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[aprssig] Shack backup power

KBØNLY kb0nly at mchsi.com
Sun Sep 11 16:40:52 UTC 2011

This just goes to show no backup setup is perfect.  Grid tie is the most 
economical of solar systems, no battery cost and immediate return on the 
investment with net metering.  However its not intended as a backup source 
and should not be sold or treated as such.  So to say it fell flat on its 
face is dumb, that’s like saying my new car I bought can't tow my 20ft boat 
and I should have bought a truck.  You have to buy the right thing for the 
support you need in the first place.  The problem is companies selling and 
installing these systems do not fully explain them and are only looking at 
the profit line.

If I had the capital to spend on such an install I would put in grid tie 
solar, as 99% of the time it would be perfect for my needs, a small 
supplement to offset my power usage, that’s all I need.  When I get an 
outage I crank up the generator.  Nobody can tell me different, I went 
through a tornado here July 1st, three days without commercial power, I was 
the only one on my side of town with any source of backup, solar, generator, 
or otherwise.  Solar would have done me NO good as a backup, even with a 
large battery bank it would have been played out before commercial power 
came back on, the panels would have been destroyed, and the trees that came 
down on the roof and any other mounting structure that would have held the 
cells would have blocked the ones that were still good.

No disaster plan is perfect, everything needs a backup.  I was able to run 
on generator while all my neighbors threw out all the food in their 
refrigerators and freezers and suffered one of the hottest days of the month 
without so much as a fan for comfort.  I had an ample gas supply but was 
able to refill gas jugs the second day as the local gas station wired in a 
generator they were able to acquire.



-----Original Message----- 
From: Brian B. Riley
Sent: Sunday, September 11, 2011 11:10 AM
To: TAPR APRS Mailing List
Subject: Re: [aprssig] Shack backup power

I was looking through some old posts and couldn't resist.

  … please tell this to the grid-tied people among  the 2 million who went 
without power in the American SouthWest recently or among the millions in 
the NorthEast after Irene.

Here at Wulfden I received 'help me' calls from three local homeowners with 
over 16 KW of PV between them and not a single electron flowing (or being 
credited!) even though the sun was shining quite brightly. Two of the three 
had minimal grid driven battery backups for 'bare essentials' that had long 
since run flat.

Here at Wulfden we were comfy, and cozy … water was running, lights were 
on … and I still haven't had cause to run my  generator since the end of 

  How many Nukey-Poo facilities went into programmed shutdown because they 
lost reliable power for control systems? How many were scrammed because 
rivers were beating on  their front door?

These are the 'rare' outages that were dismissed because of low probability, 
yet they happened before even a fiscal quarter had gone by since this point 
in the conversation.

  Yes, Bob, in a perfect world untroubled by extremes of weather, grid-tied 
makes sense, but if we learned any lessons from this recent bout with Ma 
Nature we would start taking greater account of outages.

On Jun 4, 2011, at 4:58 PM, Bob Bruninga wrote:

> For a shack system, designed about one's average operating load, on any 
> day when one does not fully use the shack to that average, then all excess 
> solar energy is also wasted, because the batteries have no room for 
> today's excess solar power.. (Generally).
> That's why grid-tie wins hands down.  Every penny of solar energy is 
> credited to you no matter how or when you use it.

cheers ... 73 de brian  riley,  n1bq , underhill center, vermont
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