Solar / renewable hot water and heating

matelodave

I'd bet that it's COP during the nigh is pretty close to 1 (ie you'll put nearly as much energy in as you get out) it's bound to be a lot better during the day with the sun on it. I'd guess that if it achieved a SCOP of around 2.5 then it would be included in the RHI payment scheme.

I really think that you are being swayed by the fact that it's new and innovative  technology (although it's not really) but it cannot be anywhere near the sort of performance you get from an AS or GS heatpump because it cant get as much heat out of the environment when the sun don't shine. I'd want a lot more real data rather than shiny brochure stuff  before lashing out £5k or more.
I spent a lot of effort and did a lot of my own calculations before I was convinced that my ASHP would be suitable and cost effective even without RHI which wasn't introduced for another four years. I got multiple quotes, a couple of which that were just blatantly stupid in terms of projected performance or even equipment sizing so you really need to do a lot more research and get quotes from others to compare.

Please let us know how it goes when you get one because we'll all be interested

MWT

tigertedd_2 said:

The whole point of this system is that it works at night, otherwise, it might as well just be a solar hot water system.

Focus on this bit:

In the sunshine you will get just that, cold liquid out, warm gas back and the bigger the temperature difference the more energy you will get back from the exchange.

The problem is that at night, although it will still work as the liquid has a low boiling point, you will be getting cold gas back which will deliver very little energy compared to what it can achieve with the help of the sun.

It will not perform as well as a normal ASHP over night as it lacks the fan (and possibly also the defrost capability).

It is being advertised as some sort of new and special technology, it really isn't, it is just an ASHP with a solar assist but no fans, so it is designed to be most efficient in the sun and relatively poor at night.

Talk to a good reputable installer about your options, ASHP or even GSHP may well be much better options depending on location and need.

tigertedd_2

matelodave said:

I'd bet that it's COP during the nigh is pretty close to 1 (ie you'll put nearly as much energy in as you get out) it's bound to be a lot better during the day with the sun on it. I'd guess that if it achieved a SCOP of around 2.5 then it would be included in the RHI payment scheme.

I really think that you are being swayed by the fact that it's new and innovative  technology (although it's not really) but it cannot be anywhere near the sort of performance you get from an AS or GS heatpump because it cant get as much heat out of the environment when the sun don't shine. I'd want a lot more real data rather than shiny brochure stuff  before lashing out £5k or more.
I spent a lot of effort and did a lot of my own calculations before I was convinced that my ASHP would be suitable and cost effective even without RHI which wasn't introduced for another four years. I got multiple quotes, a couple of which that were just blatantly stupid in terms of projected performance or even equipment sizing so you really need to do a lot more research and get quotes from others to compare.

Please let us know how it goes when you get one because we'll all be interested

So I’ve had a bit more info, there’s a 10 year guarantee, with no maintenance costs (so any required maintenance is included). 

Did you replace a Gas system with your air source? What I’ve read is that air source is a great alternative if you don’t have access to gas, but is ultimately about the same, or more expensive than gas, in terms of the cost of the electricity you have to put in. 

Also, we have had it checked, and there isn’t really anywhere suitable to put it on our house, so I’m not sure it would be an option for us anyway. 

With this the electricity is used for the pump As and when you need to refill your hot water tank, so it’s really not that much, but any electricity I do need will come off the battery (which if it doesn’t get its power from the panels, it will get its power from the grid at about 4p a unit Max).  

In a couple of years I’ll need to upgrade the battery anyway, as I’m hoping to run an electric car off it too. So then ill
make sure I’ve got one with a big enough capacity to cover the car, heating and hot water so we should hopefully never be paying more than that super low rate.
That’s the master plan anyway. 

Whether or not this thermodynamic panel, or the IR heaters, are the right solutions for the heating and hot water element of that master plan is the question. But given that air source isn’t really an option on our home, I think this is probably the best option. 

You’re right though, there’s more than a small element of ‘oo, it’s a new gadget, I must have it’ to my thinking. If I had to put it on a graph, it’s probably about 40% that, 30% environmental, 20% a fear of the future escalating cost of gas and electricity, and 10% about saving money (whether gas and electricity prices rise or not). 

I’m really just trying to justify in my own head that this new toy is worth the money somehow (cos as toys go, it’s quite boring, if it was 100% about a new toy, I could probably buy a quad bike or something). 

MWT

tigertedd_2 said:

So I’ve had a bit more info, there’s a 10 year guarantee, with no maintenance costs (so any required maintenance is included).

This is like any of the solar schemes or buying double-glazing... check who is offering the guarantee, how long the company has been in business and check the directors and see what other businesses they are currently directors of  and especially which businesses they have closed down over the years.

A 10 year guarantee from a company that has only been in existence for 2 years isn't worth much.

Check the accounts for the company as well and see if they are building value in the company or if everything is being syphoned off in 'Management Charges' or similar.

Check Facebook as well, their page will either be pure marketing with no happy customer posts or you'll find a happy community of customers. If it is pure marketing be suspicious, those with happy customers want them to post...

Also check the manufacturer and see where they are located, as if the company offering you the guarantee folds they will be your only hope for parts etc. (China I believe in this case).

I'd also try to be a little clearer about maintenance, just because they do not quote any maintenance cost doesn't mean that any maintenance is automatically covered. Lets say for example that birds or a something else damages a panel or a refrigerant line, does the supplier carry spare parts or are they just installing whole systems shipped from China? How and where do they recharge the refrigerant etc. 

Above all else get references and take them up, a few genuine users who have had the system through at least one winter should be able to give an honest assessment of the product...

... but of course it is your money so do let us know how it goes...

MWT

... and finally do a little digging around the net, these are not new systems, various companies have been trying to sell them in the UK for years now...

I've found references from 2017 in the UK talking about even older installations elsewhere and they seem to focus on the lack of certified performance figures etc.... here is one for example:

https://forum.buildhub.org.uk/topic/3615-bunsen-air-heat-pump-for-domestic-hot-water/

matelodave

My ASHP was installed as an alternative to Storage Heaters, LPG or Oil. We dont have mains gas anywhere close otherwise that would still be my preferred choice.

The heatpump and associated hot water tank cost me just over £7k ten years ago (an oil boiler, hot water tank and oil tank would probably have been around £4k, LPG might have been bit cheaper so we paid a premium of around  £3k at the time. We've had more than £4k back in RHI payments with about £750 still to come and I reckon my fuel bills are significantly lower than they would have been with Oil, LPG or even Storage Heaters.
I dont have any figures for them as we started ten years ago, gutting the place and installing the ASHP and underfloor heating as soon as we moved in but I'm happy that we made the right choice.
I dont have any hang-ups about being green or saving the planet, I just want to save money so I'm not going to spend more than I need just to give me a warm fuzzy feeling - cost and efficiency are my parameters.