[aprssig] backup pwr systems - slightly off-topic

[Brian B. Riley]

Having lived off grid for 18 years ... "Most on-grid systems will  
shut down" - WRONG ... EVERY grid tied system MUST shutdown if the  
grid loses power or else you don't get to tie to the grid. The reason  
is quite simple ... if you don't, you run a good chance of blowing a  
lineman off a pole somewhere trying to fix whyever the grid went  
down. The authorities and the courts would have no sense of humor on  
that matter.

Now there is whole movement of "guerilla solar" of guys doing  
surreptitious grid-ties and I have felt for years that this was  
stupid and just a disaster waiting to happen.

Personally, I have no interest in tying to the grid. I would have to  
shell out $15K to get the power lines up here and then a couple of K$  
for the grid-tie interface. I would sooner spend a couple of hundred  
for an electric hot water heater and a 24 vdc replacement heating  
element and rig it as a hot water "pre-heater" to dump my extra power  
in the summer months when I always have a surplus.



---
cheers ... 73 de brian  riley,  n1bq , underhill center, vermont
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On Dec 11, 2006, at 1:36 AM, Derek Koonce wrote:

> Bruce,
> I have looked at these systems. Most on-grid systems will shut down  
> if they detect the power grid shutting down. They will not power  
> the house in this state unless one has a battery back-up system.  
> And then the system will disconnect the house from the grid to  
> prevent "islanding".
>
> Derek Koonce
> KE6JTP
>
>
>
> Bruce Gordon wrote:
>
>> Bob,
>>
>> What you describe is exactly a grid-tie inverter, just not so  
>> large as those
>> used in all house or larger systems.  I have never seen how they  
>> protect
>> themselves and others from the hazards of tying to the grid but I  
>> can't
>> think of a reason that it couldn't be done in a smaller unit.   
>> Might burn up
>> a little of that "copious free time" however.
>>
>> Bruce Gordon
>>
>>
>
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