SunAmp : Snog, Marry, Avoid?

[LA3222]

4 hours ago, PeterW said:

Isn’t that what was the nail in the coffin for Solar Thermal though..?  PV came down in price to a point that it overtook ST. Same scenario here I expect in the next 2-3 years. 

This is exactly what I was thinking whilst catching up on this thread.  I think SunAmp has had its moment in the sun on this forum and newer members are looking at them qith a whole different set of glasses on.

 

The early adopters amongst the forum members were very enthusiastic and positive about SunAmp, which bleeds into and alters newer members thinking (not a bad thing as such). But I think the honeymoon period seems to now be over and the real experiences that members such as @Barney12 for one, have had has been somewhat deflating from what people hoped they would be.

 

Its been an interesting journey, but I think the argument for SunAmp is slowly being lost.  

[Onoff]

4 minutes ago, LA3222 said:

This is exactly what I was thinking whilst catching up on this thread.  I think SunAmp has had its moment in the sun on this forum and newer members are looking at them qith a whole different set of glasses on.

 

The early adopters amongst the forum members were very enthusiastic and positive about SunAmp, which bleeds into and alters newer members thinking (not a bad thing as such). But I think the honeymoon period seems to now be over and the real experiences that members such as @Barney12 for one, have had has been somewhat deflating from what people hoped they would be.

 

Its been an interesting journey, but I think the argument for SunAmp is slowly being lost.  

 

Isn't it that Sumamp moved the goalposts? They simply no longer do the models the happy early adopters had. Replaced by less flexible kit. 

[LA3222]

12 minutes ago, Onoff said:

 

Isn't it that Sumamp moved the goalposts? They simply no longer do the models the happy early adopters had. Replaced by less flexible kit. 

I'm not sure. The biggest issue seems to be maximising PV use, without rereading everything I can't recall if the PV charging was optimal early on or just better than it currently is?

 

I think SunAmp is good, but I'm starting to think that it is slightly one dimensional for its cost. 

 

The solar battle went the way of PV over thermal.

 

I suspect energy storage will go to Battery rather than phase change.

 

PV seems to be going down in price, I suspect battery storage will follow suit.

 

 

[MikeSharp01]

19 minutes ago, LA3222 said:

I suspect energy storage will go to Battery rather than phase change.

Then it all comes down to rate of delivery for DHW, there are electric combi boilers but the rate they deliver is pitiful - this one delivers 12L/M and needs a three phase supply, we need some massive kit that can deliver 20L/min at 50 deg C. You will have the potential current from the batteries - the average EV is many 10s of KW so not a problem energy wise it is down to getting it into the water fast enough.

[scottishjohn]

If there is life for PCM system then i think it will be on big scale for district heating and the like ,where waste heat from something can be collected and stored.

or maybe a heat pump extracting the heat from waste water  in winter to pump a very large pcm unit  and use in large heating system like a block of flats.

 or maybe solar thermal panels charging up a pcm unit in summer

I just don,t see it being great for small system --but  a large one

 

 Iran a solar thermal and tried to work out how to make the most of it --and storage was always the killer --the cost of it -

you can get  minimum30-40c water for a tleast 10months  of the year

-but you can,t store it at that cos tank will be so large

add heat pump to change it from 30-70c --now you are talking 

If they can make PCM units cheaper and with a wider range of temps to trigger it  then maybe  it could have a  longterm future 

Ionly see it viable on big scale 

 

[SteamyTea]

10 minutes ago, MikeSharp01 said:

the average EV is many 10s of KW so not a problem energy wise it is down to getting it into the water fast enough.

This is always a problem with inline heaters.

One way around that may be to deliver say 6 kW from the batteries and 10 kW from the mains.

Not idea, but would make for a decent enough shower.

Or just heat a small cylinder up slowly.  50 litres of 65°C water mixed with 30 litres of 10°C water should do it.

May need a small cylinder for each shower.  50 lt is a 0.36m cube.

[SteamyTea]

4 minutes ago, scottishjohn said:

I just don,t see it being great for small system --but  a large one

This is generally true for all storage, and generation for that matter.

4 minutes ago, scottishjohn said:

If they can make PCM units cheaper and with a wider range of temps to trigger it  then maybe

The thing about PCM is that the temperature is the same when it changes phase.  It is almost the definition of it.

[scottishjohn]

what Idid with my solar thermal was to store as hot as i could and have a blender on output of my tank so i used less of the hot and therefore less further mixing at shower --so saving waste of hot  by adding lots of cold to it at point of use

lots of days I could have had my 300 litre tank at 150c --but of course water cannot do that --

if  you linked an oil filled solar thermal to a pcm unit with high threshold ,as you can use different mixs to alter PCM change temp --then low flow/ high temp solar thermal might be a good match for a pcm unit --then heat exchanger on the pcm system to actually transfer heat  to the  water you want --

It gets complicated --very doable on big scale --

[joe90]

I think potentially PCM is a good technology (perhaps like @scottishjohn says in large scale) but it appears the controls are what let’s it down, I remember @Jeremy Harris playing with his and passing his findings back to sunamp to make it work better!!!,

Edited June 28, 2020 by joe90

[SteamyTea]

10 minutes ago, scottishjohn said:

what Idid with my solar thermal was to store as hot as i could and have a blender on output of my tank so i used less of the hot and therefore less further mixing at shower --so saving waste of hot  by adding lots of cold to it at point of use

As I was pointing out earlier, this does not always optimise the generation/storage combination.  It is that optimisation where thermal storage has a problem, almost regardless of scale.  Scaling really just reduces losses per unit stored.

 

10 minutes ago, scottishjohn said:

lots of days I could have had my 300 litre tank at 150c --but of course water cannot do that --

Yes you can, and you could make use of the latent heat as it changes from gas to liquid, it is how most solar thermal evacuated tubes work.  334 kJ/kg as opposed to 4.18 kJ/kg.

Would need a sturdy box to keep it in.

Edited June 28, 2020 by SteamyTea

[PeterW]

47 minutes ago, SteamyTea said:

Or just heat a small cylinder up slowly.  50 litres of 65°C water mixed with 30 litres of 10°C water should do it.

This is what’s found in a lot of Italian houses - localised cylinders. 
 

This is one example - in the U.K. this would have to have a G3 install plus have blow off valves etc 

[SuperJohnG]

I'd read bits and bobs over the last 6 months on sunamp and the last two pages of this thread. 

I still don't fully understand it...but there are far too many red flags and niggles for it to even be considered.  I'll be going 300L UVC with ASHP. reliable and you know what you're getting. 

 

I did consider gettinga 4kW PV and a divertor as I want to have some form of reducing energy consumption but from spending some time reading I'll never recoup the cost and seemed a bit pointless now? 

[Nickfromwales]

7 minutes ago, SuperJohnG said:

I did consider gettinga 4kW PV and a divertor as I want to have some form of reducing energy consumption but from spending some time reading I'll never recoup the cost and seemed a bit pointless now? 

Unless your array is north facing, I cannot see how PV would be a bad thing?!  Any PV company will have to give you a survey and forecast of performance / cost / break-even point ( based on deemed % of self consumption ) / and RoI  numbers for you to consider.

Have you had a proposal yet? If not, it would be a good paper exercise IMO, and should be free.

[ProDave]

21 minutes ago, SuperJohnG said:

I'd read bits and bobs over the last 6 months on sunamp and the last two pages of this thread. 

I still don't fully understand it...but there are far too many red flags and niggles for it to even be considered.  I'll be going 300L UVC with ASHP. reliable and you know what you're getting. 

 

I did consider gettinga 4kW PV and a divertor as I want to have some form of reducing energy consumption but from spending some time reading I'll never recoup the cost and seemed a bit pointless now? 

I think you are right to be skeptical. My DIY installed system cost £1500 and based on saving me £250 worth of electricity each year has a payback time of 6 years.  I would be impressed if you can get a system professionally installed for under £3k and you would be looking at a 10 year payback or longer.  Only you can decide what is worth it.

[Nickfromwales]

2 minutes ago, ProDave said:

looking at a 10 year payback or longer

And a system ( if not second hand from the outset ) that lasts 25 years minimum will therefore give 'free' electricity out for the next 15 years minimum. Most are warrantied for 25 years, Solarwatt for 30 with a 30 guarantee as well as warranty. The cheap stuff is likely to fail, so avoid the cheap seats where budget allows IMO.

It's down to whether or not you can utilise it and not waste sending it to export eg maximum self consumption.

[SuperJohnG]

1 hour ago, Nickfromwales said:

Unless your array is north facing, I cannot see how PV would be a bad thing?!  Any PV company will have to give you a survey and forecast of performance / cost / break-even point ( based on deemed % of self consumption ) / and RoI  numbers for you to consider.

Have you had a proposal yet? If not, it would be a good paper exercise IMO, and should be free.

I haven't actually. But I would buy direct and coordinate the install myself with my electrician. Id read @ProDaves experiences previously and it didn't make sense on payback terms however maybe I do need to look again as I presumed at wouldn't last 25 years. 

 

I've zero chance of coordinating consumption though I've two young kids and swmbo will think ive finally lost it putting in timetable for the washing machine. 

[Dan F]

14 hours ago, Barney12 said:

If you read the Sunamp twitter feed it suggests they now have partnerships with three ASHP manufacturers.

 

The partnership as far as I understand is that they've tested Sunamp with the ASHP and produced model-specific controllers. This means that when you order a Sunamp you have to order the right controller depending on which ASHP you plan to use.  I may have said this elsewhere, but the fact it is different hardware, and that changing your heat-source means you may need to get a different controller, it's unforfgivable in 2020 in my opinion.

 

Edited June 28, 2020 by Dan F

[MikeSharp01]

7 minutes ago, Dan F said:

I may have said this elsewhere, but the fact it is different hardware, and that changing your heat-source means you may need to get a different controller, it's unforfgivable in 2020 in my opinion.

Your right - the controller must be software cored and the interfaces common / industry standard so an accommodating controller seems obvious.

[DamonHD]

On 28/06/2020 at 08:40, SteamyTea said:

Like all storage, it needs to be empty to take advantage of cheap or free energy.

This may be OK for space heating, probably less so for DHW.

 

Has anyone compared the prices to battery storage?  If you are going to spend £3k to £5k on a Sunamp, it may not be so far off.

1.2kWh of my AC-coupled battery storage cost close to £3k including all work, for which I'd expect to get 7kWh of Sunamp heat storage.

 

Rgds

 

Damon

[Dan F]

23 minutes ago, DamonHD said:

1.2kWh of my AC-coupled battery storage cost close to £3k including all work, for which I'd expect to get 7kWh of Sunamp heat storage.

 

Batteries only? That sounds like an awful lot!  I have a quote for <£500/kWh AC-coupled incl labour.

[NSS]

5 minutes ago, Dan F said:

 

Batteries only? That sounds like an awful lot!  I have a quote for <£500/kWh AC-coupled incl labour.

 

That sounds close to tempting. Do you mind me asking what/whose kit it involves, please?

[Dan F]

Just now, NSS said:

That sounds close to tempting. Do you mind me asking what/whose kit it involves, please?

 

2 x Powerall2 @ £480/kWh.  If you get just one it's a bit more (given gateway is one-time expense) @ £560/kWh.

[SteamyTea]

37 minutes ago, DamonHD said:

1.2kWh of my AC-coupled battery storage cost close to £3k including all work

How long ago?

Because

11 minutes ago, Dan F said:

That sounds like an awful lot!  I have a quote for <£500/kWh AC-coupled incl labour.

 

[joth]

4 minutes ago, Dan F said:

 

2 x Powerall2 @ £480/kWh.  If you get just one it's a bit more (given gateway is one-time expense) @ £560/kWh.

 

To be fair, this is "how much battery storage can I get for £13,000?" which if very different to  "how could I usefully spend the £3000 I save by not going with a sunamp?".

 

To the latter, I think 2x PylonTech US2000B plus an inverter and installation might be possible around £6-700/kWh? (And easy to add more storage in future as prices drop).

 

 

 

[SteamyTea]

4 minutes ago, joth said:

£6-700/kWh

Could save me up to 50p a day.

But all sarcasm aside, I could put in a wet heating system and gave more control.

But for just me it is not worth it, yet.