Heating method and EPC rating

Cardew

A thought provoking article in the Telegraph today dicusses the effect on the EPC of a Heat Pump or a 'Boiler' (presumably gas/oil/LPG) This subject has been touched upon recently in this forum.

The headline of the article is that on average a Heat Pump costs 27% more to run than a 'boiler'. Whilst there is general agreement that a gas boiler is cheaper to run, that is not the point of this thread. The article states:

'This week it emerged that energy scores for homes are to be overhauled by the Government amid fears that installing a heat pump could cut the value of properties.

Energy Performance Certificates, which grade a home's efficiency, are currently based on what it costs to heat a home rather than the carbon emissions generated. As such, homeowners can risk downgrading their EPC by installing a heat pump.

These certificates are increasingly tied to property prices. Landlords are required to hit a minimum rating under upcoming rules and some mortgage providers take the certificates into account when lending'

So what should be the criteria for a property's EPC?

If  emissions are to be the criteria, it follows that on averge a small property - say a 1 bed flat - will produce less emissions than a 5 bed detached. So shouldn't the former have a lower EPC.

Discuss.

matelodave

Those of us with heatpumps are fully aware of this, but it takes a raft of experts to work it out. My EPC was improved because I got rid of storage heaters but it hadn't occurred to the assessor that heat the hot water from a heatpump was more efficeient and less costly than using an immersion heater., so it got rated as poor.

Stuff that isn't properly though through will always have an unintended consequence. The main benefit of a relaively poor EPC score was that I git more in RHI payments than if it had been done properly

markin

If the running cost are high then was it insulated to good standards? hopefully buyers see the running cost and look elsewhere if they are too high, and not end up starting a thread here!

coffeehound

So they should have named it 'energy running cost certificate' all this time

matelodave

markin said:

If the running cost are high then was it insulated to good standards? hopefully buyers see the running cost and look elsewhere if they are too high, and not end up starting a thread here!

Not sure if you are missing the point of the article - its referring to the anomaly of the Energy Performance Certificate not taking into account the energy efficiency or even reduction of Co2 produced with a heatpump compared with gas. 

Therefore the concept of the present EPC is flawed as it concentrates on cost and not efficiency.

The cost of running a heatpump will always be more than using mains gas whilst there is such a large cost differential between gas and leccy but the cost difference between the two fuels doesn't equate with the efficiency difference between the  the two types of heating systems.

Gas is around 90% efficient, whereas most electric systems are 100% efficient but a heat pump can have an efficiency of 300% or more. In a perverted way, although gas is the least efficient and produces more Co2 it gets a better score on the EPC because its cheaper than leccy.

As the article says, it's more than likely that you could end up with a worse EPC rating by replacing a less efficient  gas boiler with a significantly more efficient heatpump.

[Deleted User]

The database used to populate all EPCs is maintained by BRE. If a particular manufacturer hasn't made its boiler; heat pump or smart heating system etc available to the BRE for testing then the EPC defaults to a base value. For example, I sold a property 4 years ago with Evohome smart heating controls. Evohome wasn't in the BRE database, so the EPC defaulted to 2 heating zones with standard manual TRVs.

EPC assessors just tick a questionnaire on a laptop.

jrawle

Not so much a thought provoking article, rather yet another attempt by the Telegraph to bash heat pumps and net zero targets!

EPCs already give the primary energy usage in kWh/m^2/year. That seems a fair measure. The problem is that if you just go by a headline A-G rating, it's always going to be a blunt instrument. The full certificate already contains information about running cost, efficiency, CO2, etc. You can read the parts that matter to you. (Of course, the noddy way the EPCs are prepared using tick boxes and minimal investigation into how the property is constructed is a different issue.)

Another issue is the public's understanding of the word "efficient". People ask all the time on here questions such as, "Is an electric panel heater efficient?" The correct answer is yes, it's very efficient. However, what they really want to know is whether it's cheap to run.

Cardew

jrawle said:

Not so much a thought provoking article, rather yet another attempt by the Telegraph to bash heat pumps and net zero targets!

EPCs already give the primary energy usage in kWh/m^2/year. That seems a fair measure. The problem is that if you just go by a headline A-G rating, it's always going to be a blunt instrument. The full certificate already contains information about running cost, efficiency, CO2, etc. You can read the parts that matter to you. (Of course, the noddy way the EPCs are prepared using tick boxes and minimal investigation into how the property is constructed is a different issue.)

Another issue is the public's understanding of the word "efficient". People ask all the time on here questions such as, "Is an electric panel heater efficient?" The correct answer is yes, it's very efficient. However, what they really want to know is whether it's cheap to run.

My reading is the article is 'bashing' the EPC system.

Far from 'bashing' heat pumps the article is pointing out the situation where fitting a heat pump - which are clearly more efficient than a boiler in terms of kWh consumed; albeit more expensive to run - can lead to a downgrading of the EPC and hence a reduction in the value of the property in some cases.

This has happens to some posters on this forum. It seems unfair that an investment of £15k to £20k in a property that improves efficiency can devalue that property.

jrawle

I am aware of what the article says; I disabled Javascript especially to read it!

"...installing a heat pump could cut the value of properties"

"...several Cabinet ministers were already concerned about the speed of the transition to net zero"

Then quotes Craig Mackinlay MP, chairman of the self-styled "Net Zero Scrutiny group" as saying heat pumps, "can actually increase energy use," thereby demonstrating that the aforementioned Scrutiny Group haven't a clue what they are talking about. Anyone would think their "scrutiny" is driven by right-wing political beliefs rather than science!

I can see why properties that would be popular with buy-to-let landlords might be devalued if they can no longer legally be rented due to their rating. However, I would hope anyone buying a home actually to live in would consider the content of the whole EPC, not just the headline A-G rating.

EPCs do already have a second rating for "environmental impact" (I just checked a few online). Perhaps the rules should be changed to look at this, rather than the "energy efficiency rating".

markin

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.

Swipe

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.