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pedg

100A fuse upgrade: meter to consumer unit?

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pedg

Hopefully this is the right place to ask this question. Apologies if not.

 

We need to get our 60A main fuse upgraded to a 100A fuse to handle the addition of battery storage and EV charge point.

 

Due to various rules it appears we need someone from the power supply company, someone from the people we are buying electricity from and our own electrician there at the same time as each is only allowed to change things in their own areas?

 

What power company and provider need to do is, I think, clear, if perversely over-regulated (provider adds bigger wires to the meter so that power company person can connect them to new fuse). My confusion is about what I need our electrician (once we can get hold of one) to do? Power company says they would need to upgrade cable between the meter and the consumer unit but our current set up is more complicated than that.

 

(apologies if not using the right terms).

 

Currently meter goes to a junction box where the solar PV comes in. Then another ongoing cable goes, via an 80A RCCB, to a second junction box. Off this are the main consumer unit,  subunit for the outhouse and currently redundant connection which we hope to use for the battery and EV connections.

 

My guess is that we need to upgrade the cable from meter to first junction box, the cable from that junction box to second junction box and the RCCB with something that can handle a higher amperage. Beyond the second junction box none of the things connected should be drawing anything near 100A individually so would hope/assume not of the other wires need upgrading?

 

So question is what do we need to get an electrician to do to appease the power supply company (UK power networks as in Cambridge)?

 

Thanks for any help.

 

 

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Murdoch

I think you need to get a local spark or 2 to advise you

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Phoenix

Any chance of some pictures?, I think as a new user here, you'll have to upload them somewhere on the www and link them here as I dont think you can upload to here until you have x amount of posts....

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ProDave

I am not sure why your energy supplier needs to be involved in the mix.

 

FIRST thing is your spark upgrades the outgoing meter tails to your consumer unit(s) and ensures all of that is up to standard.  That will involve cutting the seal on the meter (if there ever was one).

 

Then the DNO will come and upgrade the tails from their supply head to the meter and re seal everything.

 

They don't need to be there at the same time,  in fact that would be a bad plan as the DNO is not going to wait around for your electrician so he can re seal the meter.

 

That's how it would work here in SSE land, I know some other DNO's have other ideas.

 

There are some ways to make it work easier.  A good one here is don't mess about trying to ask for upgrades.  Get your electrician to do your tails, then your electrician phones the DNO and reports a dangerous condition (note the D word) reporting substandard tails.  That will usually get them out quick.

Edited by ProDave

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pedg
2 hours ago, Murdoch said:

I think you need to get a local spark or 2 to advise you

I am trying to but want to get a better handle on what to ask them.

 

1 hour ago, Phoenix said:

Any chance of some pictures?, I think as a new user here, you'll have to upload them somewhere on the www and link them here as I dont think you can upload to here until you have x amount of posts....

Tails from meter go into this block that links in the solar: https://photos.app.goo.gl/dmnWKoQUN3Njk6HHA

Ongoing cable goes through this RCCB: https://photos.app.goo.gl/KyDwMWit95uasE6o6

Into this block that then goes onto consumer unit, sub unit, etc: https://photos.app.goo.gl/at2Rtuq62Q3v2zBW9 (I paraphrased a bit as currently have one spare (old shed connection), one now used for solar bypass, (old power show connection). Plan is to combine this into one subunit with the battery and EV connections)

 

1 hour ago, ProDave said:

I am not sure why your energy supplier needs to be involved in the mix.

 

FIRST thing is your spark upgrades the outgoing meter tails to your consumer unit(s) and ensures all of that is up to standard.  That will involve cutting the seal on the meter (if there ever was one).

 

Then the DNO will come and upgrade the tails from their supply head to the meter and re seal everything.

 

They don't need to be there at the same time,  in fact that would be a bad plan as the DNO is not going to wait around for your electrician so he can re seal the meter.

 

That's how it would work here in SSE land, I know some other DNO's have other ideas.

 

There are some ways to make it work easier.  A good one here is don't mess about trying to ask for upgrades.  Get your electrician to do your tails, then your electrician phones the DNO and reports a dangerous condition (note the D word) reporting substandard tails.  That will usually get them out quick.

Apparently, as I understand it, the power distribution company own the fuse, the energy supplier owns the meter and we own everything after the meter. UK power networks appear to be more fussy than others about this from what i can see.

 

Also my question is that the meter tails do not go directly to the consumer unit and in this situation which parts need to be upgraded?

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Sharpend

What area are you in? 
 

all you need is to ask a local spark - ask work colleagues, family neighbours who they have used - if they will take a look to see if your existing meter tails need upgrading for a 100A supply. Leave the rest to the spark to advise. Shouldn’t take that long to do if he/she is competent. 
 

then arrange for DNO to carry out upgrade of their cabling if required, as Dave hinted at there are ways to get it done pronto if it’s not already prearranged. The DNO may well upgrade the fuse for you at same time, although not always. It’s more about who comes out. 
otherwise you will have to request the upgrade from the DNO in which case there may be a charge? 
 

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ProDave
8 hours ago, pedg said:

 

Apparently, as I understand it, the power distribution company own the fuse, the energy supplier owns the meter and we own everything after the meter. UK power networks appear to be more fussy than others about this from what i can see.

 

Also my question is that the meter tails do not go directly to the consumer unit and in this situation which parts need to be upgraded?

There is no consistency in supply companies.  the worst I found was N Power who would not take a telephone report of an urgent dangerous condition and demand I put the request in writing.

 

As to which part of your tails to upgrade.  ALL of them should be upgraded to 25mm. It might be a good opportunity to get rid of some of the junctions and tidy things up.

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binky
11 hours ago, pedg said:

 

 

We need to get our 60A main fuse upgraded to a 100A fuse to handle the addition of battery storage and EV charge point.

 

Thanks for any help.

 

 

 

Battery shouldn't affect main incoming supply, not so sure about EV charge point, but I'm interested to know who said this? 

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pedg
5 hours ago, Sharpend said:

What area are you in? 
 

all you need is to ask a local spark - ask work colleagues, family neighbours who they have used - if they will take a look to see if your existing meter tails need upgrading for a 100A supply. Leave the rest to the spark to advise. Shouldn’t take that long to do if he/she is competent. 
 

then arrange for DNO to carry out upgrade of their cabling if required, as Dave hinted at there are ways to get it done pronto if it’s not already prearranged. The DNO may well upgrade the fuse for you at same time, although not always. It’s more about who comes out. 
otherwise you will have to request the upgrade from the DNO in which case there may be a charge? 
 

In Cambridge so UK power network the DNO. Tried a number of sparks but most end up at the 'We will get back to you" stage that never happens and with various things a bit up in the air I have not got round to rehassling any of them but will try again.

4 hours ago, binky said:

 

Battery shouldn't affect main incoming supply, not so sure about EV charge point, but I'm interested to know who said this? 

You can charge the battery from mains as well as from the solar. Obviously only really of use if on a variable tariff. Intending to move to octopus agile tariff so on the rare times they pay you to use electricity could well be wanting to put 16A into the battery and 32A into the EV at the same time.

 

Basically I think my question best asked as 3 separate questions:

 

1) How much of the wiring would need to be upgraded to 25mm for the DNO to be happy given I don't have wires going directly from the meter to consumer unit? Given max current from each branch from the final junction box would be under 60A individually assume 25mm through to that junction box should be fine?

2) Can I get a spark in to do the upgrades from the meter onwards before the other changes? (supply company promise to attend at the same time as the DNO to do their bit). 

3) What should I have the 80A RCCB replaced with?

 

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Murdoch

If you get up to 10 posts you can post pictures ............

3 hours ago, pedg said:

I3) What should I have the 80A RCCB replaced with?

 

 

 

That rather depends on the size of the DNO fuse ..........

 

 

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pedg
1 hour ago, Murdoch said:

If you get up to 10 posts you can post pictures ............

 

 

That rather depends on the size of the DNO fuse ..........

 

 

Going from a 60A fuse to 100A fuse so current 80A RCCB one assumes is going to be too small.

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Murdoch

find a local spark

 

Given how slow the DNO's work - you may have up to 12 weeks to find one.

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binky
6 hours ago, pedg said:

 

You can charge the battery from mains as well as from the solar. Obviously only really of use if on a variable tariff. Intending to move to octopus agile tariff so on the rare times they pay you to use electricity could well be wanting to put 16A into the battery and 32A into the EV at the same time.

 

 

 

OK so it's an AC battery set-up, and you are looking for the potential to charge battery and EV on off-peak tariffs, when it is unlikley you will be pulling any other large loads unless you have night storage heaters. Probably find 60A main fuse is fine as it is. If you wanted a bit of extra headroom, replace with 80A, that way, and I'm guessing your existing tails are16mm,  everything else would be fine as they are. 

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pedg
19 hours ago, binky said:

 

OK so it's an AC battery set-up, and you are looking for the potential to charge battery and EV on off-peak tariffs, when it is unlikley you will be pulling any other large loads unless you have night storage heaters. Probably find 60A main fuse is fine as it is. If you wanted a bit of extra headroom, replace with 80A, that way, and I'm guessing your existing tails are16mm,  everything else would be fine as they are. 

Actually with the Agile tariff the cheapest periods are often mid-afternoon before peak period starts at 4pm (usually), which makes it useful for topping up the battery before the peak period (e.g. see today's here: https://twitter.com/energystatsuk/status/1285594671645970433/photo/1). Also for the occasional periods when the tariff goes negative, i.e. you are paid to use the electricity, would like to have enough overhead to do things like have the washing machine, tumble drier, dishwasher etc on at the same time to make the most use of it.

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apprentice87

Hmm,

 

Hate to say this, but before you get too carried away, it is VERY far from certain that the DNO will give you a bigger supply...

 

john..

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SPECIAL LOCATION
1 hour ago, apprentice87 said:

Hmm,

 

Hate to say this, but before you get too carried away, it is VERY far from certain that the DNO will give you a bigger supply...

 

john..

 

When we last had our meter replaced they also downrated the main fuse from 100A to 80A...

Which is around about 18.5kVA...

 

 

I asked why, they basically said it was now routine policy not to fit 100A to a standard domestic installation...

 

Guinness   

Edited by SPECIAL LOCATION

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Sharpend

Most new builds were fitted with only a 60a fuse and that was going back a good few years, apparently a house wouldn’t exceed this. 

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pedg
11 hours ago, apprentice87 said:

Hmm,

 

Hate to say this, but before you get too carried away, it is VERY far from certain that the DNO will give you a bigger supply...

 

john..

 

Their website here https://www.ukpowernetworks.co.uk/electricity/fuse-upgrade appears to imply its a standard operation but possibly not then? As it says " Our expert will visit you to advise what is possible at your property." I have messaged them to get someone out to look at it to see what they say. 

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binky
17 hours ago, pedg said:

Actually with the Agile tariff the cheapest periods are often mid-afternoon before peak period starts at 4pm (usually), which makes it useful for topping up the battery before the peak period (e.g. see today's here: https://twitter.com/energystatsuk/status/1285594671645970433/photo/1). Also for the occasional periods when the tariff goes negative, i.e. you are paid to use the electricity, would like to have enough overhead to do things like have the washing machine, tumble drier, dishwasher etc on at the same time to make the most use of it.

 

Not looked at tariffs for a long time, very interesting and all part of the 'smart network' they have been talking baout for years. Even with all the appliances running you are unlikley to top 80A - your solar panels wil help with that.. The main fuse will take some temporary power spikes at higher than 80A for shortish periods of time. Things like washing machines when not heating water will run at around 250W, so I would feel 80A is probbaly fine.  John is correct though, they won't necessarily give you 100A as it depends on the house feed, but only the local DNO can advise you of that. Around my way, 80A is normal, and I have 60A being an older house. 

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pedg
3 hours ago, binky said:

 

Not looked at tariffs for a long time, very interesting and all part of the 'smart network' they have been talking baout for years. Even with all the appliances running you are unlikley to top 80A - your solar panels wil help with that.. The main fuse will take some temporary power spikes at higher than 80A for shortish periods of time. Things like washing machines when not heating water will run at around 250W, so I would feel 80A is probbaly fine.  John is correct though, they won't necessarily give you 100A as it depends on the house feed, but only the local DNO can advise you of that. Around my way, 80A is normal, and I have 60A being an older house. 

 

Interesting thing about these tariffs is it makes having a battery system a viable option even for those people without solar as you can cover the expensive period by timeshifting power from a cheaper period that will take 30 to 50% off the electricity bill. For us the combination of summer savings via the solar and winter savings via timeshifting power means it will pay for itself several years sooner than just via the solar, the duration of which was what had been putting me off beforehand. My rough estimate brings it down from about 12 years to 8 but will not know for sure until it's (eventually!) used in anger.

 

I think I am moving towards the 80A option. Once the battery system up and running will be able to better monitor energy usage via its CT clamp on the main cable so will be able to see how high it does go (current 'smart' meter has self lobotomized itself so of no use at the moment). For the AC inverter I have there is some software that both reports current data and allows it to be controlled programmatically. Was going to use this to try and automate when it charged from the mains but probably sensible when it is set to do that to keep an eye on the power been drawn from the grid so it can I can turn it off again if the current gets close to 80A.

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ProDave
7 minutes ago, pedg said:

 

Interesting thing about these tariffs is it makes having a battery system a viable option even for those people without solar as you can cover the expensive period by timeshifting power from a cheaper period that will take 30 to 50% off the electricity bill. For us the combination of summer savings via the solar and winter savings via timeshifting power means it will pay for itself several years sooner than just via the solar, the duration of which was what had been putting me off beforehand. My rough estimate brings it down from about 12 years to 8 but will not know for sure until it's (eventually!) used in anger.

 

I would like to see that properly costed.

 

Every time I look at battery storage, on the basis of using it to charge with free electricity from my solar PV for use later, I keep finding that the payback time is so long, the batteries are probably in need of replacement by the time it has paid for itself.

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pedg
2 minutes ago, ProDave said:

I would like to see that properly costed.

 

Every time I look at battery storage, on the basis of using it to charge with free electricity from my solar PV for use later, I keep finding that the payback time is so long, the batteries are probably in need of replacement by the time it has paid for itself.

 

I ran some simulations a while back based on historical agile data and my solar data. Obviously contained a number of assumptions so not sure how accurate it would be in terms of calling it 'properly costed'.  Possibly some of the more interesting graphs on that site are the long term max, min and average cost ones (like this one on this page for the east of England https://www.energy-stats.uk/octopus-agile-eastern-england/) which shows that there has been a gradual downward trend on all 3 over the last year, though has levelled off more recently. When I set my simulation to use the data from the last 90 days rather than the last year it reduced the payback time by about a year. For info I got (and obviously still trying to get installed!) a LUX - LXP3600 AC Controller and 3 Pylon Tech 2.4Kw US2000 Lithium Batteries (plus delivery) for £3192.

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ProDave

So that's 7kWh of battery storage.

 

Say I had that much spare from my PV otherwise going to waste and I could use that in the evening, that would offset £1 of electricity usage each day.  So that would take 3192 days or 8.74 years to cover the equipment cost.

 

Of course it would take at least double that in real life because there won't always be that much spare PV. So 17 years.  How good do you think the batteries would be by then?

 

If you can "buy" the power in for £0 at the right time and use it to offset in the peak period on the agile tariff when it might be 30p or more then it just might begin to make sense.

 

Can you program it when to charge and when to discharge based on time of day to match the agile tariff?

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pedg
8 minutes ago, ProDave said:

So that's 7kWh of battery storage.

 

Say I had that much spare from my PV otherwise going to waste and I could use that in the evening, that would offset £1 of electricity usage each day.  So that would take 3192 days or 8.74 years to cover the equipment cost.

 

Of course it would take at least double that in real life because there won't always be that much spare PV. So 17 years.  How good do you think the batteries would be by then?

 

If you can "buy" the power in for £0 at the right time and use it to offset in the peak period on the agile tariff when it might be 30p or more then it just might begin to make sense.

 

Can you program it when to charge and when to discharge based on time of day to match the agile tariff?

 

You can. One of the reason I went for the model I did is someone has written an automated program to do that for you. Even if you can't buy at zero, if the lowest if 5p say, the average outside the peak period is 9 and the peak is 20. If you load the battery up (if needed) at 5p and discharge during the 20p peak you are going to be paying about 8p per kwh average for the day. Add that saving into that for the stored solar and its pays off a lot quicker. After a while the capacity of the batteries will drop but my thought there is that at that point I can probably get hold of a similarly used battery for a few hundred quid, add that in parallel with 3 I have and get back to close to the original capacity. The other point for us is that the variable tariff is good for charging an EV so that throws in some more savings and the battery means we don't have think too much about what electricity we are using on what in the peak period.

 

On the subject of the original question I have managed to arrange for a local spark to come and visit next week so I think I will mark the first suggestion to just get a spark in as the answer.

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binky
20 hours ago, ProDave said:

I would like to see that properly costed.

 

Every time I look at battery storage, on the basis of using it to charge with free electricity from my solar PV for use later, I keep finding that the payback time is so long, the batteries are probably in need of replacement by the time it has paid for itself.

batteries have vastly improved with the move to Lithium. Payback tends to be long as most people will only discharge the battery once a day, which usually returns about 12 years as a payback when I do some rough numbers. However, with an electric car to flatten the battery. the number of cycles per day could easily be 2 ( but not in winter) , so payback would then be 6 years, but then if you can charge the car battery, does it make sense to have the AC battery?  To me, batteries really suite people who just hate the energy companies and are prepared to pay as little as possible to them, but the numbers are getting better all the time.

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Murdoch

^^ lithium has problems such as its a very finite resource, coming from not so friendly countries

 

 and it can’t really be recycled properly yet

 

 fuel cells anyone?

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