Smart meter installation gone a bit wrong

Scot_39

If interested in long term energy use tracking work in kWh not just pence and for tracking what devices may be on live watts or kW power not pence.

As although prices fallen from double at peak even for those when govt debt / future taxes were paying c34p electric and 6p gas per kWh for use - the ofge svt cap still c75% above pre crisis lows adjusted for cap tdcv drop.

Old tdcv set caps
Jan21 cap £993,
Jan 22 cap £1212,
Jan 23 £4059 - reduced to £2500 effective by epg - for those eligible by govt debt and taxes paying c34p electric and ?? 6->7p gas ?? 
New tdcv set caps 
Jan 24 £1928,
Jan 25 £1738

Distorts any price based consumption savings / efficiency tracking.  

As you can control choice and use of devices - you have much less control - on the prices paid even if fix or use Octopus trackers they still track longer term trends in fact leading the svt cap down as prices were falling.

So 10kWh per day always shows as 10kWh and not £1.70 one year,  £2.40 one year and £3.40 etc at epg peak.
And a 3kW kettle shows as such rather than 72p example.  So needing to divide by unit rate c24p etc.


As to overnight 

Try an app like brite (or try your suppliers on line portal and look at 1/2 hrly data - they may display the previous days use there)  to help track your overnight cost concerns.

1/2hr on a typical 3kW immersion heater would show a clear  1.5kWh spike.

Or simply switch it off at the isolator switch nearby - and see if it drops by 1.5kWh / c35p if tge 72p now was a 3kW fast boil kettle at c24p/kWh rate.

Bluey87

I’ve just gone down to the cellar and turned the immersion off at the isolator and it immediately dropped, the shower was being used at the time so it correlates. 

I now just need to understand if I need the immersion turned on at all or if I can just keep the hot water running via Hive all the time. 

As it happens the hot water is slow to the taps as it’s a sizeable house and the pump only runs when the hot water is switched on the boiler so it may be a plus. 

My electrician who rewired the house was a bit useless, he drilled through a toilet waste pipe when fitting an outside light, this was the last thing he did, before he smashed a nice pendant in the hallway. I think he’s set the water cylinder to be more dependant on electric than gas which isn’t what I wanted. 

Ildhund

Reed_Richards said:

I read 9841.23.  

I concur, except that if we're being pedantic, I'd say 9841.24. Bluey might have to call that 09841 if the submission needs five digits. 

I find it easier to write down the digits from right to left, so 0.2 + 1 + 40 + 800 + 9000 + 0 = 9841.2. I'm surprised that a meter engineer got this wrong, although they all seem to have variously bad handwriting. I bet the girls' figures are clearer than the boys', though.

Scot_39

250l would take nearly 5 hrs to heat with an immersion from full cold to 60C  - just under 15kWh.

If enabled but at different times to gas - they often will trigger part time - even run in parallel with gas boilers.

Many found there's triggering when started to cut boiler temps or times - changing the balance. 

A coleague found his electric use up 10kWh+ when he thought he could switch his gas for water i summer on only 1hr per day before family showers.  
The immersion saw the temp drop from large demand and het the tank back up.

He soon put the gas back on.

A tank will lose heat even without using hw - its why your tank cabinet or laundry cupboard is permanently warm.

Your gas boiler has maybe 20kW effective peak power at the boiler end - the indirect tank coil heat exchanger not sure - and will drop as tank heats -  and temperature differential drops - the other the electric typically 1 or 2 elements typically 3kW each continuous regardless of water temp until thermostat switches off - 3kW same as a fast boil kettle.


I would expect gas to be carrying the bulk of load.

Your only showing c60p-70p above typical SC by 8am  - just 2-3kWh max.

Take off your 2p an hour low, maybe another 10p for fridge compressor etc over 8 hrs etc.  You wouldn't be covering much more than tank losses (easily 1.5kWh daily for modern 250l) - let alone daily hw use for 2.

Bluey87

Yes it does seem to be carrying the load when we are in the shower, we both enjoy a long hot shower too so I can see why it’s kicking in. 

I’ve turned it off for now so let’s see if that makes a difference today and perhaps the boiler can do the majority of the lifting. My smart meter should kick in with Octopus’ app shortly and I’ll be able to track. 

It’s more about the comfort for me but I also like to be sensible with the pennies, let them look after the pounds and all that jazz, if a tweak saves some energy that’s a good thing for all. 

EDITED TO ADD: can you not just leave hot water enabled all the time (on Hive) and it’ll kick in when it needs to where the immersion did before?

Scot_39

Even although gas a little less efficient - its as little as 7-8p effective / kWh vs 24.5p electric.

That 17p adds up very quickly for things like tank fed showers - when might easily use 1-2kWh per shower.

Sadly my showers electric - so fed from cold not hot - so I heat my tank - about half the size of yours - as well.  Tank off peak - shower also when can - so 18p / kWh not 30p/kWh.

Using its own 9.5kWh element - for 10min - and thats at a pretty feeble flow rate in winter to have it warm let alone hot - is c1.6kWh - c40p at 24.5p SR.

Assuming your shower is tank fed - the immersion could easily trigger and even if gas on - run in parallel - two heaters heating rather than 1.

Same as could happen with 1 radiator, one plug in heater in a room.

Its maybe best to view it as a standby heater - not a daily use one - if have a modern gas boiler.

But in summer - with some old boilers "pilot lights" consuming some estimates say c 1500 kWh on average for UK models - the 4-5+ kWh daily meant it was a different balance - for those using very little water heating. 

Rodders53

What a dipstick of a meter installer.  Hope s/he gets a slapped wrist and retraining.

AFAIK Hive doesn't control electric immersion heaters??  Just gas/kerosene/lpg boilers.  But 30 minutes would be about right for reheating a HW tank, probably, via a gas boiler.

Our unvented HW tank loses around 2 kWh of energy every 24 hours.  It takes around 30 mins to reheat a tank of water used on gas, but 3 hours on electric immersion.

Change the display to show kW/hr being used on left and total kWh used or right,  rather than in money terms.  (The tariff may be incorrect anyway and kWh is more useful in energy consumption usage terms.)
THEN check the numbers broadly agree with your daily kWh readings taken from your analogue meter.

Sign up to use something like Hugo to pull your readings via the DCC to a smartphone and it'll show you more detailed info over time (via 30 minute readings) and no need to actually take the meter readings yourself.

Smart meter IHDs are supposed to be an aid to reducing energy consumption but should not cause alarm like this!

FWIW We use around 3 kWh per day as a base load for the fridge, freezers, things in standby/recording, routers and automated lights etc.,..  When away on holiday.  This time of year we are roughly 8-12 kWh a day depending on how much laundry / cooking etc.,. we do.

I'd be fairly sure you haven't been sitting in the dark with no heating (boilers, controls and pumps run on electricity) and the fridges/freezers off since the installation. Some of those can use a fair bit every day.
What did your meter reads show you consumed each day?

Bluey87

I’ve downloaded Hugo so will have a play with that. 

I’ve also switched off the immersion and increased the hot water production to the below and will see how we go, if we don’t end up running out of HW all will be well in the world. 

EssexHebridean

Interestingly if your immersion has been like that for a while, your smart meter IHD will already have done its job and you should be saving an appreciable amount going forwards! 

Netexporter

It's almost as if getting a smart meter is a smart move, after all.