@derek-m the problem with that is trying to get it assessed in a consistent way? Taking into account numbers, ages of occupants? at home all day? impact of solar gain? some people heat whole house ... others heat one room only to say 20 or 21... etc etc
i've no idea if its possible to have a way of measuring heat loss in some way to get useful info. But again i'm sure there are many issues with trying to do that so it can be measured in all weathers & times of year!
Listed Grade 2 building with large modern extension.
LG Therma V 16kw ASHP
Underfloor heating + Rads
8kw pv solar
3 x 8.2kw GivEnergy batteries
1 x GivEnergy Gen1 hybrid 5.0kw inverter
Manual changeover EPS
MG4 EV
I meant 70 kWh p.a. per sq.m, not £70Posted by: @mike-patrick@derek-m I like that idea as it's one number that everyone can understand. Hides a lot behind it but a useful heuristic.
Last year for mine (total energy use as ASHP not separately metered) was £70 per year per sq.m. Without others to compare I've no idea whether this is good, bad or typical. The only comparison I know of is my aged relative's house (80's built and well insulated). She uses almost 3x my annual kWh (28,000 KWh of gas and electricity). She can afford it but I've told her to use the coal-effect gas fire less and get a new thermostat for the hall as the existing one seems not to work.
Mike
Grant Aerona HPID10 10kWh ASHP
For comperson I used 10000kw 5 people 230m². But it is a newbuild.
16kw Samsung TDM ASHP. 8.4kw PV, power optimizers 20×420watt panels 6kw SolarEdge inverter.
Posted by: @mike-patrickI meant 70 kWh p.a. per sq.m, not £70Posted by: @mike-patrick@derek-m I like that idea as it's one number that everyone can understand. Hides a lot behind it but a useful heuristic.
Last year for mine (total energy use as ASHP not separately metered) was £70 per year per sq.m. Without others to compare I've no idea whether this is good, bad or typical. The only comparison I know of is my aged relative's house (80's built and well insulated). She uses almost 3x my annual kWh (28,000 KWh of gas and electricity). She can afford it but I've told her to use the coal-effect gas fire less and get a new thermostat for the hall as the existing one seems not to work.
Mike
I was thinking more on a daily or even hourly basis, since that may be more effective when adjusting the weather compensation curve.
One possible way to get a feel for actual heat loss, would be to warm your home to 21C, note the outside temperature and time, then switch off your heating system and time how long it takes for the indoor temperature to fall to 20C, noting the final outside temperature.
By doing the above at several different outside temperatures it may provide the sloop of the heat loss.
It may then be possible to check the results against the calculated heat loss for your home.
@andris I used 7,000kw last year. Slightly bigger house 263m2, 4 people (2 young children).
So that's 26.6kw/m2 per annum
@batalto I see, my total of heating use is a bit of a guess as I don't have a meter. I use 10000kw total usage. Heating about 3500kw. Hot water 2500kw and 4000kw is washing drying all other electrical items.
16kw Samsung TDM ASHP. 8.4kw PV, power optimizers 20×420watt panels 6kw SolarEdge inverter.
I used about 6,500kw for power in the house. However a good chunk of that is my abusing the solar in the summer running AC, a pool heater and a hot tub. So not really representative lol
😀 that's awesome!. Hot tub sounds so good😍
I will just get a big paddling pool and fill it up for the kids for free!
Can't wait to abuse the extra power too😍
16kw Samsung TDM ASHP. 8.4kw PV, power optimizers 20×420watt panels 6kw SolarEdge inverter.
More evidence that the EPC regime is not fit for purpose
The over-prediction of energy use by EPCs in Great Britain: A comparison of EPC-modelled and metered primary energy use intensity
Abstract
This analysis compares the difference between the Energy Performance Certificate (EPC)-modelled and smart-meter measured annual energy use on a like-for-like basis in 1,374 gas-heated British households from the Smart Energy Research Lab (SERL) Observatory. EPCs and metered energy use were converted to primary energy use intensity (PEUI) to provide a comparison of the same quantity for the first time.
We show that EPCs predict significantly more energy use than metered in homes in Great Britain. EPC bands A and B show no statistically significant difference, but all other bands show a significant gap which increases as EPC rating worsens. The PEUI gap widens from −26 kWh/yr/m2 (−8%) for band C to −276 kWh/y/m2 (−48%) for bands F and G. Unlike previous research, we show that the difference persists in homes matching the EPC-model assumptions regarding occupancy, thermostat set-point and whole-home heating; suggesting that occupant behaviour is unlikely to fully explain the discrepancy.
EPCs are a core tool in the residential energy sector, and the gap between EPC-modelled and metered energy use could have a significant impact on policy, research, and industry. Future research should investigate disaggregated components of energy use, the underlying thermal model, and assumptions regarding building characteristics.
Currently viewing this topic 1 guest.
- 26 Forums
- 2,123 Topics
- 46.7 K Posts
- 46 Online
- 4,531 Members
Podcast Picks
Latest Posts
-
RE: ASHP heat output monitoring
As you say its poor either way. Can you start a n...
By JamesPa , 4 minutes ago
-
RE: Ecodan - Legionella Operation Time and Target Temperature
Once the white plastic cap is removed, my immersion loo...
By Old_Scientist , 2 hours ago
-
RE: Replacing Refrigerant on Mitsubishi Heat Pump
@dgclimatecontrol I don't know, but they were not happy...
By DavidAlgarve , 2 hours ago
-
RE: Octopus Cosy & Octopus EV + bidirectional smart tariff, together. What, eh?
The current FAQ says it's not compatible with existing ...
By Old_Scientist , 3 hours ago
-
RE: Why do we need pressurised systems?
A good question @toodles. My old open thermal store and...
By AllyFish , 5 hours ago
-
RE: 300 Liter Tank - Do I have to heat it all?
Cross references for @martingale Background discussi...
By Transparent , 19 hours ago
-
RE: Share Your Experiences with Heat Pump Manufacturer Support
@terry1812 Oh Good! Pleased to help if I can! Regards, ...
By Toodles , 1 day ago
-
It's unclear to me how the Smart Control project work b...
By Transparent , 1 day ago
-
RE: Have Consumers Been Lied to About the Efficiency of Heat Pumps Made in China?
@pavel, this isn't about discrediting Chinese products....
By Mars , 1 day ago
-
RE: Solar Power Output – Let’s Compare Generation Figures
We had an excellent four months (11/3 to 15/7) generati...
By JulianC , 4 days ago
-
RE: Is this just haze or something more?
I think the present somewhat cooler hazy days show the ...
By Judith , 4 days ago
-
RE: My misgivings about installing ASHP and solar panels via the ECO4 scheme...
All noted and accepted and as I say I am sorry that you...
By JamesPa , 4 days ago
-
I think it is very much me that is sitting outside the ...
By Grantmethestrength , 4 days ago
-
RE: Who's your electricity provider and what's your tariff?
Aggregators have been recognised for many years, and it...
By Transparent , 5 days ago
-
RE: Help me keep the faith with my air source heat pump installation
Great news I edited my previous post (probably af...
By JamesPa , 5 days ago
-
RE: Double or Triple Glazed Windows?
@toodles Glad to hear things are progressing well for y...
By TRBob , 5 days ago
-
How to waste energy (and time) playing with AI.
A friend of mine who subscribes to an AI service was ex...
By Toodles , 6 days ago
-
RE: Heat Pump Books For Beginners – Bodge Buster & From Zero To Heat Pump Hero
@topher you’re more than welcome to, yes. I’ll send you...
By Mars , 7 days ago