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Re: Dealing with possible power cuts.

Posted: September 20th, 2021, 9:45 pm
by Mike4
AF62 wrote:
Mike4 wrote:My strategy is to decamp to one or another of my boats.


My strategy is just to leave the country for somewhere warmer.


Boats are toasty warm in freezing weather. Light the multifuel stove and throw open the doors to regulate the temp, lovely!

Re: Dealing with possible power cuts.

Posted: September 24th, 2021, 10:27 am
by 88V8
Assuming you have working fireplaces, as we have had in all our houses going back 45 years, there's an easy solution.

Many people seem to overheat their houses; in houses where we had CH, the stat was set at 62F/16C. Now we heat to about low 60s, a bit vague as we have storage rads and woodburners.
Also, it was routine to heat one room. Many people seem to think they should be able to wander around the whole house in their shirtsleeves. How wasteful we are.

I would be more concerned about the fridge and the freezers. I have thought about a back-up power solution with a small petrol generator, but I would run a separate feed to the appliances I wanted to keep going. Putting the power into the CU and just hoping that no one will turn on too many appliances is too woolly for me.

In practice I think the brunt of any cuts will fall on industry, or what little industry we have left. The last thing the politicos will want is voters being left with no tele.

V8

Re: Dealing with possible power cuts.

Posted: September 24th, 2021, 4:21 pm
by malakoffee
Just wondering : . . . . If one's house has grid-connected PV and the mains power fails ?
Do the home appliances still work - within the PV power limits - or is the whole lot shutdown ? [ No batteries in this simplest case. ]

Re: Dealing with possible power cuts.

Posted: September 24th, 2021, 4:28 pm
by swill453
malakoffee wrote:Just wondering : . . . . If one's house has grid-connected PV and the mains power fails ?
Do the home appliances still work - within the PV power limits - or is the whole lot shutdown ? [ No batteries in this simplest case. ]

I think it was said on an earlier thread that it must shut down if the grid goes off, to avoid the risk of electrocuting anyone trying to repair the grid.

Scott.

Re: Dealing with possible power cuts.

Posted: September 24th, 2021, 7:40 pm
by 9873210
swill453 wrote:
malakoffee wrote:Just wondering : . . . . If one's house has grid-connected PV and the mains power fails ?
Do the home appliances still work - within the PV power limits - or is the whole lot shutdown ? [ No batteries in this simplest case. ]

I think it was said on an earlier thread that it must shut down if the grid goes off, to avoid the risk of electrocuting anyone trying to repair the grid.

Scott.


It must be disconnected from the grid if the grid goes off. If you pay extra you can get a system that does that while continuing to provide power locally. Off grid operation usually involves a battery but you could certainly design a system that provides a useful amount of local power without a battery.

The cost of an isolator is much smaller than the cost of the PV or the cost of a battery. The prevalence of designs that shutdown when the grid goes down is essentially a testimony to the reliability of the grid.

Re: Dealing with possible power cuts.

Posted: September 24th, 2021, 8:05 pm
by malakoffee
^ Thanks both. . . . .

If a PV system cannot export to the grid and the owner cannot use all the energy . . . . er, where does the excess energy go ??

Re: Dealing with possible power cuts.

Posted: September 24th, 2021, 8:12 pm
by doolally
malakoffee wrote:^ Thanks both. . . . .

If a PV system cannot export to the grid and the owner cannot use all the energy . . . . er, where does the excess energy go ??

Same as asking where does the energy in a NiCad or alkaline cell go when you are not taking power from it?
Or where does all the water go if you don't turn the tap on?

doolally

Re: Dealing with possible power cuts.

Posted: September 24th, 2021, 8:20 pm
by malakoffee
For some strange reason I thought that one cannot switch-off a solar panel,
. . . . but that doesn't make sense - after all where does one dump the PV energy after the DHW is heated up to near boiling point.

Obviously something breaks the circuit and the energy has to stop . . . . . . Y or N ?

Re: Dealing with possible power cuts.

Posted: September 24th, 2021, 11:16 pm
by swill453
malakoffee wrote:For some strange reason I thought that one cannot switch-off a solar panel,
. . . . but that doesn't make sense - after all where does one dump the PV energy after the DHW is heated up to near boiling point.

Obviously something breaks the circuit and the energy has to stop . . . . . . Y or N ?

In the absence of a solar panel, the roof would get warm. In the absence of a current flowing out of the solar panel, it would simply get warm too. No harm done.

Scott.