How do Sunamp heat batteries work?

waqasahmed

So, essentially the above. Can they work with heat pumps? 

Is the idea that they basically store energy overnight, ready for use in the morning? Would that energy be enough for winter too? Ie: for more than just water heating? 

I'd love to finally get away from gas entirely. This is also something I'd do after getting an MVHR and doing general air tightness work 

2nd_time_buyer

I think a more direct solution would be a heat pump hot water tank e.g.

Edel Hot Water Heat Pump | Dimplex
Ariston Products: Heat Pump Water Heaters Range | Ariston

Possibly in combination with an air-to-air heat pump

But in answer to you firs question, from their FAQs:

Can a heat pump be combined with a Sunamp heat battery?
Yes. Specific models in the Sunamp Thermino and UniQ battery ranges are compatible with heat pumps from Daikin, Samsung and Vaillant. 

We have tested the ability of the heat pumps from these manufacturers to meet the flow temperatures requirements of the heat battery (63-65 degrees Celsius).

QrizB

waqasahmed said:

So, essentially the above. Can they work with heat pumps?

Sunamp say they can.

The question you need to ask yourself, however, is exactly what are you trying to achieve, and how will a Sunamp-style heat battery help you achieve it?

Hazarding a guess, you're wondering if you can run a heat pump on cheap off-peak electricity to charge a thermal store, then use that stored heat to heat your home and hot water during the following day. You'd need to look at how much heat you'd need to store to achieve this, and how large a thermal store you'll need, then optimise cost vs. volume for a phase-change store vs. a big hot water tank (vs. just running the heat pump for heat when you need it without the store).

Martyn1981

waqasahmed said:

So, essentially the above. Can they work with heat pumps? 

Is the idea that they basically store energy overnight, ready for use in the morning? Would that energy be enough for winter too? Ie: for more than just water heating? 

I'd love to finally get away from gas entirely. This is also something I'd do after getting an MVHR and doing general air tightness work 

You could scale up, and they have a number of products, but looking at their hot water units, they are very expensive. Good product, good idea, but a lot of money.

I sat in on a sale visit at my sister's for a new heating system, in which they suggested the Sun Amp water heater (though the salesman didn't know it was Sunamp, and after I asked him for the third time, he simply passed me a brochure which confirmed it was Sunamp, I think he was new).

Anyway the price for a large water tank was about £4k, I suggested they'd be better off putting £3k in a savings account, and buying a 'normal' high quality tank. He said it would cost more to do that as the phase change storage meant no losses. I suggested that losing 1kWh per day from April to Sept*, was only about £25 (before leccy prices went nuts), so it would take 120yrs to make up the extra costs, or never if you earn 1% interest.

*He argued for 365 days, but I explained that during the heating months, the losses are within the building, so still heating, especially as he was trying to sell a leccy heating system for the property.

waqasahmed

Martyn1981 said:

waqasahmed said:

So, essentially the above. Can they work with heat pumps? 

Is the idea that they basically store energy overnight, ready for use in the morning? Would that energy be enough for winter too? Ie: for more than just water heating? 

I'd love to finally get away from gas entirely. This is also something I'd do after getting an MVHR and doing general air tightness work 

You could scale up, and they have a number of products, but looking at their hot water units, they are very expensive. Good product, good idea, but a lot of money.

I sat in on a sale visit at my sister's for a new heating system, in which they suggested the Sun Amp water heater (though the salesman didn't know it was Sunamp, and after I asked him for the third time, he simply passed me a brochure which confirmed it was Sunamp, I think he was new).

Anyway the price for a large water tank was about £4k, I suggested they'd be better off putting £3k in a savings account, and buying a 'normal' high quality tank. He said it would cost more to do that as the phase change storage meant no losses. I suggested that losing 1kWh per day from April to Sept*, was only about £25 (before leccy prices went nuts), so it would take 120yrs to make up the extra costs, or never if you earn 1% interest.

*He argued for 365 days, but I explained that during the heating months, the losses are within the building, so still heating, especially as he was trying to sell a leccy heating system for the property.

Ahhh thanks for that 

Tbh, a heat pump / any kind of thermal storage is something that is at the end of my energy strategy

I intend to :
Have more solar panels + batteries
MVHR
Air tightness 
Upside my radiators if needed

My house is already fairly well insulated, reaching EPC C prior to getting solar panels for instance 

And then a heat pump after all that 

waqasahmed

2nd_time_buyer said:

I think a more direct solution would be a heat pump hot water tank e.g.

Edel Hot Water Heat Pump | Dimplex
Ariston Products: Heat Pump Water Heaters Range | Ariston

Possibly in combination with an air-to-air heat pump

But in answer to you firs question, from their FAQs:

Can a heat pump be combined with a Sunamp heat battery?
Yes. Specific models in the Sunamp Thermino and UniQ battery ranges are compatible with heat pumps from Daikin, Samsung and Vaillant. 

We have tested the ability of the heat pumps from these manufacturers to meet the flow temperatures requirements of the heat battery (63-65 degrees Celsius).

I guess I could "charge" those heat pump thermal stores on a night time tariff?

And then send that energy again, into an ASHP? 

2nd_time_buyer

waqasahmed said:

2nd_time_buyer said:

I think a more direct solution would be a heat pump hot water tank e.g.

Edel Hot Water Heat Pump | Dimplex
Ariston Products: Heat Pump Water Heaters Range | Ariston

Possibly in combination with an air-to-air heat pump

But in answer to you firs question, from their FAQs:

Can a heat pump be combined with a Sunamp heat battery?
Yes. Specific models in the Sunamp Thermino and UniQ battery ranges are compatible with heat pumps from Daikin, Samsung and Vaillant. 

We have tested the ability of the heat pumps from these manufacturers to meet the flow temperatures requirements of the heat battery (63-65 degrees Celsius).

I guess I could "charge" those heat pump thermal stores on a night time tariff?

And then send that energy again, into an ASHP? 

Yes, to charging the heat pump thermal store on a night time tariff - that would give you hot water. I would be inclined to run the air-to-air heat pump on a combination of cheap night time energy and solar that would otherwise be exported (i.e. setting a timer for the middle of the day). The air-to-air heat pump would work best in a well insulated house where the fabric of the house itself acts as thermal store, and soothes over periods where the pump is not running. It is what I have being doing in our own house this autumn/winter and seems to be working well and so far have not had to switch on the central heating.

In the summer you might want to heat the hot water on solar during the day switch to an export tariff that pays a higher rate. Lots of variables but you get the gist(?).

Solarchaser

I looked at sunamp, but decided against as there is energy lost in the phase change, you can find this fact if you really really do a lot of searching from the ceo, Andrew Bissel I think it appeared in 1 presentation he did.
But more importantly,  the heating element inside the sunamp is really small, 2.8kw iirc and so heating the larger sunamps on short off peak would have been problematic. 
That was what finally turned me off sunamp.
Tepeo and warmstone are similar, but both have higher heating elements. 
They all seem to emphasise their thermal retention or great insulation properties,  but you have to do some digging to find the conversion losses.

Heating directly into water and drawing heat back out of that water seemed to me to have the lowest conversion losses...

Edit. Element is 2.8kw, not 1.8kw as I originally stated 

Reed_Richards

waqasahmed said:

So, essentially the above. Can they work with heat pumps? 

Their standard product would not work well with a heat pump (assuming you heat it by passing water from the heat pump through it).  This is because the phase change temperature (56 C from memory) is too high.  Apparently they do have a product for heat pumps that has a lower phase change temperature but you would have to be sure to specify that and I don't know if there is a cost penalty.

I think @Solarchaser is wrong, you cannot "lose" energy, the worst case is that it gets converted to some sort of vibration but even that would ultimately be converted to heat (although possibly not where you want it),  More likely the "lost" energy gets directly converted to heat but that can't be a problem.

A conventional thermal store is a tank full of water.  By comparison, a Sunamp thermal store is more compact, probably better insulated (although you will always lose heat down the connecting pipes), lighter and more expensive.      

Solarchaser

Haha there is always one, yes of course energy cannot be lost, but if you have the energy you want to remain in the phase change material and it does not, then it is lost in the conversion,  ie it does not come back out as the heat you want.

Like home batteries, some of the energy charge is *lost* in heat

Martyn1981

Solarchaser said:

Haha there is always one, yes of course energy cannot be lost, but if you have the energy you want to remain in the phase change material and it does not, then it is lost in the conversion,  ie it does not come back out as the heat you want.

Like home batteries, some of the energy charge is *lost* in heat

Yeah, if the heat is within the fabric of the building, and during heating periods, then like the hot water tank losses, it's ok, but if you're right about losses (even small), then the irony is huge, as that's the main benefit, as I understand it. That's to say, Sunamp say the heat is stored until needed without the losses of a conventional tank.

No free lunch I suppose.