is 100A sufficient

[JeffV]

Apologies if this question sounds stupid.
In our house we have 60A supply (or I should say, a 60A fuse on supply). We are building a largish shed in our garden that will have a 12kw heater plus lighting and a power socket for whatever bits and pieces (all fairly low power) that we might decide we want to plug in (e.g. electric drill, TV etc). I know a little bit about electrics but will get a professional in to do the job. I just wanted to have an idea in advance as the electric company have said it might be 12 weeks to upgrade our meter fuse from 60A to 100A, so I want to think ahead.
If I understand correctly, a 12kw heater will use 50 A. Does this mean that 100A will definitely not be enough - I doubt we are using the full 60A now. Or would I be better to fit just a 9kw heater?
There's no charge apparently to have the supply fuse upgraded from 60 to 100A but there is a really long lag time. So if 100A is likely to be enough, I thought it would be an idea to put the order in well in advance of waiting for the electrician to visit site (that cant be another few weeks due to holiday, etc).
Many thanks

 

[JohnD]

...a 12kw heater..

What is this 12kW heater? A smelting furnace?

p.s. I bought myself one when I retired from my job at the Brinks-Mat warehouse at Heathrow

 

[stargazer]

We are building a largish shed in our garden that will have a 12kw heater

Use suitably rated cable and supports to take power to your new shed

 

[JeffV]

Ha ha, let me explain - I intend to put in a hot tub, etc. with the cable underground.

 

[ban-all-sheds]

60A won't be enough for everything.

100A might.

If it costs you nowt you might as well order it - if your electrician eventually says you can't have a 12kW hottub, you've lost nothing.