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Author Topic: Magic Thermodynamic Box  (Read 538 times)

Shinding

  • Joined Jul 2016
  • West Wales
Magic Thermodynamic Box
« on: February 10, 2017, 04:19:20 pm »
Has anyone heard of, or more specifically have experience of, thermodynamic boxes (also know as the magic thermodynamic box!!)? A solar PV engineer recommended it today when my husband and I were looking into renewables for heating hot water - the boxes apparently use differences in the ambient air temp to heat hot water all year round. Electricity costs for the pump should be less than £100 a year.

I'm always wary of using something that is fairly new on the market and seeing as I have never heard of this I thought I ask on the ASH forum.

Hope someone has some info that may be of help to us.

Thanks.
Shinding

Womble

  • Joined Mar 2009
  • Stirlingshire, Central Scotland
Re: Magic Thermodynamic Box
« Reply #1 on: February 10, 2017, 05:30:50 pm »
Well, as a Process Engineer who's had an otherwise very boring day at work, I can hardly resist the lure of a magic thermodynamic box, can I!?  :D

So, repeat after me:

Heat won't pass from a cooler to a hotter
You can try it if you like but you far better notter
'Cos the cold in the cooler with get hotter as a ruler
'Cos the hotter body's heat will pass to the cooler

Heat is work and work's a curse
And all the heat in the Universe
Is gonna cool down 'cos it can't increase
Then there'll be no more work
and there'll be perfect peace
Really? Yeah - that's entropy, man!


A quick internet search came up with this: Thermodynamic Panels from the Magic Thermondynamic Box. The website is a little vague on the technical details, but from what I can gather, it's an air source heat pump, that also gets a bit of a leg up from solar heat gain.

Heat pumps are well established technology - you've got one in your kitchen that you use to stop your milk from going off  :). The only difference between this sort of heat pump and a domestic fridge is that instead of extracting heat from the inside of the fridge and rejecting it to the black coily thing round the back, you're extracting low grade heat from the outside air, sort of magnifying it, and then rejecting it into your water cylinder.

The 'magic' (hint: it's not magic) thing about your nifty box is that instead of just extracting heat from the air, it also catches a bit of solar energy and extracts the heat from that too.

So yes, both of these are well established technologies. As to whether it's the right thing for you, that's another matter.

If it were me, I'd be looking at how I heat my water at present, and would then try to make an estimate of how much that costs me per year. Then I'd compare that with the cost of the magic box, and its running costs of £100 per year (I'd want more evidence before trusting that figure too much though!)

Air source heat pumps typically have a coefficient of performance of roughly 3.5 (i.e. for every unit of electricity you put in, you get 3.5 units worth of heat out). Some are a bit better than that, and some are worse, but that seems to be a reasonable figure for estimation purposes. What that also tells you that no matter how magic the box is, the best it can do is reduce your energy consumption by about 2/3 compared with just using a standard twenty quid immersion heater. Also, if you're already using something cheaper than electricity to provide your hot water, you may not actually save money, especially once installation costs are taken into account.

So in summary, yes, it's well established technology. However, whether it's right for you, will depend on your own circumstances and the overall cost of installing the system.

We went through a similar exercise recently for another type of renewable system, and TBH I was seriously unimpressed with the downright lies told by some of the salesmen. Their calcs showed us being £35K better off over seven years. My honest-as-I-could-get-them calcs made it nearer £800. Caveat emptor!

So, I hope that helps! If not, it brightened up my afternoon at least!  :roflanim:
Experience is what you get just after you needed it.

Shinding

  • Joined Jul 2016
  • West Wales
Re: Magic Thermodynamic Box
« Reply #2 on: February 10, 2017, 07:17:20 pm »
Ha ha - glad I cheered you up Womble and thanks for your reply. Why did the company have to call it the magic box? Makes it hard to take them seriously!

Anyway, just to give you a bit more info; I'm setting up a new venture and am starting from scratch - I'm looking for a green way to heat up water for showers (for an absolute max of 16 people) and doing this using a renewable energy is important to us. We were told the upside to the magic box (!) is that we'll easily have hot water 365 days a year.

Shinding

Womble

  • Joined Mar 2009
  • Stirlingshire, Central Scotland
Re: Magic Thermodynamic Box
« Reply #3 on: February 10, 2017, 08:56:06 pm »
Just showers and other hot water, or do you need to do building heating as well?
Experience is what you get just after you needed it.

Shinding

  • Joined Jul 2016
  • West Wales
Re: Magic Thermodynamic Box
« Reply #4 on: February 11, 2017, 10:45:56 am »
Showers & other hot water is a priority. Anything else would be a bonus!
Shinding

chrismahon

  • Joined Dec 2011
  • Gascony, France
Re: Magic Thermodynamic Box
« Reply #5 on: February 12, 2017, 10:43:06 am »
I was told many years ago to divide sales claims by 10 to get a realistic figure. That formula has worked well Womble.


The CoP depends on the difference between the temperature input and output. With high temperature output and low input the CoP may be as low as 2, so taking into account capital costs and maintenance an immersion heater may be far cheaper. Worth remembering that stored water must be taken above 60C to avoid potentially deadly Legionella. So if the system isn't outputting water at that temperature you would need a hot water storage cylinder with extra heating capability.

Womble

  • Joined Mar 2009
  • Stirlingshire, Central Scotland
Re: Magic Thermodynamic Box
« Reply #6 on: February 12, 2017, 10:57:46 am »
Shindig, The concern I'd have with this system is that heat pumps need to run 24/7 for best performance, whereas your demands are really "peaky" (everybody is going to want their shower at roughly the same time in the morning). So to smooth out the peaks, you're going to need a really big tank of hot water somewhere. That costs both money and space. Also, as Chris points out, the tank has to be heated above 60 degC periodically to prevent legionella. If you have to do that with a secondary heater, that's going to firstly ruin the efficiency of the magic box, and secondly add to your costs.


Think very carefully about where you draw your 'system boundary' for renewables. You say that using a renewable energy is important, and that's fair enough. The magic box runs on electricity, so in reality, it's as renewable (or not) as your electricity supply. All it's doing is taking that electricity and "magnifying" it so that you get (maybe) 3.5 times more heat energy out than you put electricity in.


On that analysis, the "Best Possible Environmental Option" might well be to install standard electric showers to heat the water exactly when your guests need it, but use a green electricity tariff to do so. Another option might be a pellet boiler, which naturally provides higher output temperatures, and would also do space heating. These might not seem so 'green' on the face of it, but do you see what I mean about system boundaries?  In eco terms, the only true system boundary we have is the whole planet, so focusing on the building alone is often the wrong approach.
Experience is what you get just after you needed it.

regen

  • Joined Jan 2013
Re: Magic Thermodynamic Box
« Reply #7 on: February 12, 2017, 05:22:40 pm »
One shower and one hot sink then a couple of heat at point of use electric heaters is probably the cheapest option -certainly for capital and installation cost. However if several showers/hot water points could be in use simultaneously then your electricity supply may not cope and the only real answer is a gas or oil fired boiler heating a largish cylinder. This could be complemented by either PV direct or via an immersion type device which would heat the water during the days when the sun shines thro an ordinary immersion element. PV can supply upto 1200kwh per kw installed but most of it is during the spring/summer and take the cylinder up to about 90degs C requiring mixing valves in the system. Alternatively if space is limited then solar thermal panels can be used but these only produce hot water.

The system you describe will indeed produces hot water 24/365 but the 64000 dollar question is how much metered electric it will use- A lot more than a £100 worth I suspect.

Regen

cloddopper

  • Joined Jun 2013
  • South Wales .Carmarthenshire. SA18
Re: Magic Thermodynamic Box
« Reply #8 on: February 13, 2017, 07:36:25 pm »
I've recently seen a weekend retreat / lodge that can bed 18 folk .
Outside was a few inches of snow , a bitingly cold wind , inside I had to take my jacket & jumpers off ,
 I was in croc's , jeans & Tee shirt it was that warm.
It had a heat exchanger for the AC system & recycled the heated dry air back in the building  .

A big ground source heat pump was used to get heat out of the spring that rises 20 mtrs from the building . I was amazed at the massive hot water reservoir tank in the lobby area 2500 litres apparently  again with a massive amount of insulation . There was also a wind turbine   that charged a big bank of batteries & pushed surplus energy into  immersun heaters in the reservoir.

It hadn't long been  commissioned , I'd love to go back there & meet the designers & owners in a years time just to be nosy & find out the financial figures  .
Strong belief , triggers the mind to find the way ... Dyslexia just makes it that bit more amusing & interesting

Shinding

  • Joined Jul 2016
  • West Wales
Re: Magic Thermodynamic Box
« Reply #9 on: February 17, 2017, 02:36:25 pm »
Thanks for all your thoughts/advice so far;

In respect of the electric running costs, I've just spoken to the company who'd be fitting the thermodynamic box, and if we went ahead with it, and they said the costs would be for a 300watt pump which would ramp up to 600w for an hour a day to get the water temp from 55 up to 60 degrees to avoid legionella. Unsure if this actually equates to "less than £100 a year electricity costs" so I'll have to do my homework!!

We could have PV for our domestic use and use that to help with, some, other running costs for the business and bringing the water temp up for an hour a day. And yes, Womble we would need a really large tank, very well insulated.

We're aiming to be a year-round business and will be providing 3 showers and several sinks for a max of 14/16 people with peak demand most probably in the morns & eves. Contractor says that we just won't be able to do that with PV or solar thermal.

I can see what you're saying Womble about looking at system boundaries and the best possible enviro option and it has given me more food for thought.
Shinding

regen

  • Joined Jan 2013
Re: Magic Thermodynamic Box
« Reply #10 on: February 17, 2017, 05:13:40 pm »
"In respect of the electric running costs, I've just spoken to the company who'd be fitting the thermodynamic box, and if we went ahead with it, and they said the costs would be for a 300watt pump which would ramp up to 600w for an hour a day to get the water temp from 55 up to 60 degrees to avoid legionella. Unsure if this actually equates to "less than £100 a year electricity costs" so I'll have to do my homework!!"

300watts x 24 hrs = 7.2kwh +300w+ 7.5kwh per day x365=2700kwh at 15p=£405 pa assuming pump runs continuously and there are no other inputs associated with the installation.- more than i use to run a 4 bed farmhouse at 800ft in wet west wales!

Even if the above is not correct there is no way that this machine will provide all the hot water required for £100 pa with just an air source heat pump assisted by some thermal solar. It is a chocolate teapot!

Regen

pgkevet

  • Joined Jul 2011
Re: Magic Thermodynamic Box
« Reply #11 on: February 19, 2017, 11:12:33 am »
Google it. The website I found implies that the system plugs into the main water tank as an additional loop and recirculates within itself until water reaches 55degs (and it doesn't clearly state C or F) and then goes to standby - so not on 24/7. the example also uses a 200G tank and their illustration reckons about 1KW per day for a tankful. A 5min powershower is 20 gallons so theoretically you can get 10+ showers out of it.. although practicalitiies are that as soon as you pull some hot out of the tank - in goes cold and the system will start up again.

I guess it comes down to how much it costs to install for the experiment 'cos theoretically you could try and mix and match with timers so you heat to 55degs then top up with an immersion. Allowing a mix of folk wanting showers am and or pm you might well get away with a 400gall tank for their hot water needs (unless there's loads of laundry going on ). It might even work out clever to have 2 tanks and a valve system to use one before the other. It'd work out better in a  simple small domestic situation where folk manually manage the use of immersion heaters

cloddopper

  • Joined Jun 2013
  • South Wales .Carmarthenshire. SA18
Re: Magic Thermodynamic Box
« Reply #12 on: February 20, 2017, 01:33:11 am »
Shinding,
I'm developing memory problems these days ( can't even thing of the word for itat present  but the brains starts to lose mass ). So giving you exact details is nigh impossible .

In hope this helps you ...
Can I suggest you look on the Welsh tourist board for a place that can bed 16 or so folks  North / North west of Carmarthen ....say within 20 miles .
It's the place I mentioned in my last post, the accommodation building is white with a slate roof runs roughly North to South with a farm house about 50 meters away to the south end . Coming off the main  road going north to it  is a righttrurn that almost bends back on itself  . goes up a few meters incline , then east then up 60 or so more metres to turn left into th yard area in front of the building .

 If you find such a place sent a \PM with info  & I'll look at their website pictures ... for they are still here in my head to confirm you have the right place  . ( I will will also be able to look at Google earth for it ).

 If you can find it  , it might be worth while to go & see the people & see their  amazing set up .

 
Strong belief , triggers the mind to find the way ... Dyslexia just makes it that bit more amusing & interesting

Shinding

  • Joined Jul 2016
  • West Wales
Re: Magic Thermodynamic Box
« Reply #13 on: February 21, 2017, 02:01:56 pm »
Hi Cloddopper, I have PM'd you with 2 possible names for the place outside Carmarthen you mentioned.

Shinding

Shinding

  • Joined Jul 2016
  • West Wales
Re: Magic Thermodynamic Box
« Reply #14 on: February 21, 2017, 04:57:02 pm »
Thought I'd share this with you: we've been quoted for 2 thermo boxes (1 for a standalone structure: 130L hot water store and 1 for a 2 shower, shower block: 305L store) and the total cost for those (plus installation of sanitary ware) is £9750 plus VAT). This doesn't inc PV system. Elec calcs for both systems are now £420 per annum.

BTW Regen; thank you for your calcs in your last post. Hard to know where to start when one knows absolutely nothing in this field!! Funnily enough, we are based in wet West Wales, though it's been a fairly dry where we are since we got here in Aug.

Thank you too pgkevet for the extra info you found on the company website. I feel as if I'm stumbling around in the dark. We realise we will prob have to pay more for, some, sort of green energy (since the FIT dropped so much) but don't want it to be a ridiculous amount more.
Shinding

 

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