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Power shutoffs

HarryA

Jan 22, 2017
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If you have solar cells on your roof and you are putting the power onto the grid what happens when the power company shuts off the power as in California? No power for you?

If one has an electrical automobile and charged it off the cells one could always steal power from it?
Good excuse to buy a Tesla :)
 

Tha fios agaibh

Aug 11, 2014
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When utility co turns off power, the lines are isolated and your electric meter shouldn't register any current flow. You are then off grid, but you still have your solar system in operation to supply your house.

Do you mean tapping off your e-cars battery to supply power to your house?
You could, but your only stealing from yourself.
 

shrtrnd

Jan 15, 2010
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I'm in Arizona, next door to CA.
What I'm hearing is, that most of the solar panels people install are tied into the local power company grid.
That means only those who have chosen to have it installed (wired) so that your house will operate on the solar panels if the
local electrical grid goes down, will have power ...and you will have no power at all when the sun goes down if you don't
have battery back-up for your panels.
There are lots of installers, and some local programs that subsidize solar panel installations, but they vary.
As for the electric cars, when the grid is down, you can't charge them.
If you tried to draw power from the car battery packs you better hope nothing goes wrong, because that'll void the warranty on them.
 

BobK

Jan 5, 2010
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Typically, grid tied systems do not supply power when the grid is down. I asked about that when someone came out to evaluate our house for a solar installation of that type.

Bob
 

Tha fios agaibh

Aug 11, 2014
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To me the appeal of solar, is being self sufficient and not relying on the utility co.

I understand people avoiding battery banks and the maintenance involved, but I would never want a system that I couldn't utilize myself.

I would just use a transfer switch when the grid is down to switch over to my solar.
 

shrtrnd

Jan 15, 2010
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The problem I hear about in Arizona, is that utilities and local government offer subsidies to homeowners to install solar panels.
To get the subsidy, you conform to the rules attached to the installation:
The panels are tied into the local power grid, you don't get the option to run your house off the panels, as they are supplying their output to the power company. You are offered a discount rate because your panels are tied into the power company grid, but the
panels are legally the property of the power company, and must be installed to their specifications. After 20 years, the amount of
time most solar panel manufacturers rate their panels for efficient output, THEN the panels belong to the homeowner.
As BobK mentioned, be wary when dealing with these 'freebie' solar panel schemes. I also, would only buy them independently,
as I would want the benefit of solar electricity for me, not the local power company.
Most everybody here considers the possibility of solar panels because of the sunlight available, the pros and cons of benefits need to be investigated before a commitment. The 'freebie' program is probably ok with a lot of people, but might not be for others.
 

Tha fios agaibh

Aug 11, 2014
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Interesting. I would guess that because of the expense, most would opt for a contract to finance the cost. In that case, its understandable that the utility would own the equipment. Similar to how I don't own my leased van.

As far as the connection rules, most areas of USA adopt the national electrical code.
The Nec covers everything beyond the utility point of attachment which is usually the service conductors before the meter. In other words, everything in the house is under those rules and the utility has no say so.
There could be local amendments in addition to it, but you still have the right to have your own solar system on standby.

If the grid goes down, you can bet that some would tap utility solar panels, regardless of the rules.
 

Bluejets

Oct 5, 2014
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The reason grid tie solar shuts down when the grid is down, is to prevent feedback into the grid and causing havoc for earthed out lines and maintenance crews.
Start fiddling with that setup could find you staring out at the world through steel bars for quite some time.
If you want a solar battery charger for your car, best move, buy one.
 

HarryA

Jan 22, 2017
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I gather that when you supply power to the grid you are selling your power wholesale and buying it back retail.
For 335 KWH I pay 05.1980 cents per KWH or 17.41$ for the electricity. The total bell is 52.36$ or 15.62 cents per KWH.

If one sold 100 KWH to the power company at say 3.5 cents wholesale that would be 3.50$
Even if one sold all 335 KWH that would be only 11.72$ Does that make sense or is my math wrong?

For my Tesla I will go with the "pickup":
https://www.cnn.com/2019/11/22/cars/tesla-cybertruck-electric-pickup-truck/index.html
 
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