Cause of massive night time usage?

[Dammo6]

HI Guys,

Hopefully someone here might be able to offer a plausible answer to my question because my electricity provider certainly can't.

I had a smart meter installed last March. Analysis of the data shows that we are using, on average, virtually the same number of units between 00:00 and 08:00 are we are between 16:00 and 24:00. The 8-hour period in between is roughly half.

The meter appears to be fine. I turn off the supply and checked the reading before and after a 40 minute period. It was exactly the same.

The company suggests that it is a faulty appliance but I've tried to explain that there is no appliance that is only on during the night that wouldn't also be on in the evening. So surely all the other appliances that would be on in the evening should see a significantly greater reading in total? I hope this is clear.

Can anyone offer an explanation? Is there something glaring obvious that I'm missing?

Thanks in advance

 

[DefyG]

Honestly have no idea what sort of pump is in it but all I know is that it appears to be costing me a small fortune.

Well no, the pump will be sized for the application so either original design notes or check the pump (assuming it is the original pump).
There may not be an easy solution as it is obviously working (perhaps as it should, unless partial blockage?) and unfortunately all part of the sewage system you have.

 

[Dammo6]

Thanks for the input. Either way I’ll have to get someone to look at it for me.

 

[brianmoooore]

Two types of pump might for found in a sewage system. One is a fairly high powered (HP or so), sewage pump that pushes treated sewage out of the tank where the tank is situated in lower ground than the surrounding area. This type of pump should only run infrequently, and for a short time.
The other type of pump that might be found in a sewage system, mine included, is an air compressor, which is used to agitate and aid with the digestion of the sewage. In the majority of systems, this pump runs continuously (mine seems to run about half of the time, under the control of some expensive electronics). These typically are rated at 100W or less.

 

[Dammo6]

If I was to guess, and it would only be a guess, I have the former.

 

[brianmoooore]

I've had experience of sewage pumps in agricultural applications, and they are very prone to seizing. Possibly this has happened to yours, and any overload protection fitted is inadequate.
Have you looked inside the tank?

 

[Dammo6]

Thanks Brian, even to my ignorant ear, that sounds plausible.

 

[DefyG]

I think if it had seized it would have blown/tripped something or burnt out after all this time. (And you may have noticed by now if pump had stopped or there had been a blockage!!).
As Brian says in #33 the type of sewage system will determine the type and size of pump.
I would also think it the former type and not with a relatively low wattage air pump (although could have both) but usually run on demand (high level) and not just through the night?

 

[Dammo6]

Wish I could answer guys but I genuinely have no idea about this pump other than the process of elimination suggests that it’s the cause of the high overnight usage. Was away for Christmas for a few days and usage was high which suggests that it’s drawing electricity constantly.

 

[DefyG]

Constantly? I'm thinking faulty timer or float switch but if pump had run dry, usually burnt out pump motor !!!?
No, you need to get someone local to look at it, but keeps us updated, its good to know how these things turn out.

 

[Dammo6]

Will do and thanks again for all the input

 

[Zerax]

Is 7kw/h overnight normal usage? I thought I read somewhere that 11kw/h per day was around what the average household uses. Maybe I’m way off.

No such thing as the "average" household... they are all different. Similarly, my water rates bill tells me that the "average" single occupancy house uses 181 litres per day !! Wow... how does anyone use that much ???

 

[Midwest]

The cess pit we have at work, has two large pumps that alternate. They are designed to 'chew up' anything, but get jammed by what people flush down the toilets. Doesn't like dry wipes, underwear, plastic bottles etc. Perhaps your pump has come across these objects?

 

[Dammo6]

I’ll get it checked out. Thanks all.

 

[Dammo6]

Hi All,

An update on the septic tank issue. Hopefully this will make sense.

As I understand it, the outlet pipe broke causing the pump to become permanently submerged and therefore pumping constantly. Hence, the huge (by my standards) electricity bills. It should only come on maybe twice a day for a short period, as per one of the replies above. Thankfully the pump itself isn't burned out and is still working fine. I think he said it's a 1 kw pump (does that sound right?).

 

[brianmoooore]

Without looking back at the previous page and doing some smoke packet calculations, I think it's safe to say you've found the source of your problems.
Any idea how long it's been like this?