Huge electricity consumption in a brand new house

hellesangel

Cardew wrote: »

4,500kWh pa for an air source heat pump providing heating and hot water is excellent - almost unbelievable excellent

We have a wood burning fire with a heat exchanger that also feeds the heating and hot water system so the heat pump just sits as reserve while the fire is lit. The heat exchanger in the fire is a great system. Some 60% of the heat from the fire goes to the central heat reserve, stops the sitting room getting insanely hot and warms everywhere else. And yes, I measured the consumption of the circulation pump, some 30 watts when it's running.

Cardew wrote: »

If you are convinced that the 20,000kWh does not include a proportion of the Heat Pump/immersion consumption, then it should be fairly easy to narrow down the culprit causing the heavy consumption. The dryer will presumably be used a great deal.

And again I'm quite sure that there is nothing for the heating or hot water drawn from our 20,000kWh meter - no immersion heater, nothing, we had an independent electrician check precisely this and we very rarely use the dryer, that would be an obvious candidate.

Unfortunately I was also expecting it to be easy to find something burning a constant 500 watts or more, so far it's confounded me. It's difficult to find a time when I'm not at work and everyone else is out so I can turn everything off for a day and work through it. It would help if I had some suggestions of what it may be. I'm less convinced it's something we plugged in, I know everything we have, more suspecting it's a faulty part of the house wiring. Any ideas what types of installation could burn this order of magnitude of power without tripping the circuit breakers?

I've ordered a Fluke 325 clamp meter which will help narrow it down more scientifically, but it's a lot of wiring to check.

hellesangel

To follow up with an order of magnitude comparison to show everyone what the scale of the problem is - jeepjunkie, posted above, has an old house, all electric, and uses 8000kWh a year. We have a modern certified low energy house with modern everything and have used nearly 15,000kWh, combining our two meters, for each of the past two years, ie. double. It cannot be right.

Rubidium

hellesangel wrote: »

I'm an electronic engineer and understand how electricity works, I'm stumped.

Are you seriously telling us that you have not performed a simple load test to prove that the meters are registering correctly?

That is the obvious first thing to do and if you can't do this yourself then your supplier will do it for you.

macman

Given the scale of the problem, I'd ask your supplier for a meter test. The £60-odd it will cost if found to be correct is small beer in comparison to your excess spend.
BTW, the supplier is only required to meter read once every two years-all intermediate reads are your reponsibility, and should be done and submitted at least quarterly. Sign up for online billing and they will send you email reminders, so impossible to forget.
Wiring faults do not seem likely: as you say, any earth leakage on that scale should trip out the RCD-which I assume your sparky has already tested and verified to be working correctly?

[Deleted User]

hellesangel wrote: »

To follow up with an order of magnitude comparison to show everyone what the scale of the problem is - jeepjunkie, posted above, has an old house, all electric, and uses 8000kWh a year. We have a modern certified low energy house with modern everything and have used nearly 15,000kWh, combining our two meters, for each of the past two years, ie. double. It cannot be right.

Hope you get to the bottom of this as something is not right...

You'd think that if there was a wiring fault there would be breakers tripping regularly/instantly with the possibility of a fire. A relatives house recently went on fire due a wiring fault. But as you say it's a new house and wiring has been checked so I would just check everything with a plug-in energy monitor. Nor can it really be an immersion as these are thermostatically controlled in a new well insulated tank...

Might be worth getting the meter checked?

Cheers

hellesangel

cameltoe wrote: »

Are you seriously telling us that you have not performed a simple load test to prove that the meters are registering correctly?

Yes, I did all the simple tests... when all fuses are off the meter stops. I'm waiting for my current meter to be delivered so I can try to verify the house meter is reading correctly, but I strongly suspect it is. As I said before, my suspicion is something in the house installation is burning a permanent ca. 500 watts.

Next step is to unplug everything and turn the fuses on one by one and see which one causes the meter to start ticking unexpectedly, then try to measure the leakage and find the culprit, but this is very time consuming and full of practical difficulties in a house with so much electrical stuff in it, hence my request for hints.

macman wrote: »

Wiring faults do not seem likely: as you say, any earth leakage on that scale should trip out the RCD-which I assume your sparky has already tested and verified to be working correctly?

I don't think it could be a simple leak to earth, the ELCBs are working correctly, more a mis-wired device that is permanently burning power. I heard of one electrician who fitted a load across the mains line to help smooth the flicker that you sometimes get when dimming LED lights. It did work for that, apparently, but it permanently burned power.

Robin9

There isn't really much difference between jeepjunkies 8000Kwh a year and your 20000Kwh in 2 (ie 10000Kwh in onw)

except perhaps jeepjunkie hasn't got baby twins ?

My own house is has heated by gas but still consumes 6000kwh of electric a year

So much depends on your lifestyle

molerat

Have you been taking daily reads ?
Do you know the meter read from when you moved in ?

hellesangel

Robin9 wrote: »

There isn't really much difference between jeepjunkies 8000Kwh a year and your 20000Kwh in 2 (ie 10000Kwh in onw)

There is a significant difference - jeepjunkies' 8000kWh reading is for everything, our 20,000kWh over 2 years reading excludes everything for the heating and hot water.

The meter was at an incredible 5904kWh when we moved in. At the time I didn't think it odd, just thought the builders had had an industrial dryer in the house for a while, but had I worked it out it would have been an awfully big dryer.

enator

We have a similar setup, except the bulk of our heating is by oil topped up by heat pumps. Changed all lights to LED & bought 'A' rated appliances - despite this we still use 10,000 Kw in a year.

Our average oil consumption adds another 18,000 Kw, so 28,000 total compared to your 15,000 - I don't think you are doing too badly.

Our Heat Recovery system runs 24/365 and uses 135 watts, over a year thats 1,183 by itself, so c12% of our overall usage. You should check what yours is using.

Finally, I think you should calm down a bit