworkers reported bills of $800-$1000 for the same winter period. It doesn't take long before not having to pay that makes one hell of a difference to your hip pocket.

Plus having lights and power when everybody else is blacked out is nice.

VK4AYQ
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Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 11:32pm 14 Mar 2011

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Hi Powerednut

Just before I went back to solar 2 years ago my bill had crept up to $2500 a year, so that made it mandatory.
The major contributer to the cost was hot water system,going solar there was a big help, but one issue has come to light is the split system pump and controller are using 120 watts and the way it is configured it runs 12 to 14 hours a day, still absorbing around 1.5 KW a day, I should have gone for a roof top unit.

I do have three phase power on for the workshop mainly but that gives me the opportunity to make a usable grid feed system.

And as you say having everything working when everyone is running around with candles is a good feeling.

All the best

Bob

Foolin Around

mid north Matt

Regular Member

Joined: 06/01/2011
Location: Australia
Posts: 58

Posted: 01:23am 15 Mar 2011

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hi Bob
do a seach for a solar power aircooler and theres links to a 12v car water pump/maximiser and its solar powered by a 5w panel,when the sun shines it pumps the heated water back to the ground mounted tank and save that 1.5Kw

Pt Wakefield Matt

VK4AYQ
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Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 04:39am 15 Mar 2011

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Hi Matt

Thanks for the suggestion, I will give something like that a try as soon as the warranty period is up.

I have a couple of old panels that are a bit sick, damm things only lasted 25 years

They are only giving 35 watts now instead of 80 a small pump and a 12 volt battery would do the trick I think.

So much to do so little time. I got more done before I retired, but I keep telling myself I am having fun.

All the best

Bob

Foolin Around

mid north Matt

Regular Member

Joined: 06/01/2011
Location: Australia
Posts: 58

Posted: 11:51am 15 Mar 2011

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hi Bob
it doesnt need a battery,its a minimiser/maximiser that drives a 12v craig davies car water pump that will run on a 5watt panel.the panel charges up big caps to a set voltage than dumps in on to the pump untill the pump runs sinse it take alot to get started but little current once going,abit like induction motors and you wouldnt want it pumping without sun to heat the water in the panels

Pt Wakefield Matt

VK4AYQ
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Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 01:12pm 15 Mar 2011

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Hi Matt

Thanks for that I will see if I can find one on ebay. I have got a 10 watt panel but I think it's 24 volt.

All the best

Bob

Foolin Around

norcold

Guru

Joined: 06/02/2011
Location: Australia
Posts: 670

Posted: 06:06pm 15 Mar 2011

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12 or 24 volt diaphargm water pumps can be got on Ebay(chinese)for $60 to $100. They work a treat, seem to last and can be run without batteries through a maximiser such as Shurflows. They come in many flow rates and have a pressure cut out switch installed. For cooling wrap some 1/2 inch soft copper tube(carefully so as not to kink) around the metal motor body, run the discharge water through this and they`ll run continuously. Float pump on your dam and that keeps the suction short. I see on Ebay there is a double ended one available, but from memory it draws 18 odd amps, but pumps 38l/min(no head)They will handle a head but flow rate drops off.

We come from the land downunder.
Vic

KarlJ

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Joined: 19/05/2008
Location: Australia
Posts: 1178

Posted: 10:06am 24 Mar 2011

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WTF? BOb it shouldnt be using anything like 120W
is it the type with a three position switch?
run it mid range and save 1/3 then try the 1st setting and
save 2/3. The Conergy one uses less than 20W.

Karl

Luck favours the well prepared

VK4AYQ
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Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 12:25pm 24 Mar 2011

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Hi Karl

It is a Conergy unit I have, and on the in line power tester it draws a total of 120 watts for the pump and controller, I checked the tester with a 100 watt globe and it is reasonably accurate for a Chinese junk thing.
So now I suspect a problem in the controller as well.

All the best

Bob

Foolin Around

KarlJ

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Joined: 19/05/2008
Location: Australia
Posts: 1178

Posted: 09:23am 27 Mar 2011

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Give Jarbar an email / pm, I think he has one of the conergy ones sitting around.

I know how he loves tinkering, perhaps he can do a few measurements with his.

I'm guessing load and no load would be similar as closed loop perhaps a few watts for resistance in thel pipe and friction.

if his comes up different, put in a warranty claim. all the literature I've read for them suggests they should use 2/3 of SFA.

Karl

Luck favours the well prepared

VK4AYQ
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Joined: 02/12/2009
Location: Australia
Posts: 2539

Posted: 02:16pm 27 Mar 2011

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Hi Karl

I have put in a claim through the installer and that is pending as it is now running all the time and not shutting of at night, I have to unplug it and plug it in in the morning.

All the best

Bob

Foolin Around

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