COP reading?

Does anyone know if it's possible to find my COP reading somewhere on the portal or App?

Chrissy
You dont say what kit you have
CoP for what?
I dont think the GiVEnergy portal has any integration with a heat pump ( which would be the most normal thing a CoP is used on)

CoP - Coefficient of Performance. Usually related to Heat Pumps in a domestic environment. The portal does not know about your heat pump - other than it's inclusion in your overall load. Depending on your heap pump you may have access to another app or monitoring device which could give you your CoP. For example, Vailant have a comprehensive monitoring app and portal which gives you tons of control and stats, including CoP under various conditions.

SteveCook Thanks for your reply - and I now realise that you are right... COP is about our heat pump efficiency - not about our battery and solar! So not appriate to ask here. thx

Chrissy
CoP for a heat pumps will vary continuously throughout the day/month/year dependent on the conditions of either "end" of the system. Presumably an air source heat pump. AHSP
One end will be outside air temperature, the other end heating system water.
Best figures to see how your system is performing will need to be taken over a year or number of years (more accuracy as yearly conditions vary)
Think of CoP as (What Get Out divided by What You Put In) over whatever period and conditions you are interested in. This is why seasonal CoP is typically used as it reflects best and worst scenarios,
For an ASHP,
What You Put In is the electrical energy to the motor (compressor), can be measured by electrical consumption meter
What You Get Out is the amount of heat that goes into the water. This is (Tout-Tin) * Cp * M.
Cp=specific heat capacity of water. M=flowrate of water. Tin Tout = temperature of the water in and out of the heat pump. This can be metered.
You would need to both the electric consumption and the water energy over time and then do the division maths.
Maybe Vailant have built the meters into their kit and the calculations into their app,
Be carful of instant snapshots. I can get 50mpg in my car when pootling at 30mph and the next second it will drop to 5mph when accelerating, but overall my car reads about 32mpg. The longer I leave it, the greater the accuracy of the overall mpg reflects all driving conditions encountered

SteveCook Dear Steve, Thanks for the information and your advice, chris

Chrissy My heat pump (LG Therma V) doesn't display CoP.

If your heat pump displays CoP then great. There are third party systems that can measure CoP for you such as Open Energy Monitor https://openenergymonitor.org/ but these are not cheap and have to be plumbed in.

I have spent ages trying to work out what the CoP might be based upon trying to measure flow and return temperatures measured externally from the pipes and then deriving a CoP using the formulae as mentioned by Steve.
Load of effort and data but never got anything meaningful from it.

Instead I'd suggest you focus on ensuring your heat pump is running as efficiently as possible. By turning on weather compensation, adjusting the hot water and flow temperatures to be as low as possible, turning off the immersion heater and just using the heat pump for hot water, and running the heat pump low and slow with an overnight setback temperature, I have reduced my heat pump consumption by 40% over the years:

Ultimately the least heat you can put into the house the most efficient and highest CoP your heat pump will achieve

geoffreycoan Thanks for your helpful tips - after more than year with a heat pump we are slowly starting to get the hang of some of this... been testing out the Havenwise optimising App, and I like the way if show COP info, but on a month the trial and may decide not to keep using it.. our COP was better before we signed up! was just wondering how else we could get that info if we don't stay with them. thanks for your tips, Chris

Chrissy The CoP varies a lot with outside temperature so personally I wouldn’t worry too much about chasing it. And anyway CoP is a bit of a meaningless number, what is more important is how much electricity you used and how much you paid for it.

Very simply, the lower the temperature you can run your heat pump, the lower your electricity consumption will be because CoP decreases and thus electricity usage increases when flow temperature increases.

You want to get your heat pump to the point where it is trickling into the house just what energy is being lost out of the house. Hence the ‘low and slow’. If you run it like a conventional gas/oil boiler then the heat pump will have to work very hard to put back all the lost heat into the home from when the house cooled down, and a heat pump running hard consumes more electricity.

You can see it in my figures, the first couple of years I was running mine a bit like a conventional boiler, I did have it on longer as I recognised that the heat pump took longer to heat the house, but I let the house cool down too much overnight and then that heat has to be put back.
I now heat the house to 19 degrees during the day and a setback of 17 degrees overnight and the house is comfortably warm all the time. When its below freezing my electricity consumption goes up significantly as the heat pump is running hard, but this doesn’t happen that often.

I also schedule my heating times and hot water such that I can take advantage of the cheap rate Cosy periods, with most of my electricity being supplied from the battery at what was the Cosy cheap rate.

geoffreycoan
Be careful with hot water temperatures. How water that comes out of the tap, not going round in the radiators.
The lower temperature you generate/store hot water, the better CoP you will get. You really want the maximum hot water (coming out of a tap) less than 50C, but you need to pasteurize the water regularly to prevent any bacterial buildup. I believe some heat pumps (sorry dont have a heat pump) have an auto pasteurization cycle . Try to store hot water around 50C but run it up to 65C once a week. Yo may need to store water hotter if yo like deep baths and dont want to run out, but CoP will suffer

Our heat pump shows 4.4 for last year. Set on 19c all the time which in reality means the house is 21c with a half degree variance. All on IOG with dhw heating during the cheap period. I just added up our bills for last year. Came to £217. Includes 9k miles on the Tesla with no other fuel bills. I’m happy.

SteveCook You really want the maximum hot water (coming out of a tap) less than 50C, but you need to pasteurize the water regularly to prevent any bacterial buildup. I believe some heat pumps (sorry dont have a heat pump) have an auto pasteurization cycle . Try to store hot water around 50C but run it up to 65C once a week. Yo may need to store water hotter if yo like deep baths and dont want to run out, but CoP will suffer

You are correct you don’t want the domestic hot water coming out of the taps at too high a temperature, it wastes energy heating it up if you are only going to then add cold water to cool it down again. Plus at too high a temperature there is the risk of scalding.

There is a lot written about anti-legionella cycles and whether you need them or not.

There’s a good article and video produced by heat geek https://heatgeek.com/articles/articles-home?p=hot-water-temperature-scalding-and-legionella and recently Jonathan Tracey on his youtube channel ran an experiment to see if there was legionella present in his shower head when he didn’t run the anti-legionella cycle.

The ‘you need to pasteurise the water regularly to prevent bacterial buildup’ is a very simplistic blanket statement. Watch the video, read the article, and make your own mind up.

Personally I set my hot water to 44 degrees and have turned off the weekly anti-legionella cycle, but make your own mind up after researching.

Regardless of whether you run an anti-legionella cycle or not, at least in my heat pump there is configurable options as to how the hot water is heated. By default mine was set to do the first part of the hot water heating with the heat pump, but then do the last 5-10 degrees with the immersion heater. This will give quicker hot water heating but be less efficient and use more electricity as the immersion is at best 100% efficient whereas the heat pump is typically around 250% when heating to domestic hot water temperatures. I changed my settings so the hot water is entirely heated by the heat pump, so its slower to heat, but in practice it takes typically half an hour, maybe up to an hour to reheat the tank which is fine.
I also only heat the hot water once a day in the afternoon in the Cosy cheap period or when hopefully there’s some solar generation. The rest of the time the hot water doesn’t get heated even if the tank temperature drops.

This works for us, but different people’s pattern of hot water usage may mean its not suitable for them.

geoffreycoan it wastes energy heating it up if you are only going to then add cold water to cool it down again.

I keep hearing this. But it goes give you a larger volume of water at the desired temperature.

Dear All - maybe what I am about to post is better under a separate heading for "Heat Pumps"...however, sometime ago I came across the following: https://community.openenergymonitor.org/
I have HY Gen 3 inverter and three 5.2kWh batteries.. I read from the community about weather compensation - which allows the user to adjust the settings to ensure the ASHP uses the least amount of energy according to the outside weather conditions. I have LG Therma V 7kW heat pump for our bungalow (fitted before our solar set up). This community site has various downloads including how to set up several makes of heat pump. I adjusted mine and now it maximises COP and together with COSY for winter months (thanks to this GivEnergy community group (:-)) and Flux in the rest of the year my bills are much reduced. I suggest members with ASHP review this site (and Garydoessolar) to get as much help and advice as required. Andy

AndyZ900rs I'd have thought that installer really ought to set up weather compensation, though they can only make a initial guess at the ideal settings - it does take time to tweak it to closely match the house characteristics.

He put in basic information but I had to monitor and activate it and modify with how we used energy in the house...plus the solar setup altered how we used the system - thanks

A wise man(not me) once said:
COP is vanity
SCOP is sanity
COST is King!

DD I'd have thought that installer really ought to set up weather compensation

You might hope for that. My experience is quite the opposite, the installer set the system up at a fixed temperature, in my case 52 degrees C. First night we hardly slept because it was too hot.

It was only through internet articles did I find how to set weather comp up on mine. It took me ages to discover that there was weather compensation for my ASHP (its confusingly called AI mode), and then even longer to find out how to change it. Its in the installer menu which is both hidden and requires a PIN number!
And even then, it wasn't obvious how to set it up.

My heat pump broke and was repaired a couple of weeks ago; talking to the engineer who fixed it he was really pleased to see that I had weather compensation turned on and I took an interest in my system. He said all too many of the old systems he services for the company are setup without weather compensation, most likely because the engineers of 4 years ago didn't understand it and/or didn't want callbacks because the house was too cold. Setting a fixed high flow temperature ensures the house is warm enough, and the electricity bill, well that's the customer problem ....

Geoffrey - excellent response - this has been my experience as well. The openenergy site gave me so much ..including a pdf how (like you I have LG and weather compensation is called AI) to adjust it to meet my/our needs.

geoffreycoan
Geoffrey please don't get me on the title of an installer/plumber/man with bag of tools etc as an "Engineer"
I spent 2 years doing A levels, 4 years doing a degree and a further 4 years of structured working before I could even apply to be called a Chartered Engineer.
No offence to the guy who fixed your system.

SteveCook Fair comment. I'll refer to him as spanner-man going forward 😜

I worked in IT as a Consultant. Some of my colleagues worked on NHS projects. They got a lot of respect when they introduced themselves as Consultants...

geoffreycoan
Thanks. The man who services my car is a mechanic, not an engineer. Very good mechanic ,knows how to use the tools, knows how to fix things and is very skilled, but probably never trained in car component design (vehicle engineering).
The various "engineers" who came to my house to fit smart meters over a number of years seemed to know very little about networks, communications, etc. They just knew how to pull a fuse and undo/connect cables

Our fitter/plumber/etc didn’t claim he was an engineer (the v.old joke where I was said “yesterday I couldn’t spell engineer- today I are one”) but he did set weather compensation up and I only had to tweak it a bit- pretty easy on Viessman app.