Sunamp heat battery

[oranjeboom]

 PCM58 cells are the ones typically charged by a gas boiler and the PCM34 cells are low temp ones typically charged by PV and ASHP?

[Nickfromwales]

50 minutes ago, oranjeboom said:

 PCM58 cells are the ones typically charged by a gas boiler and the PCM34 cells are low temp ones typically charged by PV and ASHP?

Both charge off PV as happily as the other as a kW of input is a kW of input and always will be. The units are sized in kWh capacity so its black and white.

From my discussions the newer types, with the immersions nigh-on direct to the PCM, are pretty much a kW in = a kW stored, so for a rough eg a 9kW cell, regardless of type, should take between 3 and 3.5 hours at 3kW PV output to fully recharge. 

A gas boiler could charge either cell type, with the correct design and execution. 

 

@oranjeboom FYI I have two enquiries where the houses will be all electric all Sunamp. Both utilising the PCM58 with immersions so no ASHP / gas / oil / other. Both, however, will have substantial PV arrays to fortify grid ( economy ) electricity. Don't discount this option as its certainly very appealing in a low energy home   

[oranjeboom]

@Nickfromwales Thanks! I'd just started looking into Sunamp (again) when I came across your corrossion post, but seems this may not derail my plans then with the two cell types being 'multi-source'. I just need to get my head around your setup suggestions in my other thread!

[Nickfromwales]

32 minutes ago, oranjeboom said:

@Nickfromwales Thanks! I'd just started looking into Sunamp (again) when I came across your corrossion post, but seems this may not derail my plans then with the two cell types being 'multi-source'. I just need to get my head around your setup suggestions in my other thread!

Just work out what you need to know and bump the other thread  

[le-cerveau]

I have had an update from Andrew about the PCM34 cells I have, they have temporally suspended production due to an issue with a different cell (PCM88) that is still in development and as a caution halted the PCM34 cells until that issue is understood. 

 

The details are in the attached.

SunAmp PCM34 letter.pdf

 

 

[Guest Alphonsox]

23 minutes ago, le-cerveau said:

I have had an update from Andrew about the PCM34 cells I have, they have temporally suspended production due to an issue with a different cell (PCM88) that is still in development and as a caution halted the PCM34 cells until that issue is understood.

 

 

What an excellent response to your concerns - They really are a very professional company. There aren't many others that would provide a customer such a candid or detailed response.

[Onoff]

Very impressed by Sunamp's open approach and honesty. Let's face it you'd be happy dealing with them just on that.

 

 

[newhome]

Just up the road from me. @Nickfromwales you could have gone to visit while you were up! 

 

 

[Nickfromwales]

1 hour ago, newhome said:

Just up the road from me. @Nickfromwales you could have gone to visit while you were up! 

 

 

Could have yes, what with the short days and spare time we had  

[Simplysimon]

7 hours ago, Onoff said:

Very impressed by Sunamp's open approach and honesty. Let's face it you'd be happy dealing with them just on that.

 

 

i contacted them, was asked for plans which were sent. i said about ASHP and was told they have good returns with high temp ASHP, told them mine was low temp and have heard nothing since!

[Triassic]

I’ve also had a quote off Sunamp for a system to provide hot water and under floor heating, in conjunction with a high temperature ASHP.  The quote came back at over £7k for the Sunamp, then there’s the ASHP and the 4Kw of solar to add to that figure. It’s turning into a rather expensive approach.

 

Now going back to look at the price of a thermal store!

Edited April 29, 2018 by Triassic

[Nickfromwales]

1 hour ago, Triassic said:

I’ve also had a quote off Sunamp for a system to provide hot water and under floor heating, in conjunction with a high temperature ASHP.  The quote came back at over £7k for the Sunamp, then there’s the ASHP and the 4Kw of solar to add to that figure. It’s turning into a rather expensive approach.

 

Now going back to look at the price of a thermal store!

What size units did they quote / qty ?

[Nickfromwales]

10 hours ago, Simplysimon said:

i contacted them, was asked for plans which were sent. i said about ASHP and was told they have good returns with high temp ASHP, told them mine was low temp and have heard nothing since!

What are your fabric and ventilation heat loss figures? Two I've just spec'd have worked out better going all elecric via PCM58 cells. 

No ASHP to buy / install / maintain / replace, no noise and no antifreeze to dump and replenish every 5 years or so at ~£500 a go. Oh and you don't have a big wart on your outside wall either.   

 

The SA are still a very good option if you compare closely what you get for your money. They're recent removal from sale of the PCM34's is a bit of a game changer for anyone with / intending to fit an ASHP I agree so they need to get that crease ironed damn quickly, but the PCM58's are still ( to quote a member ) "a very elegant" solution. 

3-4 times the capacity for size compared to cylinders. Far lower losses. Modular boxes ( the 9kW and under fit under a kitchen worktop ) and no moving parts / components. 

38,000 cycles and 3.8% degradation is bloody good from where I'm sitting. 

@Simplysimon

Get the calculator out and see what your figures would look like if you needed no ASHP and could manage on E10. Reduces the cost of the SA units then to . You can buy a lot of E10 with the total savings !!

[pdf27]

Probably a question for @AndyT - the "Smart Heat Batteries" presentation temperature range chart shows an actual/potential temperature point at 43°C: do you know if this is either commercially available or planned to be so in the near/intermediate term?

The reason I'm interested is that 43°C is a good match to the maximum scald-safe hot water temperatures without being out of the efficient range for a heat pump, so a Stack unit with this material looks like it would be an excellent way to provide hot water from a heat pump, something I'm likely to be interested in doing in ~12-18 months time.

[TerryE]

On 17/04/2018 at 12:34, Nickfromwales said:

@oranjeboom FYI I have two enquiries where the houses will be all electric all Sunamp. Both utilising the PCM58 with immersions so no ASHP / gas / oil / other. Both, however, will have substantial PV arrays to fortify grid ( economy ) electricity. Don't discount this option as its certainly very appealing in a low energy home   

 

To be honest our twin SunAmp configuration + Willis for UFH is working very well and we are very pleased with it. OK, the planning restrictions on PV means that we lose 8 points off our SAP rating, IIRC, but the running costs are so low it's going to be hard to make a case for an ASHP.

Edited May 15, 2018 by TerryE

[jack]

10 hours ago, TerryE said:

... but the running costs are so low it's going to be hard to make a case for an ASHP.

 

And that's assuming nothing goes wrong!

 

Our ASHP blew a control board before Christmas. Cheapest I can find a replacement board: £170

 

It's highly recommended that you change the pump at the same time, because it's the most likely reason for the failure, and isn't easily tested. Cheapest I can find a replacement pump: £380 

Then there's the cost of troubleshooting the problem and doing the repair. I haven't had this priced separately, but I can't see anyone with the relevant qualifications doing it for less than a couple of hundred quid.

 

Let's call it £750 in total. The ASHP itself only cost £1700!

 

By way of background, I've had an authorised Panasonic engineer check our setup and installation and he confirmed that everything seems fine. The only potential issues are that we hadn't been running glycol (now fixed) and it was spending several months completely idle over summer due to our Immersun covering all hot water over that period. There's a setting that turns the pump on for a couple of mins a day whether or not heating or cooling is needed, to keep things moving - that might help longer term.

 

The installation was only 2.5 years old. Installations done by an authorised Panasonic engineer come with a 5 (sometimes 7, if you get them during a promotion) year warranty, so possibly worth paying the extra up front.

 

But back to your point @TerryE, yes, an immersion-only system is looking very appealing to me at the moment! 

[TerryE]

My only tweak that I am currently thinking of is to double up on the Willis -- mainly to remove a single point of failure, but also allow me to put in more heat overnight (E7) if we do get a long sub-zero spell in the depths of winter. 

 

At the moment we have almost nothing in our design that requires regular (££) maintenance.  We need to clean the MVHR filters quarter and replace the secondary filter on the MVHR annually.  That's all really.

[Triassic]

On 29/04/2018 at 08:36, Nickfromwales said:

What size units did they quote / qty ?

 

Theyve quoted that I need 2 of the UniQ eDual 12 units at a total cost of £7,250. This is to provide ufh heating and hot water in a four bed house with three bathrooms and a kitchen, occupied by two people.

 

They’ve  also included their calculations which I need to double check against my heat loss calculations.

[Nickfromwales]

2 hours ago, Triassic said:

 

Theyve quoted that I need 2 of the UniQ eDual 12 units at a total cost of £7,250. This is to provide ufh heating and hot water in a four bed house with three bathrooms and a kitchen, occupied by two people.

 

They’ve  also included their calculations which I need to double check against my heat loss calculations.

How much PV ?

[Triassic]

3 hours ago, Nickfromwales said:

How much PV ?

4kWp of in roof panels.

[Nickfromwales]

40 minutes ago, Triassic said:

4kWp of in roof panels.

Only ever going to be occupied by 2?

In fairness I think they've allowed for the capacity of the house rather than your needs. What's the max ventilation and heat loss per day for -10oC outside ? 

[Triassic]

18 hours ago, Nickfromwales said:

What's the max ventilation and heat loss per day for -10oC outside ? 

1

Results from the JCH spreadsheet using the input data for my proposed new house.at-10 DegC

 

[TerryE]

It depends where you live of course, but in the UK the number of days per year where the average temperature is below zero is small, and the number below -5°C is tiny.  I feel it is a mistake to optimise your heating for the worst case.  So what is the life expectancy and annual maintenance costs of your quoted eDual 12s?  I suspect 10 years and 5% might be a good ballpark, or roughly £1K p.a. amortised cost. My total annual energy bill is just over that with my twin SAs and Willis heater and no PV.  And we also have a largish 4 bedroom house with 3 ensuites and a bathroom and 3 occupants.

 

We have UFH on the GFL only so the 1st floor does get about 2°C cooler than the ground floor when it gets really cold but we don't find this a problem for the bedrooms.  I do have a Dyson fan in my office, which might run for an hour or so on really cold days when I am working up in it.

Edited May 18, 2018 by TerryE

[oranjeboom]

2 hours ago, Triassic said:

Results from the JCH spreadsheet using the input data for my proposed new house.at-10 DegC

 

 

I was quoted for a 2 12kWh UniQ Heat units for space heating (and a 9kWh UniQ eHW for DHW charged by 3.8kW PV) and that is with double your heat loss:

 

 

I will have 180sqm (135sqm downstairs) of UFH to heat (with an ASHP) but suprising that you also have been quoted for 2 units @Triassic! Over-specced in your case as only half of my house is 'new-build'. Yours will be more airtight than mine and you also benefit from large south facing aspect iirc. It's a lot of money especially if I have to add on the ASHP also so I'm thinking to just get one 12kWh unit for space heating and see how that performs over winter. On those days that I see  -temps I could just plug in some electric heaters if necessary. If I do find I need another 12Kwh cell, then I can always fork out later for one. Haven't read all the SA material I have been sent tbh, but wondering how long a 12kWh cell takes to charge using an ASHP? If it's being charged overnight ready for the UFH to kick in say from 5am in the morning  for a few hours, then recharges during the day for late afternoon/evening demand, would a single 12kWh cell struggle to do that? I'm probably not being logical at all with my thinking there.

[Jeremy Harris]

Regarding charge time, it depends on the power output of the ASHP.  Our 6 kW ASHP would charge a 12 kWh unit in two hours, perhaps slightly less under ideal conditions when the ASHP can exceed 6 kW output, slightly longer under less ideal conditions when the output can drop a bit below 6 kW.