reduce energy on standby

UKworkshop.co.uk

Help Support UKworkshop.co.uk:

Spectric

Established Member
Joined
19 Feb 2015
Messages
3,828
Reaction score
2,014
Location
North Cumbria
which is then split various ways
I can see you must have a large heat pump to require three phase, is it a 22Kw one? To me it seems we are looking for the holy grail, wanting to extract more energy from a system than is put in which seems to defy physics, many may work in ideal laboratory situations but you here so many people who don't get back what they expect all year round. Be interesting to see your figures when the system is fully instrumented and see how close to three times more output than input you can get.
 

nickds1

Established Member
Joined
25 Jul 2012
Messages
271
Reaction score
254
Location
Somewhere in Kent
I can see you must have a large heat pump to require three phase, is it a 22Kw one? To me it seems we are looking for the holy grail, wanting to extract more energy from a system than is put in which seems to defy physics, many may work in ideal laboratory situations but you here so many people who don't get back what they expect all year round. Be interesting to see your figures when the system is fully instrumented and see how close to three times more output than input you can get.
It doesn't REQUIRE 3-phase, we just happened to have it and 3-phase GS heat pumps are just that little bit more efficient that single phase, so incremental gains. It all counts.

We recently had a full service and firmware upgrade etc. The actual CoP was measured at that time (needs a fair bit of kit) and back in March when it was cold, we had a CoP of 3.9. Obviously that varies with environmental conditions.
 

John Brown

Social media influenza
Joined
25 Sep 2008
Messages
2,510
Reaction score
525
Location
Stinchcombe, Gloucestershire
If you want to get a better / deeper grasp of Ac electrical theory then you need the book "AC CIRCUIT ANALYSIS" by Noble Lockhart & Ora Rice. It is very good even though published in the seventies and some chapters are outdated it got me through college. The theory remains the same, J notation and network theorems have not changed and Kirchoffs loop equations can be invaluable. Back this reading up with "Electrical fundamentals" by Robert Shrader and you get more info on AC circuits as well as an intro to magnetics, a subject that is really interesting and fundamental to modern industry and technology. If you like simplicity then avoid Ac and just stick with Dc!
I'll stick with my vintage copy of "The boy electrician" by Alfred Powell Morgan. It's served me well these past 60 years.
 

fred55

Established Member
Joined
21 Jul 2013
Messages
189
Reaction score
19
Location
pontefract
My head really hurts now - having flash back from too many years ago - multi cage electric motors; 3phase; single phase; root;3 V I cos Q; Kva n Kvar ; power factor correction; Flemings LH rule for motors (or was it RH); flux density F=ILB; step up n step down; Eddy currents; not forgetting fault/breakers calcs from home to power station; good old pit tech ! that's blown some cobwebs off time for a beer.
 

ian33a

Established Member
Joined
18 Mar 2021
Messages
235
Reaction score
257
Location
the centre of Devon
My head really hurts now - having flash back from too many years ago - multi cage electric motors; 3phase; single phase; root;3 V I cos Q; Kva n Kvar ; power factor correction; Flemings LH rule for motors (or was it RH); flux density F=ILB; step up n step down; Eddy currents; not forgetting fault/breakers calcs from home to power station; good old pit tech ! that's blown some cobwebs off time for a beer.

Same for me. Did all of that stuff during my degree and a load more too. Then I went off and spent most of my life in high speed electronic test. Fast fourier transforms, ua, uv, ns, effective bits and a host of other terms filled my brain instead. I struggle to remember much of the above as my little brain would explode trying to retain all of it.
 

NewbieRaf

Established Member
Joined
4 Jun 2019
Messages
199
Reaction score
44
@nickds1 thank you for that. Re the emporia system, what if your like me just not comfortable dealing with sparky stuff aside from wiring a uk plug, can you not just clamp select appliances or the flex from your meter? And that feeds wirelessly to their hub then to the cloud?

thanks
 

ian33a

Established Member
Joined
18 Mar 2021
Messages
235
Reaction score
257
Location
the centre of Devon
@nickds1 thank you for that. Re the emporia system, what if your like me just not comfortable dealing with sparky stuff aside from wiring a uk plug, can you not just clamp select appliances or the flex from your meter? And that feeds wirelessly to their hub then to the cloud?

thanks

I doubt you can connect to appliances around the wire from the mains socket to the appliance. Current clamps need to connect around a single wire, typically the live wire. If you connect around a normal electrical cable which contains a live, neutral and an earth, they don't work. They need to connect to the live tails near the distribution board.
 

nickds1

Established Member
Joined
25 Jul 2012
Messages
271
Reaction score
254
Location
Somewhere in Kent
@nickds1 thank you for that. Re the emporia system, what if your like me just not comfortable dealing with sparky stuff aside from wiring a uk plug, can you not just clamp select appliances or the flex from your meter? And that feeds wirelessly to their hub then to the cloud?

thanks
Regrettably that won't work. The clamps (current transformers or CTs) measure current flowing in a single direction. If you clamp the mains lead to an appliance then you'll be measuring the current in the live wire minus the current in the neutral (as it's flowing in the opposite direction), so the net result should be zero.

The CTs really need to be in the consumer unit clamped on the live cables downstream from the breakers. Plus, the actual monitoring unit (the Vue2) needs to be connected directly to at least one of the breakers and the neutral bus in the CU to power itself and to monitor voltage. Emporia recommend getting a qualified electrician to do the work.

Note that this system originated in the USA where their domestic consumer units (CUs) are more like our light industrial ones, i.e. they have much more space inside than our CUs, so I really wouldn't do this yourself unless you are very happy (and safe) working inside a crowded CU.
 
Last edited:

woodieallen

Established Member
Joined
29 Mar 2021
Messages
292
Reaction score
127
Location
UK
......working inside a crowded CU.


The Emporias system comes with two sizes of clamp. A very large one meant to go over the main tails feeding the consumer unit. As Nick has already said, our consumer units are very tight for space. However, all is not lost.

You get a load of smaller ones and these are much easier to squeeze in. If you have a 'normal' house supply ...ie not 3-phase, solar generation etc then do what I do. I clamp two small ones over the feeds from the two RCDs (split load) and Emporia does the maths for me and adds the two together.
 

nickds1

Established Member
Joined
25 Jul 2012
Messages
271
Reaction score
254
Location
Somewhere in Kent
The Emporias system comes with two sizes of clamp. A very large one meant to go over the main tails feeding the consumer unit. As
Actually there are at least three sizes. A large 200A one for your utility feed, a standard 50A one for the circuits to be monitored, and a larger "wide mouthed" 50A one if you want to monitor tails in a meter cupboard (which I do).

So I'm using all three types - the Vue2 has a maximum of 16 x 50A circuits it'll monitor simultaneously on top of your single or three phase utility supply. I have 3 X 200A CTs for the utility, 6 of the wide mouthed 50A CTs monitoring how the three phase is split out, leaving me 10 free connections for monitoring my CU.

The 50A CTs have a 1mtr cable terminating in a standard 2.5mm mono jack. Emporia tell me that you can extend this to a maximum of 8mtrs/25ft with standard mono 2.5mm extension cables, so I have run a few of these through the wall of my meter cupboard to the CU.
 

woodieallen

Established Member
Joined
29 Mar 2021
Messages
292
Reaction score
127
Location
UK
You have a very complex system. Do you not think that all these complex details might not put off some people from what can be used as a very simple but effective system ?
 
Last edited:

nickds1

Established Member
Joined
25 Jul 2012
Messages
271
Reaction score
254
Location
Somewhere in Kent
You have a very complex system. Do you not think that all these complex details might not put off some people from what can be used as a very simple but effective system ?
No.

Everything I said about UK consumer units is valid - if you're not confident then get a qualified professional to do the work.

If you do know a bit, then you'll see that what I've done is actually nothing very complex or special - a bit left-field, but no more than that.
 

woodieallen

Established Member
Joined
29 Mar 2021
Messages
292
Reaction score
127
Location
UK
Right. No need to be so patronising and arrogant.

I'm out of this thread. If anyone wants further discussions regarding using the Emporia for Normal People then they are very welcome to PM me.
 

nickds1

Established Member
Joined
25 Jul 2012
Messages
271
Reaction score
254
Location
Somewhere in Kent
Right. No need to be so patronising and arrogant.

I'm out of this thread. If anyone wants further discussions regarding using the Emporia for Normal People then they are very welcome to PM me.
I apologize if it came over that way - that certainly wasn't my intention. You asked me a direct question, which in itself could be taken various ways (if I was that thin skinned); I answered it. By "you" in my reply I'm not referring to you personally, but to anyone reading the post - a figure of speech, no more.

What I'm doing is certainly not complex and just highlights the flexibility of the system.

I do however feel that working in a UK domestic CU is not for folk who aren't confident in that.

Further, as you will know, the Vue2 is designed really to be inside the CU with a punch-out for the aerial. - 7/8" - not a UK standard size.

If not installed that way you need a method to safely get the CT tails out of the CU preferably without having to leave the cover off.

If you do leave the cover off, then there are a bunch of H&S issues plus the fire rating of the CU is void.

Finally, if there is a subsequent insurance claim (fire, injury etc ), your domestic insurance could be invalidated.

I'm not intending to be "patronising or arrogant" - the Emporia Vue2 is great and can be used in lots of different configurations, some extremely simple and straightforward, but messing in domestic CUs is something to be done with caution. Just because you can do something doesn't mean you should - there can be serious consequences.
 
Last edited:

Just4Fun

Established Member
Joined
21 Sep 2017
Messages
967
Reaction score
337
Location
Finland
I can see you must have a large heat pump to require three phase, is it a 22Kw one? To me it seems we are looking for the holy grail, wanting to extract more energy from a system than is put in which seems to defy physics, many may work in ideal laboratory situations but you here so many people who don't get back what they expect all year round. Be interesting to see your figures when the system is fully instrumented and see how close to three times more output than input you can get.
We also have a phase supply for our (17 Kw) GSHP. The specifications claim:

°C Kw
In Out In Out COP
------------ ------------- ---
0 35 3.84 16.8 4.4
0 45 4.8 15.7 3.3
0 50 4.9 16.2 3.3


I have no way of knowing whether we achieve that in reality. Nor do I care. For most of the heating season our incoming brine temperature is below 0 degrees so that would throw the figures off, but even ignoring that the COP is not the measure I am interested in. Rather, the cost of running the systemis what I care about.
Before fitting the heat pump we heated the house with oil and used electricity for everything else. The heat pump replaced the oil burner and is purely used for heating the house. (Not for hot water, or anything else). For the first winter with the heat pump our electricity bill, for the GSHP, cooking, lighting hot water, everything, was about 15% lower than the oil had been just for space heating over the previous winter. Hence we saved money, which was the objective. We installed the GSHP in 2007 so I imagine the savings are greater now, given the way oil prices have changed.

Regards trying to get more energy out of the system than we put in, that is indeed the goal. The important thing is to get more out that we put in; we cannot get more out than goes in in total. It is just that the energy we put into the system is not the only going into the system. The energy we put into the system is used to extract energy from the ground, and no laws of physics are challenged.
 

nickds1

Established Member
Joined
25 Jul 2012
Messages
271
Reaction score
254
Location
Somewhere in Kent
We also have a phase supply for our (17 Kw) GSHP. The specifications claim:

°C Kw
In Out In Out COP
------------ ------------- ---
0 35 3.84 16.8 4.4
0 45 4.8 15.7 3.3
0 50 4.9 16.2 3.3


I have no way of knowing whether we achieve that in reality. Nor do I care. For most of the heating season our incoming brine temperature is below 0 degrees so that would throw the figures off, but even ignoring that the COP is not the measure I am interested in. Rather, the cost of running the systemis what I care about.
Before fitting the heat pump we heated the house with oil and used electricity for everything else. The heat pump replaced the oil burner and is purely used for heating the house. (Not for hot water, or anything else). For the first winter with the heat pump our electricity bill, for the GSHP, cooking, lighting hot water, everything, was about 15% lower than the oil had been just for space heating over the previous winter. Hence we saved money, which was the objective. We installed the GSHP in 2007 so I imagine the savings are greater now, given the way oil prices have changed.

Regards trying to get more energy out of the system than we put in, that is indeed the goal. The important thing is to get more out that we put in; we cannot get more out than goes in in total. It is just that the energy we put into the system is not the only going into the system. The energy we put into the system is used to extract energy from the ground, and no laws of physics are challenged.
Exactly. The "First Law of Thermodynamics" is upheld - energy cannot be created or destroyed.

With a GSHP, the sun heats the ground. Electricity is used to drive the GSHP compressor and circulation pumps; the electrical energy input plus the thermal energy extracted from the ground equals the heat provided to the property (minus some losses in the system). A CoP of 1 means that for each Watt of electrical energy in you get 1 Watt of heat out - that's basically what an electric bar fire does.

With a GSHP, depending on environmental conditions, you typically get a CoP of between 3 in the winter and 4 in the summer. If the winter is very cold the CoP can drop below 3 and a modern well maintained GSHP can have a summer CoP of above 4. There are now cunning systems that can increase summer CoP to around 8 and in winter to around 5.5.
 

nickds1

Established Member
Joined
25 Jul 2012
Messages
271
Reaction score
254
Location
Somewhere in Kent
What you need is artificial ground that has been engineered to absorb the most energy from the sun, next best would be to dye the grass black!
Joking aside, there is now a a technique called "inter-seasonal heat transfer" (IHT) for use with GSHPs that warms up the ground even more during the summer so it can be released over winter and cools it over winter for use during the summer - because of the huge storage capacity of the ground, this can double CoP values. I really don't know a lot about this as it's pretty new and may not even be applicable to domestic use. Lots of info on the web about it though, e.g. IHT | Interseasonal Heat Transfer™ | Seasonal Heat Storage | GSHC | Renewable Heat & Renewable Cooling from ThermalBanks | Efficient Renewable Energy | Hybrid Renewable Energy Systems and Thermal Banks store solar heat between seasons | Seasonal Heat Storage | ThermalBanks save carbon emissions | Thermal Energy Storage using Interseasonal Heat Stores | Underground Thermal Energy Storage UTES | Reusable Heat
 

Latest posts

Top