Electricity Maximum Import Capacity

rockabaloo

Hello, does anybody have a rough figure for a Maximum Import Capacity for electricity (http://www.nie.co.uk/FAQ/What-is-the-MIC)?

I know this will vary greatly depending on house size, number of occupants and typical usage. But does anybody have any idea of ball park figures?

sydthebeat

http://www.esb.ie/esbnetworks/en/domestic-customers/new_domestic_online_connection.jsp

the mic usually only is applicable to business connections

rockabaloo

Nice one sydthebeat, thanks for the link.

It seems that NIE want the info for domestic installs in the North too - http://www.nie.co.uk/Connections/home/When-and-how-to-apply.

rockabaloo

I just noticed this on what of the NIE application forms:

"The MIC for a standard domestic connection (without electric heating or heat pumps) is usually 18kVA."

Hmmmm, if I am planning to install a heat pump I wonder if this would be adequate?

heavydawson

rockabaloo wrote: »

I just noticed this on what of the NIE application forms:

"The MIC for a standard domestic connection (without electric heating or heat pumps) is usually 18kVA."

Hmmmm, if I am planning to install a heat pump I wonder if this would be adequate?

The HP installer will be the only person to answer that.

rockabaloo

Yup, I know. Just not ready to engage with a heat pump specialist yet but am wanting to apply for electric soon.

ECO_Mental

I think most domestic houses are around the 15 kVA mark in the Rep. This should be adequate for most houses. An electric shower will be about 7 kW, so if you had the kettle running and maybe the electric hob this should get you to around 10 kW. So you should never get to 15 kVA.

A rough guide is 1 kVA = 1 kW (it is actually kW/ power factor which should be around 0.97 but this is only for commercial max demand accounts so dont worry about it)

I am currently reducing the MIC's in our elect accounts in work and I know they are commercial (but they are general purpose night saver accounts) and you can specify the MIC up to 29 kVA and it shouldn't cost you anything extra than 15 kVA, because any thing less than 29 kVA the PSO levy is just a flat rate. Above 29 the PSO levy will be charged per kVA. That's in the Rep dont know about the north though.

Find out what the kW demand on the heat pump you might be interested in, it should be on the spec sheet. But remember the HP will be working at night when all the rest of the stuff should be off( In theory..) A big HP is around the 10 kW mark so 18 might be ok. But you will have to do the maths.

Be carefull not to over spec though. I have reduced my company's MIC by nearly 1000 kVA over the last year and now saving us €100k in annual standing charges. We had designers and engineers adding up every single plug and socket in a buildings/facilities and then adding a factor of safety as well just to be sure. But in reality this will never happen.

rockabaloo

Thanks ECO_Mental, some good info there.

The heat pump I'm looking at at the minute is a Mitsubishi Ecodan 8.5kW. So it should only draw about 4kW at the most.

I won't be having an electric shower (never realised they took so much power though!) so I reckon the standard 18 kVA should be dead on then.

fclauson

so we have just moved in - 16Kva supply - 9Kw HP (which includes 6Kw of emmersion which should never be used) - cookers etc etc

and in testing we fried the main fuse :mad:

The HP has 3 levels of emmersion - and we have set it to alarm and not turn on if it needs more than 1 - that way we can make sure we are not cooking etc etc at the same time - we expect this to happen once a millenium so that should be ok

the ESB assume you will use you HP overnight when not much else is on - in a Passive house this is not the case - our HP runs 24x7 and works out itself if it needs to come on

rockabaloo

Hi fclauson, did you get your electric problems sorted? How you finding things now?

fclauson

all sorted - HP using about 9Kw for heating per day and 5Kw for h/w

rockabaloo

Good stuff. Do you find the 16 kVa is adequate now everything has settled down?

Sounds like the pump is pretty economical to run then.

fclauson

yes - but you do need to plan how you use you electric

if I allowed my HP to kick in with its 3 steps of emmerision and I then turn on the ovens and cloths washer then I would be in trouble

so you do need to plan an be careful