Nuenta Energy Blade - Water Source Heat Pump

[canalsiderenovation]

Now we have an architect and are working on designs for our complete remodel, our attention has turned to our heating system which needs completely replacing - on oil currently, no mains gas. We want underfloor heating throughout so a heat pump is our preferred option. 

 

After a lot of research, research I started even before finding an architect we are taken with a water source heat pump given the canal side location of our property. We have a contact at the C&R Trust who have been helpful so far and our idea is a closed loop system and what we have read about the Nuenta Blades seem positive if we can get permission to site these in the canal bywash adjacent to our house (see pic) as there is continual flowing water. https://www.nuenta.com/viewproduct.asp?pid=109

 

It's a niche area but I wondered if anyone had any experience of these, either in their property, of fitting, maintenance etc etc. 

 

Obviously all early stages but there is lots of info on ashp and gshp and I'm curious on this technology with a heat pump. 

 

Any help or advice much appreciated. 

[Dreadnaught]

6 minutes ago, canalsiderenovation said:

we are taken with a water source heat pump given the canal side location of our property

 

I am sorry that I cannot help you directly but what a good idea! I recall seeing an implementation of this on one of the property programmes (was it Grand designs?) and it worked very well.

[canalsiderenovation]

Just now, Dreadnaught said:

 

I am sorry that I cannot help you directly but what a good idea! I recall seeing an implementation of this on one of the property programmes (was it Grand designs?) and it worked very well.

 

I can't recall ever seeing it on there but in seems a shame not to consider it, but trying to get any information is difficult. 

 

I have done so much research and from what I can gather is the COP is much higher with flowing water which means compared with an ASHP it is more effective and the RHI payments higher. Of course, trying to get someone to quote for such a system is yet to be explored and we are still negotiating with the C&R Trust too, but I'm keeping everything crossed we can actually make good use of this. 

[ProDave]

We have a burn flowing through our garden and I toyed with the idea of a water source heat pump. I didn't have anything expensive like that in mind just a loop of pipe down the burn and back up again (about 40 metres of length available) fed into a ground source heat pump.  The paperwork of getting permission from SEPA and more likely having to prove to BC that we had permission put me off and I went for a cheap ASHP instead.

 

I might still experiment in the future though.

 

I don't suppose you own both sides of that bywash do you?  An undershot water wheel looks like it might work there, another thing I am thinking of playing with later on.

[Dreadnaught]

@canalsiderenovation, I tracked it down. It wasn't Grand Designs, it was this:

 

https://www.houseplanninghelp.com/hph182-extracting-energy-from-watercourses-by-generating-electricity-and-extracting-heat-with-justin-broadbent-from-iso-energy/

 

Extracting energy from watercourses by generating electricity and extracting heat – with Justin Broadbent from ISO Energy. A podcast by Ben Adam Smith, the House Planning Help podcast.

 

Have you listened to it?

[canalsiderenovation]

15 minutes ago, Dreadnaught said:

@canalsiderenovation, I tracked it down. It wasn't Grand Designs, it was this:

 

https://www.houseplanninghelp.com/hph182-extracting-energy-from-watercourses-by-generating-electricity-and-extracting-heat-with-justin-broadbent-from-iso-energy/

 

Extracting energy from watercourses by generating electricity and extracting heat – with Justin Broadbent from ISO Energy. A podcast by Ben Adam Smith, the House Planning Help podcast.

 

Have you listened to it?

 

Thanks for this, I have indeed. I have had a lot of if formation on the blades from the ISO website already, https://www.isoenergy.co.uk/latest-news/isoenergy-news/cutting-costs-with-the-energy-blade-heat-collector Nuenta is the supplier of the blades. 

 

The information on the podcast was really helpful and made me more keen to explore it. 

 

It's ironic hydro has been mentioned @ProDave as this was something I initially explored, BUT the cost was likely to be huge. The red tape is very, very complex. Planning permission, abstraction licences, fish things and major environmental agency permissions all make this a non-starter. In addition, whilst the flow is sufficient, we don't have the drop at all. Our property is adjacent to the canal and the bywash is on our side (see pic). 

 

Now water source closed loop like the blade, no planning permission, no abstraction licence, very little red tape as long as the c&r trust are on board. 

[Dreadnaught]

What a lovely location!

 

6 minutes ago, canalsiderenovation said:

Now water source closed loop like the blade, no planning permission, no abstraction licence, very little red tape as long as the c&r trust are on board. 

 

 

I am curious, how would this work in practice? Would the blades be in the bed of the main river? In a rivulet? Or might the water by piped from the river and back through a tank (or some such contraption)? 

[canalsiderenovation]

Well just now Nuenta had replied to my email and have offered a site visit to look at the potential for mounting and give some advice about installing in the canal (they aren't a million miles away so this will be helpful in determining if it is an possible option). 

 

I'll keep you posted in the meantime as it's helpful if anyone else is exploring this option. In the meantime some documents attached that may explain it better than I can with the case studies too. 

Nuenta_Energy_Blade_Datasheet_1 (1).pdf

Nuenta_Energy_Blade_case_studies_1_(2).pdf

[Dreadnaught]

Interesting.

I suppose the use of such a system does present a conundrum.

 

With a well-insulated airtight house of modest size (I don't know if that is what you are considering), the energy demand for space heating is rather low. Energy demand for domestic hot water can often be similar of higher than for space heating. But a heat pump struggles to generate heat sufficient for domestic hot water (DHW). A 34º SunAmp preheat solution for DHW is one solution. Or a multi-stage heat pump but then the CoP suffers.

 

I assume this would also apply to a w/w heat pump. Might you have access to much more energy than you need? Or perhaps you are considering a less energy-efficient home and therefore could use copious hot water at 34º for space heating?

 

I assume a w/w heat pump would however offer a few advantages as well as access to copious energy, much better CoP in summer and winter compared to an ASHP for cooling and heating.

 

(And there is the question, of course, is if the extra cost is justified for the benefit.)

Edited October 1, 2018 by Dreadnaught

[canalsiderenovation]

4 minutes ago, Dreadnaught said:

Interesting.

I suppose the use of such a system does present a conundrum.

 

With a well-insulated airtight house of modest size (I don't know if that is what you are considering), the energy demand for space heating is rather low. Energy demand for domestic hot water can often be similar of higher than for space heating. But a heat pump struggles to generate heat sufficient for domestic hot water (DHW). A 34º SunAmp preheat solution for DHW is one solution. Or a multi-stage heat pump but then the CoP suffers.

 

I assume this would also apply to a w/w heat pump. Might you have access to much more energy than you need? Or perhaps you are considering a less energy-efficient home and therefore could use copious hot water at 34º for space heating?

 

I assume a w/w heat pump would however offer a few advantages as well as access to copious energy, much better CoP in summer and winter compared to an ASHP for cooling and heating.

 

(And there is the question, of course, is if the extra cost is justified for the benefit.)

 

You've hit the nail on the head there. 

 

Exactly our problem. Coming from gas previously or even the current oil system we love a hot steamy bath and hot water. We are what you'd say 'nesh' and I, coming from my parents who have an aga and continually heated house, every house I've ever lived in since hasn't t had the constant heat I was brought up witj. We are typical 'always cold' people and I love a nice hot steamy bath and don't know if the system will do this, but then I'm not convinced an Ashp will either, but we do know we want underfloor heating throughout, my brother has it and I love it. 

 

This technology is without anything else such as solar etc, obviously we need to get some figures and go from there and compare with Ashp. 

 

 

[ProDave]

30 minutes ago, canalsiderenovation said:

 

... I love a nice hot steamy bath and don't know if the system will do this, but then I'm not convinced an Ashp will either, but we do know we want underfloor heating throughout, my brother has it and I love it. 

 

This technology is without anything else such as solar etc, obviously we need to get some figures and go from there and compare with Ashp. 

 

 

My ASHP is heating my DHW to 47 degrees. This was found by experiment over a few days to be the absolute hottest I could hold my hand under without it being painful. Hot enough for washing up. Bathwater will be cooler with cold water added.

 

So an ASHP seems perfectly capable of heating DHW. The caveat being I fitted a larger hot water cylider as you will be diluting with less cold, so will need a greater volume of hot water.

[Stones]

Our ASHP based system has performed very well, plenty of DHW for a 'hot steamy bath' and keeps the house toasty warm for pennies.

 

For detail see this blog entry

 

 

[ragg987]

2 hours ago, Dreadnaught said:

But a heat pump struggles to generate heat sufficient for domestic hot water (DHW)

Not my experience at all. Ours can heat to 50C regardless of outside temperature. Sunamp for storage is a separate subject, 50C is too low for the regular PCM, and the 34C PCM is not hot enough for DHW. We use a 300l cylinder, the only downside is that recovery time is slow with our small heat pump.

[canalsiderenovation]

That's really interesting, I'm just about to read your blog @Stones. I have a visit from Nuenta in two weeks so I'll certainly ask the questions re hot water. It's reassuring to know a ashp can give the hot water needed. I guess we just need to review figures for ashp and the blade water source, though the water source has higher rhi payments. 

[PeterW]

I think the only issues with the water blade system are that it needs a deep flow - over 600mm - and it needs clear water free of debris. Does the spillway run 365 days a year ..?? It will only be 150mm at most I expect too so you will need to put some sort of pond system in to get the depth for the blades. 

 

Most if not all ASHP can do 50c, the HT versions go to 55c plus, usually using an immersion or direct element. The downside is the CoP drops to near 1 so unless you use it on E7 and,as has been said, have a big store then you may hit problems.  

[jack]

On 01/10/2018 at 18:23, ragg987 said:

Not my experience at all. Ours can heat to 50C regardless of outside temperature. 

 

Agreed. I haven't experienced any issues with our 5kW heat pump getting our 250L tank to 55 deg C, regardless of external temperature, even early in the morning on the depths of winter. it manages this while keeping the house as warm as I can bear it (my wife would have it warmer).

 

What I haven't checked, though, is how long it spends defrosting to achieve this in cold damp weather. 

 

We did have the circulating pump go in ours after only 2.5 years. The guy who repaired it suggested only heating to 50, as it takes a lot of time to get the last few degrees, which might have put undue pressure on the pump.

 

 

[canalsiderenovation]

1 hour ago, PeterW said:

I think the only issues with the water blade system are that it needs a deep flow - over 600mm - and it needs clear water free of debris. Does the spillway run 365 days a year ..?? It will only be 150mm at most I expect too so you will need to put some sort of pond system in to get the depth for the blades. 

 

Most if not all ASHP can do 50c, the HT versions go to 55c plus, usually using an immersion or direct element. The downside is the CoP drops to near 1 so unless you use it on E7 and,as has been said, have a big store then you may hit problems.  

 

The bywash depth is definitely more than 600mm having stuck a pole into it it went deeper than that, but how deep I don't know and will need to check (more pics attached for clarity from different angles). 

 

From our time and our neighbours the bywash has always had continuous flow, there are three locks the other side of that bridge and 5 mins walk the staircase locks too. 

 

I guess once the Nuenta guy visits I'll have more info on if such a system is even viable where we want to put it, and then it'd looking into the figures and comparing it to an ashp. 

[canalsiderenovation]

As an update to this, very interesting visit with the Nuenta rep, the sticking point is the depth which is minimal in the bywash. I'd definitely be keen to use the blades but they would have to be just after the bywash into the canal but we really need to get advice from the Canal and River Trust but trying to get anyone to respond to emails or phone calls is impossible. It would be easier to context Santa Claus! The technology and concept is however really good and we are most certainly going to try and pursue this. 

[Haz]

Hi,  has anyone had this installed?  We are bow looking into this...

[canalsiderenovation]

13 hours ago, Haz said:

Hi,  has anyone had this installed?  We are bow looking into this...

Nope afraid not for me. CRT were very difficult and it would have costs thousands of pounds to even get their involvement to consider. We ended up with ASHP.