Viewing 19 posts - 1 through 19 (of 19 total)
  • How much power do I need?
  • stevomcd
    Free Member

    Need to spec the electricity supply for a house I’m renovating. Really don’t know how much to go for. Can anyone suggest a figure for a typical 3-bedroom house or a good source of further info?

    Likely to have electric water-heating and maybe electric under-floor space heating (if not, then hot water underfloor with electric water-heating).

    wrightyson
    Free Member

    Firstly why can you not use the existing service as its just a renovation?
    A standard single phase new service will be 100 amp which would surely be more than enough but you will have to apply and therefore there is a cost implication!

    stevomcd
    Free Member

    wrightyson – it’s a barn conversion, bit more than just a renovation!

    The current property owner is actually responsible for installing the power so cost isn’t really an issue (for me!) just need to spec how big it is.

    More or less than 12kW (~52A) seems to be important to the planning people.

    In France BTW.

    wrightyson
    Free Member

    Aaaahh!!. Well I’ve just done 5 houses and each one has a 100amp supply. I would suggest you need that as a minimum but the loadings of electric water heaters can be high. If you then have several of these plus say electric hob and electric showers etc you may need a bit more juice!! I suggest you really need to spec you’re estimated maximum loadings now, then base it on that. Chances are all these different things wouldn’t be used at the same time but I’d suggest a little more than required power wise is the better option.

    freeagent
    Free Member

    I’d try to work around 100A max – any bigger and I reckon the costs for installation from your Energy company will start creeping up.

    dr_adams
    Free Member

    Well…
    in the uk the standard now is 100amp but there are a lot of older properties with 60amp main fuse from days gone by… that haven’t got problems. There is no difference in the supply but just what safety rating they have, i would say 52A would be too low for a barn conversion given there is maybe a bigger demand for electricity but it would also depend on if you have gas heating and cooker. Also once its in it might limit future development?

    Bear
    Free Member

    Why are you thinking of using electricity for heating, especially underfloor? Very expensive to run in this country so can’t think that will change in France.

    stevomcd
    Free Member

    Bear – no mains gas here. Will be using wood-burner to help heat water and to provide space heating, plus possibility of installing a GSHP in the future.

    Had a good browse through the Electricité de France site and there is a massive jump in the standing charges for a supply bigger than 18kW (~80A) so I think that’s what we’ll go with.

    Bear
    Free Member

    Biomass boiler.

    stevomcd
    Free Member

    Too much of a pain in the t*ts and takes up too much space.

    Bear
    Free Member

    Not really. It’s a boiler. It does require a bit of room but nothing too tricky. Get one that is also a fire and do away with wood stove.

    stevomcd
    Free Member

    It’s not the boiler that takes up space, it’s the pellets. Have spoken to a few locals that use them and they all reckon you have to dedicate a whole room to the system.

    Bear
    Free Member

    Depends on the size of the appliance. Google Firewin. Could use one of those that doubles as a woodburner?

    benw
    Free Member

    12kw is loads, i don’t think they use electric showers in france do they? it will either come off your combi boiler or direct from your water heater which will be somewhere between 1400 and 1700 watts. the only thing would be the electric underfloor heating if you go with it that could use a bit so i would ask a local electrician for what that would use under normal conditions.modern installations are well divided in france and the chances of you using 12kw in one go are very slim.here in italy between 3kw and 6kw is what you are given after that its three phase and the price goes through the roof.

    igm
    Full Member

    Where are you guys getting 100A supplies? ‘Cos we’re only putting 60 or 80A fuses in the cut-outs at Northern Powergrid* – unless someone’s not doing what they’re meant to.

    As I recall a 100A cut-out is standard, but it comes with an 80A fuse. We only do 100A single phase LV for Network Rail.

    Still, you’ll get up to 250V from us so say 15kVA – which is loads until you want a heat pump and an EV.

    *Yorkshire and the Northeast, YEDL & NEDL, YEB and NEEB if that helps.

    igm
    Full Member

    Sorry – to answer your question 80A, even at feeble euro-volts, will be fine for 95%+ of all houses. I would be very surprised if you need more.

    wrightyson
    Free Member

    Yup 100a supply fused down to 80a but the supply is still 100a. That’s western power even tho we couldn’t be any more middle of the midlands!!!

    igm
    Full Member

    Fair enough – I’d call that an 80A supply, because that’s what it will actually supply. The cut-out is 100A and the cable is probably more still; but that’s good because you’d like the fuse to blow before the assets overload.
    Until recently we were putting in 60A fuses still.

    saladdodger
    Free Member

    Ah but you are in France

    Bet ya you have a 3 phase supply what is each phase fused to iirc my place in france is fused to 40amps per phase

Viewing 19 posts - 1 through 19 (of 19 total)

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