Octopus Heat Pumps

mickyduck55

2nd_time_buyer said:

In our case, I found the spec sheets of the current column radiators so it should have been quite accurate. 

Interestingly the required heat output for the house was around 8-9kw. Which is somewhat lower than I might have expected. But it ties in with my gut feeling that two air to air heat pumps could be sufficient.

I installed 2 A2A (split system) one in my living room and one in my bedroom initially for the cooling in summer when I have excess solar.  I have found them to be excellent for heating in winter  Instant heat and 20 x 18 foot room heats up much quicker than with the GCH or my real flame gas fire.  

Bianchiintenso

Our 10mm microbore works absolutely fine with ashp, as does the 2 houses we visited before deciding, installers will however make you sign a disclaimer to cover their backs

thevilla

Reed_Richards said:

Heat Geek make money by training installers...  and they'll have to charge you a bit more to pay back the cost of their Heat Geek training.   

To be fair, if an installer is worth having they will be paying for training whether outsourced or in house.  Heat Geeks are just being up front about how they operate.  I've no experience of their work but that doesn't seem a sensible reason to rule them out.

Reed_Richards

thevilla said:

To be fair, if an installer is worth having they will be paying for training whether outsourced or in house.  Heat Geeks are just being up front about how they operate.  I've no experience of their work but that doesn't seem a sensible reason to rule them out.

An installer should have paid for their necessary MCS training and accreditation.  The Heat Geeks training would be a voluntary add-on.  I don't have anything against Heat Geeks trained installers and certainly didn't intend to suggest anyone should "rule them out".  It's just that there is quite a limited supply of them, probably too limited to want to confine yourself to seeking quotes from them alone. 

JoniFry89

I read that there is a lack of take-up of the Government incentive / £5,000 grant. 

Magnitio

Eventually received quote from Octopus. Very thorough survey and quote. Total cost of over £11k, less government subsidy of £5k, plus some additional work that I would need to do means a cost to us of about £7k.

Based on their estimated energy consumption figures, but using the rates I currently pay for gas and electric, it would cost us an extra £280p.a. to run the heat pump. However, it would result in a reduction of 1.8 tonnes of co2 being emitted.

So, from a financial point-of-view, it makes no sense currently. As far as emissions are concerned, we have significantly reduced gas consumption over the past 12 months to about half previous years, but would obviously like to improve this even more.

matelodave

 I suppose it depend on what your priorities are, spending less or reducing your CO2.

Although TBH honest, I'm not sure how much you reduce your CO2 contribution when most of your leccy comes from  burning gas or wood pellets transported all the way from the USA  in gas fired or "biomass" power station which produces steam to drive a turbine to make leccy which is transported halfway across the country for you to convert back to heat. compared with burning the gas yourself in a 90% efficient boiler to produce the heat where you use it.

Granted that a heatpump might be 300% efficient but I really do wonder how much of that efficiency is lost between the power generation facility and its eventual delivery to your home.

Reed_Richards

Magnitio said:

So, from a financial point-of-view, it makes no sense currently. 

The running cost of an ASHP has never been clearly ahead of the running cost of a gas boiler; at current prices it's the closest it has ever been, and the ASHP might well win if you had underfloor heating throughout.  The hugely difficult issue, if you are replacing an old boiler, is how prices will change over the next 10 years or so.  30 months ago I made a decision based on the then price of oil and electricity and solely on the basis of current running costs it was the wrong decision.  But at least I can look out of the window and glimpse the tops of the wind turbines that are generating my electricity.  That doesn't have to travel far.     

Martyn1981

matelodave said:

 
Granted that a heatpump might be 300% efficient but I really do wonder how much of that efficiency is lost between the power generation facility and its eventual delivery to your home.

Hiya, if you're wondering, then using your figures, a 90% efficient boiler will turn 1kWh of gas into 0.9kWh(t) for space heating.

1kWh of gas through a CCGT at 55% efficiency, then 5-10% losses in transmission, will deliver 0.5kWh of leccy to the house, which at a COP of 3, will deliver 1.5kWh(t). So approx 67% more heat from the same amount of gas.

Plus of course, about 50% of our leccy is now from RE, and growing each year.

70sbudgie

https://www.carbonintensity.org.uk/ has a section on regional data. If you tap on the region you're interested in (I am in the NW), you can see a breakdown of the generation and also the supplying regions. The regional data is still beta, but interesting. (Imo).

So I can see that right now, the carbon intensity in the NW is 17gCO2/kWhr, 53.8% is from wind, 36.8% is from nuclear, but only 64.3% is supplied by the NW generators, the rest is from Scotland N and S, NE England and imports.

It is possible to then look up the generation mixes in the supplying areas. It becomes a bit of a rabbit hole, but an interesting one, that I've been down more than once!

Edit to add: my point is that you can check how green your electricity is and it will be heavily impacted by which DNO area you are in, as well as the weather. I live in a pretty low carbon generation area (relative to the rest of England), so know that more often that not heat pumps would be the lower carbon option for me.