Are ASHP the way to go?

70sbudgie

If there is already a DHW tank, how could you check if it would be compatible with an ASHP?

matt_drummer

Mstty said:

@matt_drummer how much electricity have you exported 1st Sept til today. 

I think from memory you have large battery storage to store it for ASHP use this winter.

We started today with the batteries 60% full.

We have our air to air heating on at the moment and have just done two loads of washing.

The batteries are full.

We have generated 30 Kwh so far today and still going, the house has used 8 kwh (from solar and battery) and we have exported 10 kwh.

We have used £0.99 in gas and electricity (including standing charges)

We are still generating a 4 Kwh at the moment.

It's all looking quite good
 

Mstty

matt_drummer said:

Mstty said:

@matt_drummer how much electricity have you exported 1st Sept til today. 

I think from memory you have large battery storage to store it for ASHP use this winter.

I can't answer that.

We moved to this house in September 2021 and it had a 4 Kwp system installed in 2014.

I receive the FIT payments and we are on deemed export.

I have no way to know how much of what we generated that we used, I know we imported 1,650 Kwh in 2022.

I have added another 6 Kwp of panels in the last month and 38 Kwh of usable battery storage.

Our existing panels generated 4,100 Kwh in 2022

I have estimated our generation for the year based on the new panels and the evidence so far is that they are performing better than I expected.

I will never know whether it fully works until I have some more time with it.

I do know that our gas usage last year was 12,500 Kwh.

If my boiler is 90% efficient that equates to 11,250 Kwh of heat.

I would expect to use 3,750 Kwh of electricity to run the heat pump at a SCOP of 3.00. 

I hope we can do better than a SCOP of 3.00, the house is very well insulated and doesn't lose heat quickly, I hope we can run a low flow temperature.

I haven't done this for monetary reasons, it helps to make it possible, but it has just become a bit of a challenge to make it work.

I am sure it will and if anybody is interested I will update this as I go along.

Now the solar and batteries are done I will start recording the data  from 1 April onwards (at a basic level) and see how close I was to getting it right!

That sounds like statistical analysis heaven to me, quite jealous tbh lol

Two things, In the first year you will make ASHP mistakes on setup and running and aim for efficiency in the second year of ownershi.

Second thing have you been running you gas CH when needed as in around work times or has it been running throughout the day? This is where your efficiency will decrease with an ASHP if using morning for a blast and evening for a blast. However if you have factored in running it low and slow round the clock in winter then all good.

matt_drummer

Mstty said:

That sounds like statistical analysis heaven to me, quite jealous tbh lol

Two things, In the first year you will make ASHP mistakes on setup and running and aim for efficiency in the second year of ownershi.

Second thing have you been running you gas CH when needed as in around work times or has it been running throughout the day? This is where your efficiency will decrease with an ASHP if using morning for a blast and evening for a blast. However if you have factored in running it low and slow round the clock in winter then all good.

I'm an accountant, I'm Ok with numbers.

I hope I don't sound like I am bragging or overly rich! I borrowed to do most of it and I know I am fortunate to be able to do that. I couldn't have done it if I thought it would have a massive cost over it's lifetime.

I will be happy if we break even and my only gain is not burning stuff, that is my goal.

I think the stats will be quite interesting but I don't intend to go into quite as much detail as some people do on youtube.

I think it's a great project for me, especially as I hadn't planned to do this at all.

I hope it will be useful to post my progress but if anybody objects I will stop.

I am sure there will be a learning curve with the heat pump, there is with the batteries and panels, I'm addicted to watching how it all performs at the moment, I hope I can get back to normal and do some other stuff soon!

I will not sit here cold and if I lose efficiency, then so be it. We have the back up of air to air throughout the house so if I get it wrong that can pick up the slack.

I could have stuck with air to air (I will keep it all, of course, for cooling in the summer and insurance for the winter) but I don't really like it as a heating source.

Our central heating is on constantly in the heating months, it just sets back a little overnight.

I will be running the ASHP 24/7, I know it's how it will work best. A lot of the problems stem from expecting them to behave like gas or oil boilers.

I am confident it will all work.

matt_drummer

70sbudgie said:

If there is already a DHW tank, how could you check if it would be compatible with an ASHP?

My current system is a vented system boiler, the DHW tank has to go.

I think you would need a pressurised system as minimum.

Although, thinking about it, I think you have to have a special tank with large coil inside to transfer the heat from the pump to the water in the tank.

Unless somebody knows better, I think you have to have a special tank for ASHP's.

matt_drummer

Mstty said:

Out of interest do you or anyone else know who Octopus got into bed with to make their ASHP I wonder what's under the hood.

Their heat pumps are Daikin.

I guess Octopus heat pump buyers will benefit from their buying power.

70sbudgie

matt_drummer said:

Mstty said:

That sounds like statistical analysis heaven to me, quite jealous tbh lol

Two things, In the first year you will make ASHP mistakes on setup and running and aim for efficiency in the second year of ownershi.

Second thing have you been running you gas CH when needed as in around work times or has it been running throughout the day? This is where your efficiency will decrease with an ASHP if using morning for a blast and evening for a blast. However if you have factored in running it low and slow round the clock in winter then all good.

I'm an accountant, I'm Ok with numbers.

I hope I don't sound like I am bragging or overly rich! I borrowed to do most of it and I know I am fortunate to be able to do that. I couldn't have done it if I thought it would have a massive cost over it's lifetime.

I will be happy if we break even and my only gain is not burning stuff, that is my goal.

I think the stats will be quite interesting but I don't intend to go into quite as much detail as some people do on youtube.

I think it's a great project for me, especially as I hadn't planned to do this at all.

I hope it will be useful to post my progress but if anybody objects I will stop.

I am sure there will be a learning curve with the heat pump, there is with the batteries and panels, I'm addicted to watching how it all performs at the moment, I hope I can get back to normal and do some other stuff soon!

I will not sit here cold and if I lose efficiency, then so be it. We have the back up of air to air throughout the house so if I get it wrong that can pick up the slack.

I could have stuck with air to air (I will keep it all, of course, for cooling in the summer and insurance for the winter) but I don't really like it as a heating source.

Our central heating is on constantly in the heating months, it just sets back a little overnight.

I will be running the ASHP 24/7, I know it's how it will work best. A lot of the problems stem from expecting them to behave like gas or oil boilers.

I am confident it will all work.

Perhaps when you get the quote and decide to move forward, it will be worth setting up a dedicated post? That way, those of us that are interested can easily find your story.

matt_drummer

70sbudgie said:

Perhaps when you get the quote and decide to move forward, it will be worth setting up a dedicated post? That way, those of us that are interested can easily find your story.

That's a good idea, thank you.

I hope that won't be against any forum rules?

70sbudgie

matt_drummer said:

70sbudgie said:

Perhaps when you get the quote and decide to move forward, it will be worth setting up a dedicated post? That way, those of us that are interested can easily find your story.

That's a good idea, thank you.

I hope that won't be against any forum rules?

There are a few "case study" posts over on the "Green" board.

matelodave

matt_drummer said:

70sbudgie said:

Perhaps when you get the quote and decide to move forward, it will be worth setting up a dedicated post? That way, those of us that are interested can easily find your story.

That's a good idea, thank you.

I hope that won't be against any forum rules?

I shouldn't think so.

TBH there's not enough info around from people who have actual experience of installing and running a heatpump rather than a lot of hype and hearsay. Many of the threads get bogged down with all manner of comments and opinions, so one dedicated to a specific installation could be very useful, so go for it.

They do take a bit of getting used to but if you are prepared to put in a bit of effort then they do work and work pretty well.

I'm sure there are a lot of people who would value reading about your experiences as it would help them, both with their decision making but also how you get on setting it it up and operating it.