Heating method and EPC rating

matelodave

Swipe said:

markin said:

Is the any recent surveys on if home buyers even read the EPC? I think the last one i read about it was very low, we certainly seem to get a lot of people here that just didnt consider it when buying or renting.

I really didn't care about EPC when I bought my house and I think I upset the EPC guy when I sold mine when asked him if anyone really paid any attention to them. He got very defensive indeed.

Being a bit of a cynic I always though that the EPC was a job creation scheme for Energy Surveyors and trainers with the underlying sinister intention of eventually taxing properties based on their EPC rating (I still think the latter is true and will eventually be introduced)

Strummer22

I just had my EPC updated to claim RHI (just in time!). The change from oil boiler to ground source heat pump reduces the EPC rating - although this is offset by the loft insulation we installed in order to be able to claim RHI payments. The rating went from 39 to 40

The oil boiler was rated 'average' and the GSHP is rated 'poor'. Even though I've read up a bit on this, it's not entirely clear why this is.

The space heating demand is listed as 27,605 kWh and DHW as 2,708 kWh annually for a total of 30,313 kWh. If I understand correctly, this is what the EPC assessor has calculated the thermal output of the GSHP to be. Given the system's SPF of 3.54, this would use 8,563 kWh of electricity annually. However, the primary energy use is 291 kWh/m2 and the floor area 195m2, so I would think the total primary energy use is 56,745 kWh (just multiplied use by floor area - is that the correct approach?). Apparently this is supposed to take into account the efficiency of the heating system, which is 354%. Can anyone help me understand what's going on the underlying calculations? Clearly the primary energy use isn't the total electricity used by the property as that would cost over £10k per year on our current tariff, let alone the higher one that's about to come in!

Reed_Richards

There is some good news here for anyone heating with electricity: https://www.placenorthwest.co.uk/insight/carbon-factors-good-news-for-your-epc-rating/

But I don't know if the change would take into account the fact that heat pumps give more kW of heat than the electricity they consume.

Strummer22

Reed_Richards said:

There is some good news here for anyone heating with electricity: https://www.placenorthwest.co.uk/insight/carbon-factors-good-news-for-your-epc-rating/

But I don't know if the change would take into account the fact that heat pumps give more kW of heat than the electricity they consume.

Interesting read, thanks. That mentions non-domestic property, but what about domestic? Also, the article isn't explicit but implies that this will be applied to all existing EPCs, so a new EPC isn't needed in order to see the new rating. Do you know if that's correct?

I work in a sector related to grid carbon intensity and was surprised to see a factor of over 0.5 kg CO2/kWh being applied for EPC calculations. That's way too high!