Is switching to electric heating a bad idea

Spoonie_Turtle

TroubledTarts said:

QrizB said:

Here are those calculations I promised.

Gas boiler.

• Ofgem national average gas consumption: 11500kWh/yr.
• Capped tariff 6.34p/kWh + 31.65p/day.
• Total annual cost (11500x0.0634 + 365x31.65) = £844.62.

Electric boiler.

• Equivalent electricity demand to match a 90% efficient gas boiler: 11500x0.9 = 10350kWh/yr.
• Capped tariff 24.86p/kWh + zero extra standing charge.
  
• Total annual cost (10350x0.2486) = £2573.01.

Heat pump.

• Equivalent electricity demand at COP of 3 to match a 90% efficient gas boiler: 11500x0.9/3 = 3450kWh/yr.
• Capped tariff 24.86p/kWh + zero extra standing charge.
  
• Total annual cost (3450x0.2486) = £857.67.

So replacing a gas boiler with an electric one, in Ofgem's average UK home, would add an extra £1728.39 a year to your energy bill. Replacing it with a heat pump would only add £13.05.

Your gas figure per kwh should have been 6.34p+10% as a boiler won't be 100% efficient I think I have read it right 

He accounted for that in the electricity calculations, using 90% efficiency to make sure the amounts of energy in kWh are equivalent.

QrizB

Spoonie_Turtle said:

TroubledTarts said:

QrizB said:

Here are those calculations I promised.

Gas boiler.

• Ofgem national average gas consumption: 11500kWh/yr.
• Capped tariff 6.34p/kWh + 31.65p/day.
• Total annual cost (11500x0.0634 + 365x31.65) = £844.62.

Electric boiler.

• Equivalent electricity demand to match a 90% efficient gas boiler: 11500x0.9 = 10350kWh/yr.
• Capped tariff 24.86p/kWh + zero extra standing charge.
  
• Total annual cost (10350x0.2486) = £2573.01.

Heat pump.

• Equivalent electricity demand at COP of 3 to match a 90% efficient gas boiler: 11500x0.9/3 = 3450kWh/yr.
• Capped tariff 24.86p/kWh + zero extra standing charge.
  
• Total annual cost (3450x0.2486) = £857.67.

So replacing a gas boiler with an electric one, in Ofgem's average UK home, would add an extra £1728.39 a year to your energy bill. Replacing it with a heat pump would only add £13.05.

Your gas figure per kwh should have been 6.34p+10% as a boiler won't be 100% efficient I think I have read it right 

He accounted for that in the electricity calculations, using 90% efficiency to make sure the amounts of energy in kWh are equivalent.

Yes, Ofgem's TDCV figure is for the amount of gas used (which is metered) not the useful heat delivered.

Edit:

Two all-electric heating options that I didn't mention are storage heaters or a thermal battery.

Storage heaters will cost you something like £1000 a room and will involve some significant rewiring. A thermal battery (like the Tepeo ZEB) will replace your current boiler and heat your existing radiators but costs about £8k.

Both systems are designed to make use of cheaper off-peak electricity, storing heat until you need it later in the day. Either will still be 50-100% more expensive to run than your current gas boiler.

TroubledTarts

Spoonie_Turtle said:

TroubledTarts said:

QrizB said:

Here are those calculations I promised.

Gas boiler.

• Ofgem national average gas consumption: 11500kWh/yr.
• Capped tariff 6.34p/kWh + 31.65p/day.
• Total annual cost (11500x0.0634 + 365x31.65) = £844.62.

Electric boiler.

• Equivalent electricity demand to match a 90% efficient gas boiler: 11500x0.9 = 10350kWh/yr.
• Capped tariff 24.86p/kWh + zero extra standing charge.
  
• Total annual cost (10350x0.2486) = £2573.01.

Heat pump.

• Equivalent electricity demand at COP of 3 to match a 90% efficient gas boiler: 11500x0.9/3 = 3450kWh/yr.
• Capped tariff 24.86p/kWh + zero extra standing charge.
  
• Total annual cost (3450x0.2486) = £857.67.

So replacing a gas boiler with an electric one, in Ofgem's average UK home, would add an extra £1728.39 a year to your energy bill. Replacing it with a heat pump would only add £13.05.

Your gas figure per kwh should have been 6.34p+10% as a boiler won't be 100% efficient I think I have read it right 

He accounted for that in the electricity calculations, using 90% efficiency to make sure the amounts of energy in kWh are equivalent.

Ah yes I see that now by why the low cop.

Why be accurate with 10% for gas but such a low cop on ASHP where even with our aging heat pump it's 3.6.

Is a cop of 3 the recognized industry mark?

Spoonie_Turtle

TroubledTarts said:

Spoonie_Turtle said:

TroubledTarts said:

QrizB said:

Here are those calculations I promised.

Gas boiler.

• Ofgem national average gas consumption: 11500kWh/yr.
• Capped tariff 6.34p/kWh + 31.65p/day.
• Total annual cost (11500x0.0634 + 365x31.65) = £844.62.

Electric boiler.

• Equivalent electricity demand to match a 90% efficient gas boiler: 11500x0.9 = 10350kWh/yr.
• Capped tariff 24.86p/kWh + zero extra standing charge.
  
• Total annual cost (10350x0.2486) = £2573.01.

Heat pump.

• Equivalent electricity demand at COP of 3 to match a 90% efficient gas boiler: 11500x0.9/3 = 3450kWh/yr.
• Capped tariff 24.86p/kWh + zero extra standing charge.
  
• Total annual cost (3450x0.2486) = £857.67.

So replacing a gas boiler with an electric one, in Ofgem's average UK home, would add an extra £1728.39 a year to your energy bill. Replacing it with a heat pump would only add £13.05.

Your gas figure per kwh should have been 6.34p+10% as a boiler won't be 100% efficient I think I have read it right 

He accounted for that in the electricity calculations, using 90% efficiency to make sure the amounts of energy in kWh are equivalent.

Ah yes I see that now by why the low cop.

Why be accurate with 10% for gas but such a low cop on ASHP where even with our aging heat pump it's 3.6.

Is a cop of 3 the recognized industry mark?

I don't know but a lot of heat pumps are installed in social housing, so the residents haven't had a choice or read up on the intricacies of how to get the best out of them, and chances are the installers aren't experts either.  Our experience was they set it for continuous heat and hot water rather than efficiency, told us to touch nothing except the wall controller, and left us with zero helpful info whatsoever.  If anything goes wrong, we're to call the Housing Association, we weren't even given basic troubleshooting info.

The little I've learned to enable us to get to a COP above 3 (from 2.6) has all been online, and at the prompting of this board because I didn't even know we could change settings to make it more efficient.  And I cannot imagine that our situation is/was in any way unique, if the thousands of social housing heat pump installations tend to be left set for 24/7 heat and hot water rather than any real efficiency considerations and given a similar amount of information, i.e. none useful.

TroubledTarts

QrizB said:

TroubledTarts said:

Ah yes I see that now by why the low cop.
Why be accurate with 10% for gas but such a low cop on ASHP where even with our aging heat pump it's 3.6.
Is a cop of 3 the recognized industry mark?

COPs are an eternal source of debate, but usually on the "heat pumps" subforum or the "green & ethical" board rather than over here! Usually, it's well-intentioned and well-informed prople arguing that a COP of 3 is optimistic and we should use a lower number in these comparisons. It mkes a change to have someone arguing that the illustrative COP should be higher than 3, not lower.

There have been various real-world trials and studies, involving ordinary people rather than heat pump enthusiasts. The three that usually get mentioned are:

• The from 2008-2013. The median COP for ASHPs was 2.45.
• Therom 2017. Performance had improved slightly, with a median COP for ASHPs of 2.65.
• The  from 2021-23. Another slight improvement, with a median COP of 2.80.

You might argue that technology has mocved on from the 2000s and 2010s, but the last of those trials used equipment and installation standards that remain applicable today. As a result, I'm very reluctant to use a COP that's better than 3 when illustrating costs for heat pumps.

It's also apparent from the number of people we get posting on the forums here saying "my brand-new heat pump's expensive to run and I'm still cold" that you're not guaranteed to get decent performance without careful tweaking, even when installed today.

See alsowhere we've been discussing the diminishing returns seen from COP improvements, and what it's worth spending to improve that number.

Of course we generally on heat of problems not the successes that's the nature of forums. Otherwise we would brand everything produced as not up to spec and crap.

Thanks for the links btw but yes we'll out of date and it would be nice for us all to get some up to date figures.

tamste

Hi Shivering
Don't want to know the nature of your disability (that's your business), but with some conditions which are made worse by cold, you cold possibly get a heat pump system and solar panels all fitted for free using ECO4 Flex. There is a section in this scheme which doesn't consider your income level and is based on your health only. This scheme is run through the local authority and ECO4 Flex route 3 and needs an NHS referral:

FLEX Route 3: NHS Referrals

The third route is specifically for households where someone suffers from a severe or long-term health condition that is made worse by living in a cold home. Under this route, the Local Authority must receive a referral from a healthcare professional, such as a GP or NHS Trust, certifying that the household includes someone with one of the following conditions:

• A cardiovascular condition
• A respiratory disease
• Limited mobility
• Immunosuppression

debitcardmayhem

@tamste finally someone has got the thread back on track, well done. Hope @Shivering returns