So now I have a solar PV system how do I make the most of it???

EricMears

nobby1963 wrote: »

Hang on ....Bluetooth - that means you are at home and seeing the output I guess ?

I imagine he's using Bluetooth to get data from inverter to his local computer then uploading it from there to a webpage (and reading that from somewhere else).

orrery

EricMears wrote: »

I imagine he's using Bluetooth to get data from inverter to his local computer then uploading it from there to a webpage (and reading that from somewhere else).

If you have the local computer turned on, then you can use Teamviewer (free for personal use) to view it on a remote PC or smartphone.

bris

Martyn1981 wrote: »

Ich, can I ask a question, and I hope it's not too general, nor too stupid. But why does some of the grid run as high as 250+?

I appreciate you explained earlier that voltages will vary with location, especially if it needs to be high at the start to 'pump' it to the end. But is this completely normal and correct, or does it reflect the condition of the UK grid?

Do we have a reasonably good quality grid, and these things are normal, or are there ways to level out supply? Be patient here with me, but can cable upgrades/sizing and local transformers be used (I appreciate at a cost) to bring voltages down. If not to 230V, then at least closer to the mark. Should these issues be addressed anyway, or is it widely accepted/approved to be running near the 253V limit?

Apologies for all the questions, but we're supposedly never too old to learn.

Cheers.

Mart.

It's only really the UK that is so inefficient when it comes to the grid, my supply is constantly pumping out 248v, when everything in the house can only use 220-230v. This causes us to burn money using power we don't need, that dissapates as heat in our appliances, and can cause them to fail short of their intended lifespan.

There is a product that has now been brought to the attention of the green brigade which will be sold the same way and by the same sellers of the solar panels. My fitter has told me there will be a big push on them soon, as they can save up to 18% on our electricity bill, tested and verified apparently.
It is a transformer that drops the voltage delivered from the grid to the house supply from what comes in to 230v, this stops the waste before it gets to the appliance, it promises cheaper bills and longer lifespan for our electrical goods.
It's called the voltis home optimizer (google it), there are other devices like it but apparently this is the daddy, it's got me interested, but I will wait till the reviews come in.

John_Pierpoint

Isn't the reality that the UK had a standard of 250V (as inscribed on all my old plugs) until we joined the Common Market?
Now we pay lip service to the 230V standard, and our "DNOs", usually foreign owned, are only to happy to maximise profit by flogging us 9% more power that we need or want?

What is the incentive to improve or replace such a system ?

I am the last house for about 10 miles on my network (One of the "tails" on "my" transformer came adrift in a gale and wrapped itself round the other one - that triggered all the circuit breakers from Basildon back to the Thames side (Just as a feral delinquent hammered a 6" nail into the cable on the railway bridge at Tilbury and turned my lights off).

My inverter constantly scrolls information about its environment and the lowest reading for grid voltage, I have ever seen, is 248V. It is usually more like 254V. The inverter gives two figures, one the current fluctuating value (ie 254 -> 255 -> 254 etc.) and the other gives the average for the day up to now.

Just help me over heat and burn out my inverter, thanks you Hong Kong power company.

Cardew

bris wrote: »

It's called the voltis home optimizer (google it), there are other devices like it but apparently this is the daddy, it's got me interested, but I will wait till the reviews come in.

There have been a number of threads about voltage optimisers.

The savings suggested on their websites are extremely optimistic; the 'voltis' suggests up to 17% - the dreaded 'up to'!!!!

Unfortunately Ohms Law still applies! So lowering the voltage, lowers the heat output, dims lights etc.

Obviously there will be savings, but the jury is out on whether the savings in a domestic property justify the expenditure of fitting these devices.

orrery

The argument relating to voltage isn't that simple.

Many appliances have switching power supplies and will simply adjust for the difference - reducing the current they take in proportion.

Bulb brightness (and reliability) will vary with voltage - some of the energy saving ones may incorporate switching supplies and try to maintain constant voltage.

Washing machines may well control rotation/spin speeds in the same way.

All recent computer equipment with the standard power brick arrangement don't care what the voltage is, they'll take the same power whatever. I had one rechargeable razor which was happy with a supply voltage of anywhere between 12 and 250V, AC or DC.

So, all this may impact on the effectiveness of the voltage reducing devices which are now being discussed.

EricMears

John_Pierpoint wrote: »

Isn't the reality that the UK had a standard of 250V (as inscribed on all my old plugs) until we joined the Common Market?

No. We had a standard of 240V and a margin of error (possibly 6% ?). A 250V marking on the plug probably indicates that it's been tested at 250V to make sure it works OK at 240V & normal fluctuations. Just as mains cables (whether you call them 220, 230 or 240V) are usually tested at 600v (so too are 110V cables).

bris wrote:

There is a product that has now been brought to the attention of the green brigade which will be sold the same way and by the same sellers of the solar panels. My fitter has told me there will be a big push on them soon, as they can save up to 18% on our electricity bill, tested and verified apparently.

There is indeed such a product but it won't save you 18% "on your electricity bill" ! It might save you 18% on some devices (that don't use a lot of power anyway) which work quite happily at 220V and no better at 250V. However, any heating applications (heavy power users) would probably save 18% of power but have to run 18% longer to deliver the same amount of heat. Even some electric motors might give you a benefit by running at higher power (e.g. more power from a vacuum cleaner = more 'suck' = less time to clean a room). Overall saving "on your electricity bill" will therefore be very much less than the claims.

The device that might offer this alleged saving isn't exactly cheap. I understand there are several contenders but all cost the thick end of £1000 by the time they've been fitted; interest on that probably wipes out most of the actual savings.

grahamc2003

John_Pierpoint wrote: »

My inverter constantly scrolls information about its environment and the lowest reading for grid voltage, I have ever seen, is 248V. It is usually more like 254V. The inverter gives two figures, one the current fluctuating value (ie 254 -> 255 -> 254 etc.) and the other gives the average for the day up to now.

Just help me over heat and burn out my inverter, thanks you Hong Kong power company.

You should complain to your dno if your voltage is ever 254V or more. The Uk limits for supply voltage is 217-253V - if your inverter can't handle up to 253V safely and efficiently, then it's not fit for the UK market. Of course, the inverter's accuracy may give a reading of 254V when it is actually below than and in spec. Others who know the local grid have posted about the problems of maintaining an in-spec voltage to everyone on the local network - like many things, I expect there are compromises to be made - nevertheless, for pragmatic reasons, if your inverter spec says the supply voltage must be at or below 253V, and yours is always hovering around there, I'd get the dno involved anyhow.

I wouldn't worry about your supply being around the higher limit for cost reasons - I doubt you'd save anything significant even if your supply was at the lower limit of 217V.

John_Pierpoint

Thanks for the correction about the old standard being 240V not 250V.
I have rechecked 28 "spare" plugs in a drawer in my shed.
When did sheathing the live/line/phase and the neutral prongs in black plastic become mandatory? Probably after lighting circuits acquired earth wires and the cable went from stranded to single wires ? Anyway if they mention voltage they all say 250V, and the greater majority of the 28 do. All of them say BS1363 except one that says "Empire Made" and one that has round prongs :rotfl:

I have a funny feeling that for many hours of the day it is only me that is actively attached to the national grid via my local "up the pole" transformer. The major user is street lighting on a national highway, so my inverter is turned off when that is turned on.
I don't think I will stir things up with the DNO, they might turn round and accuse my inverter of overloading the local voltage - The local DNO operates out of premises in "Darkes Lane".

Brilliant address for an electricity provider.;)

davidanddeirdre

Question for you techno wizards out there. As I understand it, electricity is pretty fluid in a good conductor like a mains cable. Presumably therefore, if one feeds a voltage into a mains cable which already has electricity in it coming along the other way as it were, as one is from a PV inverter, the voltage of that fed in electricity will immediately adjust itself to, or possibly infinitessimally higher than, the mains line voltage, any surplus being exported at that infinitessimally higher voltage? (My inverter gives a spot reading updated every 15 secs or so and fluctuates around 235V, which seems perfectly reasonable).
How I visualise it is like pouring water into a tank, when the added water does not sit on previously added water in a pile, but immediately levels itself out. It will raise the level, but if the amount added is very small compared to what was there already, as would be the case from a household PV inverter to the grid, the increased level will also be very small.
Does this make sense?