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ASHPs: worth it?
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chamelion
Posts: 483 Forumite


Hi folks,
I've just had solar installed some weeks back and am now looking into whether ASHPs would be a worthwhile investment. I've gone through the faq thread and am even more puzzled given extreme views on either side!
Key facts:
I've been digging around and the furthest i've managed to get is needing a wall mounted inverter ASHP. Not sure of kwh required.
Are these things worth it? This house is naturally unfortunately a bit on the cold side, but we would unlikely be running this ashp around the clock. with electricity as expensive as it is, would this work out any better than what we do for gas now?
for e.g. i'm working at home right now - based on smart meter monitoring i use about 15-20p of gas in the first hour to warm up the study and 4-6p per hour to keep it nice and warm. rest of the house is cold, but i'll probably hit 30p to heat it up and another 10p per hour to keep it toasty.
that's not MUCH but i wouldn't mind investing a bit in a technology if it meant i could keep the house warmer (rather than be confined in a warm room) especially if i'm generating surplus power through solar.
any views much appreciated!
I've just had solar installed some weeks back and am now looking into whether ASHPs would be a worthwhile investment. I've gone through the faq thread and am even more puzzled given extreme views on either side!
Key facts:
- I have solar power
- House is 150 sq metres
- RHI payment estimate for my property is £850 annually if "hot water is provided" (no idea what that means?) - based on calculator at https://renewable-heat-calculator.service.gov.uk
I've been digging around and the furthest i've managed to get is needing a wall mounted inverter ASHP. Not sure of kwh required.
Are these things worth it? This house is naturally unfortunately a bit on the cold side, but we would unlikely be running this ashp around the clock. with electricity as expensive as it is, would this work out any better than what we do for gas now?
for e.g. i'm working at home right now - based on smart meter monitoring i use about 15-20p of gas in the first hour to warm up the study and 4-6p per hour to keep it nice and warm. rest of the house is cold, but i'll probably hit 30p to heat it up and another 10p per hour to keep it toasty.
that's not MUCH but i wouldn't mind investing a bit in a technology if it meant i could keep the house warmer (rather than be confined in a warm room) especially if i'm generating surplus power through solar.
any views much appreciated!
5.41 kWp System, E-W. Installed Nov 2017
Lux + 3 x US2000B + 2 x US3000C battery storage. Installed Mar 2020.
Lux + 3 x US2000B + 2 x US3000C battery storage. Installed Mar 2020.
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Comments
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If you've got mains gas then I wouldn't contemplate a heat pump. You need a proper system design and it's highly unlikely that your existing radiators will be adequate.
You RHI would be based on the amount of heat the unit is forecast to produce (per your EPC) so the comment about hot water relates to heating your hot water tank. It's possible to have an ASHP which just provides heating so your RHI would be less than if it was providing both heating and hot water.
I've got an ASHP because I dont have mains gas and I didn't want oil or LPG and the system was designed from scratch.
I'm also of the opinion that as the unit is working hardest in the winter when the days are short and there's not much sun about then there's not much advantage in having solar power.
Ours is running all day, keeping the house warm and is costing between £3-5 a day depending on how cold it is and whether it's washing day or not.Never under estimate the power of stupid people in large numbers0 -
matelodave wrote: »If you've got mains gas then I wouldn't contemplate a heat pump. You need a proper system design and it's highly unlikely that your existing radiators will be adequate.
You RHI would be based on the amount of heat the unit is forecast to produce (per your EPC) so the comment about hot water relates to heating your hot water tank. It's possible to have an ASHP which just provides heating so your RHI would be less than if it was providing both heating and hot water.
I've got an ASHP because I dont have mains gas and I didn't want oil or LPG and the system was designed from scratch.
I'm also of the opinion that as the unit is working hardest in the winter when the days are short and there's not much sun about then there's not much advantage in having solar power.
Ours is running all day, keeping the house warm and is costing between £3-5 a day depending on how cold it is and whether it's washing day or not.
this really helps, thanks! Didn't think it would be worth it in my case - nice for the comfort but pricier than running my boiler on gas...5.41 kWp System, E-W. Installed Nov 2017
Lux + 3 x US2000B + 2 x US3000C battery storage. Installed Mar 2020.0 -
Would agree that if you have gas, don't contemplate an ASHP.
Loads of posts on MSE on the subject.0
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