Investigation on massive electricity bills

[sparky1508]

Hi all,
This morning I visited a new client who needs me to find out why there bills are so high.
At the moment I can only give a quick rundown of the installation as it was just a general chit chat about the issue. I will be going back to do some proper investigation in a week or so.
This is an old manor farm with the main house having been extended along with an attached barn conversion which is their main living space. 3 story's including the loft conversion so quite a considerable space. They have a 3 bed cottage ( Detached )on the land along with stables a plant room and a wooden barn converted for parties in an L shape. So they called me because they are getting extremely high bills. The 2 that I saw was 1 for last 3 months and 1 for the previous 3 months. The latter was for £4100 and the other was £2700. I did get a quick look at a couple others and they were similar costs ranging anywhere in between.
Firstly can anyone say whether this is normal for a house of this size when they have assured me that they don't use the emersion heaters as they have 2 big oil boilers in the plant room.
Wet underfloor in the new half and the barn end and radiators in the old part of the house.
Also my first thoughts are that I need to familiarise myself with the wiring of the entire installation so I can eliminate circuits one by one. Any advice is welcome as always.

 

[telectrix]

you will need to attach an energy monitor for a few weeks.

 

[Pete999]

you will need to attach an energy monitor for a few weeks.

What he said ^^^^^^^^^^^^^^^

 

[westward10]

Smart meter been fitted?

 

[chris day]

Smart meter been fitted?

find out if its single phase, two phase, or single phase.
Rent an an energy consumption monitoring unit which will simple have clip on CTs.

you could have fault current flowing through a high impedance path with would be seen as a large load and not trip any protective devices, its possibly a TT system you have on site

 

[Pete999]

Smart meter been fitted?

Nnever thought of that one.

 

[sparky1508]

Smart meter been fitted?

No smart meter yet but they said one is being fitted soon, but not sure how soon.

 

[sparky1508]

find out if its single phase, two phase, or single phase.
Rent an an energy consumption monitoring unit which will simple have clip on CTs.

you could have fault current flowing through a high impedance path with would be seen as a large load and not trip any protective devices, its possibly a TT system you have on site

It is 3 phase main DB in the plant room.
3 phase DB in main house which had been completely redone around 2008.
Single phase CU in party barn.
Single phase CU in cottage.

Was thinking something similar myself about current flow but not sure where that current would be flowing.

 

[buzzlightyear]

This is an old manor farm with the main house having been extended along with an attached barn conversion which is their main living space. 3 story's including the loft conversion so quite a considerable space. They have a 3 bed cottage ( Detached )on the land along with stables a plant room and a wooden barn converted for parties

what do they except with that to have free electricity.
may be some one leaving a light on to longer!

 

[westward10]

Are they estimated bills.

 

[sparky1508]

Are they estimated bills.

Not sure, will have to ask.
Would that make such a massive difference?

 

[sparky1508]

what do they except with that to have free electricity.
may be some one leaving a light on to longer!

Do you think that £4100 is acceptable for a quarter when they know they don't use a lot of electricity themselves. Clearly they don't want free electricity and I can assure you they quite well off but why would anyone pay for something that they are not using regardless of how much money they have. Really don't see the point in your comment.

 

[sparky1508]

find out if its single phase, two phase, or single phase.
Rent an an energy consumption monitoring unit which will simple have clip on CTs.

Where would be a good place to rent one from.

 

[buzzlightyear]

are producing & they selling bob hope !

 

[buzzlightyear]

Clearly they don't want free electricity and I can assure you they quite well off

may be the electricity company they get
the supply from need to be involved and ask them.

 

[sparky1508]

may be the electricity company they get
the supply from need to be involved and ask them.

Thought about involving DNO but they will say they are only responsible for the installation up to the meter so don't really know what they could do other than charge a fortune to do what I intend to do.

 

[Lucien Nunes]

Let's see what kind of load you need to rack up those bills.
Typical leccy price 12p/kWh
Total consumption over 6 months (4100+2700)/0.12=57MWh
6 months = 24*365/2=4380 hours.
Average continuous load 56666/4380=12.9kW.

Whatever you use electricity for, by the time the energy leaves your house it's almost entirely converted into heat (unless you live in a pumping station or mine headworks). Therefore if this consumption is real, there must be the equivalent of 6 1/2 2-bar fires of heat being pumped into the house all the time. Unless some of the long-hour load is aircon of course. If you were supposing half of the consumption were due to a fault, whatever makes up the resistance of the fault (earth rod, someone suggested) would be getting as hot as two immersion heaters on full whack could make it (i.e. not cycling on their thermostats, elements on full all the time).

It seems unlikely that so much energy could be dissipated unseen in a domestic environment, so either they have a generally high load (e.g. sneaky extra electric heaters and/or aircon and poor thermal insulation, lots of inefficient decorative tungsten lighting on 24/7, all their considerable space in use much of the time) or the readings are out. Unless, of course, someone has set up a hydroponic cultivation department.

 

[buzzlightyear]

someone has set up a hydroponic cultivation department.

note post 14

 

[sparky1508]

note post 14

An initial thought of mine was because the plant room is in an outbuilding it wouldn't be difficult for someone to tap in and leech off it. My clients wouldn't even know as they spend a lot of time away working.

 

[buzzlightyear]

may be you need this guy!

 

[Octopus]

Get the home owner to take weekly readings for a few weeks.

That said £4100 for a quarter is a joke.

 

[sparky1508]

I will be doing as advised earlier and fitting an energy monitor. Might do a week on the main DB and then a week on each sub mains DB. Not even sure if the other 3 subs come from the main DB as the cottage is close to the main house so may be fed from there. Will know more after my initial investigations.

 

[ruston]

are producing & they selling bob hope !

Or someone might be without their knowledge.
Do they have a swimming pool by any chance?

 

[sparky1508]

Or someone might be without their knowledge.
Do they have a swiming pool by any chance?

No swimming pool that I am aware of and I'm pretty sure it would have been spoken about today if they had.

 

[sparky1508]

Or someone might be without their knowledge.
Do they have a swiming pool by any chance?

There is also a couple that live in the cottage.

 

[ruston]

There is also a couple that live in the cottage.

Maybe the place to start then.

 

[sparky1508]

Thinking may get away with a clamp meter as I've just seen the price of these machines. Just check current flows to each DB and see which one has got an unusually high current flow.

 

[buzzlightyear]

now your thinking!

 

[freddo]

We've recently been using Inlec to hire some data loggers, their service is top notch, would highly recommend.

 

[westward10]

Meter readings are rarely incorrect unless smart meters are involved. Even estimated readings are based on past consumption so I would guess somewhere along the line this power is being consumed.

 

[davesparks]

Thinking may get away with a clamp meter as I've just seen the price of these machines. Just check current flows to each DB and see which one has got an unusually high current flow.

That will only tell you the instantaneous current flow, it won't tell you anything about the average demand.

I would say the first thing to do is contact their electricity supplier (the meter operator, not the DNO)
I believe they are required to investigate if there is a query about the bill.

As mentioned above if the bulls are estimate s this may be part of the cause. Have a look at previous bills to see if there is a gradual increase over the years or if this is a sudden jump up.

 

[dmxtothemax]

Leakage in underground cables is not uncommon,
have you tried testing any underground sections
I would do a megger test on any underground sections ?

 

[Leyland30]

The expense of a data logger at this stage seems a little excessive, a basic clap meter will allow you to identify the circuit (s) with high loadings. If you can't identify an issue with this method then a data logger might be considered a robust method of demonstrating a meter malfunction to the DNO.

However, Do DNOs offer meter calibration testing - only charging the customer if no fault is detected.

Let us know how you get on.

 

[Pete999]

I thought I had caught at one stage of my life, lucky it was a false alarm.!!!

 

[GMES]

I bought myself the Fluke 1730 Energy logger and it's already paid for itself at nearly 2k it wasn't a knee jerk purchase but I've had it hired out nearly every week since I bought it so it is now making money every week.
They are well worth the money, simply input the unit price for electricity and it will work out exactly what your installation is costing.
The logging period can be set from 10 minutes to 3 months and at the end you can print off the results or email them direct to your customer, equally you can drag snapshots off of it with a memory stick while it is logging.
We also use it to carry out load tests on machinery, some of our customers like to know what some of their large machines are costing to run for help with working out production costs.

 

[Octopus]

Problem with such vague posts such as these as we are all guessing.

OP - you need to ask the customer to get out ALL their old bills, and

1. look at the amounts due
2. they need to check if they are estimated or proper readings
3. also log the consumption per quarter

- only then can they actually compare apples with apples.

 

[sparky1508]

I will be doing tests on all circuits making the underground ones a priority. I feel with that amount of current flowing it shouldn't be hard to find.

 

[buzzlightyear]

Leakage in underground cables is not uncommon

they need to put a smart meter in for downton abbey !

 

[Lucien Nunes]

with that amount of current flowing it shouldn't be hard to find.

Indeed not. If half the bill is wastage via leakage to earth, the L-E insulation resistance would be 8.2 ohms, so about a ten-millionth of what you might expect on a domestic system. You would want to search for it with a continuity tester, not an insulation tester, as that would just read a string of zeroes - 0.000008 Megohms if it had that many digits. Somehow I doubt this as the cause - the fault would be dissipating the heat of over three 2-bar fires, which I can't imagine XLPE SWA withstanding for over six months. The ground would probably be steaming! Although anything is possible until you get some data.

 

[Midwest]

may be the electricity company they get
the supply from need to be involved and ask them.

Think this is the most sensible suggestion to check first. Why pay hundreds of pounds getting an electrician to check if there is something wrong with the electrical installation, if they've got some dodgy meters or readings.

Get the fuel supplier to verify their meters.