Green Building Bible, Fourth Edition |
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These two books are the perfect starting place to help you get to grips with one of the most vitally important aspects of our society - our homes and living environment. PLEASE NOTE: A download link for Volume 1 will be sent to you by email and Volume 2 will be sent to you by post as a book. |
Vanilla 1.0.3 is a product of Lussumo. More Information: Documentation, Community Support.
Posted By: marsadayIs the Sap system due to change soon ?Theoretically, Yes. SAP 10.2 is supposedly coming in next summer, though not sure if Covid or other factors may cause a delay.
Posted By: Mike1That's still much too high (just found a figure* for 2020 of 0.181 kgCO2/kWh),To be fair, the emissions for heating should be compared using a weighted average for the heating season, not the annual average.
Posted By: Ed DaviesTo be fair, the emissions for heating should be compared using a weighted average for the heating season, not the annual average.
Posted By: bxmanI think you can safely say the EPC is a broken system and no one has an interest in reforming it
Posted By: John WalshMe too, the EPC should be based on a lower intensity for off-peak electric heating such as E7/E10. Dunno how they would deal with Agile, but they should.Posted By: Ed DaviesTo be fair, the emissions for heating should be compared using a weighted average for the heating season, not the annual average.be interested to to see the average E7 period data by month and region. Such data could be part of trying to force upgrades to EPC based on easily available data.
To get back to EPCs - can't see how anyone can defend the current situation. Appalling and it would make a big difference if EPCs were part of driving standards not holding them back.Absolutely, they are having a real world impact on people who want or need to let out their home, sometimes for reasons beyond their control If they can't make the ludicrous EPC hurdle then they can't let their house while they relocate to a new job, or to move in with their partner for example. An elderly couple near us have been asked to move out of their rented home, the landlord needs to sell it , in part because he can't reach the necessary EPC to continue letting it in the long term.
Posted By: Ed DaviesAn interesting point! I just looked up the figures and looks like the result would still be well below 233 gCO2/kWh:Posted By: Mike1That's still much too high (just found a figure* for 2020 of 0.181 kgCO2/kWh),To be fair, the emissions for heating should be compared using a weighted average for the heating season, not the annual average.
Posted By: WillInAberdeenHi Mike, SAP 10.2 is available on the BRE website. It uses a headline figure of 136 gCO2/kWh for all electricity, apparently an average number looking ahead only to 2024.
Posted By: WillInAberdeenWith a smart meter (which we hear elsewhere are replacing the old dual-rate meters for new E7 installations) you can change tariff/supplier easily. What stops someone being on E7 on the day the assessor visits, taking credit for the low prices on their EPC, and switching to a different tariff the next day?
Posted By: WillInAberdeenMaybe someone would rather be on an Agile tariff? Or an EV tariff?
Posted By: WillInAberdeenAs a first step they are going to reform the EPC system, consultation here (non-Scots also welcome to comment!)
https://www.gov.scot/publications/domestic-epc-reform-consultation/documents/
Posted By: WillInAberdeenBut the current EPC quotes an 'Energy Efficiency Rating' with underlying units of m².a/£ ..... not exactly SI!
TBF the Scottish gov propose to reframe that as a Cost Rating in £/a, retain a Carbon Rating in kgCO2/m2/a and add an Energy Use Rating in kWh/m²/a. (Or possibly the inverse of those units, high ratings for low usage).
On even closer examination, the different carbon figures per month and per tariff are not actually very much different from each other. Maybe this is too much detail.
Posted By: WillInAberdeenthe Scottish gov propose to reframe that as a Cost Rating in £/a, retain a Carbon Rating in kgCO2/m2/a and add an Energy Use Rating in kWh/m²/a.
Posted By: Mike1the new French EPC is based on thresholds for kWh/m2/year & CO2/m2/year
Posted By: Mike1FWIW, the new French EPC is based on thresholds for kWh/m2/year & CO2/m2/year - you have to pass both thresholds to reach a particular grade:
A = <70 kWh/m²/year + < 6 kg CO2/m²/year
B = 70 to 110 kWh/m²/year + 6 to 11 kg CO2/m²/year
C = 110 to 180 kWh/m²/year + 11 to 30 kg CO2/m²/year
D = 180 to 250 kWh/m²/year + 30 to 50 kg CO2/m²/year
E = 250 to 330 kWh/m²/year + 50 to 70 kg CO2/m²/year
F = 330 to 420 kWh/m²/year + 70 to 100 kg CO2/m²/year
G = >240 kWh/m²/year + >100 kg CO2/m²/year
Seems logical to me.
Posted By: Peter_in_Hungaryexcept if the government (or others) fail to get the grid co2/kWh down then your EPC rating gets screwed
Posted By: djhJust to check I've understood correctly - nothing about cost at all, no € signs anywhere?Definitely no €s involved in calculating the rating!
Posted By: djhIs the kWh/m²/year figure Renewable Primary Energy Demand (PER, according to PHI method) or something different?It's the consumation of primary energy used by heating, cooling, hot water, lighting & associated equipment (but pretty sure it doesn't include household appliances).