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Off grid solar - need to move my house

Off grid solar - need to move my house

Off grid solar - need to move my house

(OP)
Having got my immersion heater wired into the solar, the sun stopped shining. The attached graph pretty much shows what happens each year. I've got about 3 square metres of panels, at say 10% efficient, so in winter I'll be expecting 5 MJ/m^2*.1*3/3.6 kWh, ie about 1/2 a kWh! At the moment I'm getting about double that, but no wonder the batteries are empty.

So I think a wind generator might be the next little project, that or a wood fired steam engine (save that one for retirement).

Just in case you think I am a total idiot, yes we do have a diesel generator that can charge the batteries at 20A (C20) while powering the house, I just hate the noise and the smell.


Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: Off grid solar - need to move my house

Can you get slightly better than 10% by angling the panels optimally? I'm assuming the data in the chart is per horizontal m^2.

RE: Off grid solar - need to move my house

You use metric and it's dark in July? You must be down-under.
Take a holiday on Flinders, and go see Mr. Oztules. He'll set you up.
I haven't encountered anyone who knows more about energy conversion systems (solar/hydro/wind/electromechanical) than him.
Since he writes prolifically, you can find a lot of good info on the internet, easily searchable.
Look especially for his WT maintenance and diagnosis writings, particularly for the AWP machines that he serviced. Some of the best though-out ideas about how to and how not to build a long-lasting reliable wind turbine, and fix it when it's broken. Once you've soaked that in, you can avoid buying the chinese crap that's being passed off and wind turbines these days.

STF

RE: Off grid solar - need to move my house

Greg:

Your graph seems to say that you get less sun exposure in the summer than the winter for Michigan. I find that very hard to believe. Maybe I am misreading it...

You sure this graph is not for somewhere in Australia, South Africa, or Argentina?

Mike McCann
MMC Engineering

RE: Off grid solar - need to move my house

Mike, Greg lives on the other side of the world, and the other side of the equator, from Michigan.

Mike Halloran
Pembroke Pines, FL, USA

RE: Off grid solar - need to move my house

Got it. Thanks... blush

Mike McCann
MMC Engineering

RE: Off grid solar - need to move my house

I've done both of these things:

DIY anemometer:

Stepper motor from a computer hard drive
+
Plastic egg cups
+
20 meters of telephone cord
+
tiny circuit board with a microcontroller counting pulses from the stepper
+
memory card/laptop/mobile phone interface to the uC
+
fasten to a pole
+
fasten pole to your automobile, to calibrate
+
Stick pole in back yard for several years.


Or...

Find a weather station close to your house and use the data from the government's weather service. Today.

STF

RE: Off grid solar - need to move my house

Or buy a $100 home weather station that has logging.

otherpower.com has some good info on DIY wind turbines, and homebrew anemometer. They have info on older projects all the way up to a large 20` blade diameter unit.

RE: Off grid solar - need to move my house

Kenat:

Some of us drink, some of us don't. I don't remember all the details all the time. I will remember this now though.

It did reinforce my intuition though. censored

Mike McCann
MMC Engineering

RE: Off grid solar - need to move my house

If we could just put turbines between the windbag politicians and the TV cameras the world energy problems would be solved.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.

RE: Off grid solar - need to move my house

I've tried those too.
You get what you pay for.

STF

RE: Off grid solar - need to move my house

There is some hope.
If you do get a home weather station, and confirm/calibrate the accuracy of the anemometer, will it log data to a computer? Maybe you can find one that will. Many won't. Some just tell you it's raining, after you come in the house and take your wet coat and boots off.

STF

RE: Off grid solar - need to move my house

Quote from dgallup "If we could just put turbines between the windbag politicians and the TV cameras the world energy problems would be solved."

No it wouldn't; all the wind turbine designs I've seed have to be feathered for self-protection during gale force winds.

RE: Off grid solar - need to move my house

May be there are too many trees and the leaves are blocking the sunshine.

RE: Off grid solar - need to move my house

(OP)
The trick with panels is to look at them when there is a good sun throwing sharp shadows. /Any/ shadow visible on the panels between say 10 am and 3 pm is a serious problem, time to get the chainsaw out. The other option is to use blocking diodes to prevent reverse driving of poorly performing strings of cells, but that is not an ideal solution.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

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