Do immersun type devices work

[Worcester]

I thought most ppl used GCH like me ??

Not round here! - the majority are on liquid gold aka oil, and turn their boilers off from May - October.

like whats your export rate to grid to work out

Irrelevant when deemed.

 

[danesol]

Not round here! - the majority are on liquid gold aka oil, and turn their boilers off from May - October.

Yes I would agree it would make total sense if had no GAS and were using electric, Oil etc

Irrelevant when deemed.

How can it be irrelevant if you use every last kwh from your Solar array ( ie. use more or less every thing you generate ) - these types of device simply wont return anything then as they wont switch on so I dont understand your comment - explain ??


I'm just doing the calculations now for our household and although we export only 33% of our total generation and use GCH for the primary source to heat the water - there is still some advantage in using one of these types of device but for us it will be along term investment ( looking atm at 8yrs at the cheaper SolarImmersion and far longer for the more expensive Immersun )

However still worth looking at as an add-on and should you get this as a Solar PV package/bundle at the right price your laughing... as i state before every little bit helps

 

[nicksgonesurfin]

Given that is you heat your hot water cylinder with electric, I thought most ppl used GCH like me ??

If you do use GCH - the benefit could be less but still rewarding, again its all about knowing your systems, your needs and whats possible with your system, especially figs



Domestic export is always based on 50export unless you have an import export meter.
Most people do not.

Then your getting paid export plus any savings you make from using more than 50%

@Worcester renewables.

Thanks I didn't know it was a proportional system .

So it will dump what ever is spare into your system?

Good too know.





like whats your export rate to grid to
work out ultimately your ROI !

Thanks for the help see answer in quote above

 

[danesol]

Thanks for the help see answer in quote above

Just not sure what you were trying to tell me then but so we are clear......

Your FITs provider currently give you 50% export payment ( based on your readings ) regardless of what you ACTUALLY provide.

However in reality you could be sending 80% of your total generation to the grid which although you are getting paid for its initial generation, you are ultimately wasting free energy you could utilise...... hence the inclusion of this device to "play the system".

If HOWEVER like me you use the vast majority of your generated electric - there is very little left to use elsewhere and this is what I am suggesting.... the more sauvy PV owner would know this by either monitoring devices or by use of PVO for example

hth

 

[Worcester]

Your PV system is giving you a return over 8 - 10 years which you thought was a good investment - so why isn't an ImmerSun type device when it gives the same return?

- - - Updated - - -

If HOWEVER like me you use the vast majority of your generated electric - there is very little left to use elsewhere and this is what I am suggesting.... the more sauvy PV owner would know this by either monitoring devices or by use of PVO for example

Correct, I agree.

 

[Worcester]

Try using the eco-eye Eco-Eye | Real Time Electricity Monitors | UK - it has an RF device and you can link it up through your pc via cosm (ex pachube) to pvoutput.org (Eco-Eye | Real Time Electricity Monitors | Eco-Eye with Microgeneration/Photovoltaic Installations Eco-Eye | Real Time Electricity Monitors | Eco-Eye used with your computer)

This one uses that system above and has an ImmerSun installed - you can wee how it tracks plus when they had breakfast and put the kettle on

 

[danesol]

Your PV system is giving you a return over 8 - 10 years which you thought was a good investment - so why isn't an ImmerSun type device when it gives the same return?

- - - Updated - - -



Correct, I agree.

No I agree, as long as it lasts that long.... however I was merely pointing out that some will gain enormously with one of these devices ( typically PV owner who uses no electric during the day when sun is out ) but others may not gain so much at all ie. me for example and the risk of achieving the return is higher.

 

[Warlord2001c]

Try using the eco-eye Eco-Eye | Real Time Electricity Monitors | UK - it has an RF device and you can link it up through your pc via cosm (ex pachube) to pvoutput.org (Eco-Eye | Real Time Electricity Monitors | Eco-Eye with Microgeneration/Photovoltaic Installations Eco-Eye | Real Time Electricity Monitors | Eco-Eye used with your computer)

This one uses that system above and has an ImmerSun installed - you can wee how it tracks plus when they had breakfast and put the kettle on

View attachment 17982

I recognise my graph when I see it! Worcester fitted my Immersun less than two weeks ago and it has so far pumped over 30kWh into my hot water tank... Not bad at all considering we've seen very little sun since that day. Most days we have returned from work to a tank of hot water and the boiler has spent almost no time on water heating since then. The tank has very good insulation and we've been able to draw a nightly bath for the young man plus morning showers before the Immersun started again for the following day.

The eco eye smartPV is also proving very accurate as I've been verifying these PVoutput figures against the inverter log and SD card storage from the device which is four second samples rather than 5 minute averages that are sent to COSM.

very happy with both Immersun and smartPV. The PV suppliers were pretty good too!

 

[Berneray]

We have installed about 15 immersun units...though most of them since December so its hard to tell how well they are working yet.

We charge £450 to supply and install if its done at the same time as the PV system. £500 if its a retrospective fit.

One small point we have found....None of the monitoring devices work with Immersun.

Wattson do a similar system Optimersion that works with their monitoring system....but we are sticking with the Immerson....(When we can get stock that is)...

 

[Warlord2001c]

One small point we have found....None of the monitoring devices work with Immersun

Do you mean they don't work at all or that they give false readings?
I use the Eco Eye unit and yes it does add the immersun draw to the grid total when running so gives an overstated grid consumption figure.
To be honest though I'm seeing that as a positive for me as when shown on PVOutput I'm getting a very clear indication of where the immersun is working to bring the PV and Grid totals in sync so I see how little of my PV generated power is going to the grid.
The figures for PV Generation are unaffected and accurate and the Grid total is monitored by my Electricity supplier anyway so not a biggy for me.

 

[adamgp]

Plenty of cheap offers on Google to take advantage of regardless of whether you're a trade customer or not.
Shouldn't take more than an hour to wire from the distribution board to an immersion heater. It only needs about 135 watts of excess power before switching I believe and trickling all excess to the heater!

 

[nicksgonesurfin]

I think this brings an interesting challenge to behavior, 100yrs ago we would have bathed (if we actually did bathe) With the fire heated water, possibly after cooking and eating using the fire. mainly in the evening. Going to bed clean.

Perhaps we have to bathe in the evening?!

another idea is to insulate your tank further or design so the losses over night are minimised and all the PV powered heat is maximised and ensure when the last person has had a shower the HW is turned off so no heating except the solar can go into your system.

seems a lot of hassle i know but its a little like stoking the fire to a roaring flame then going off to work. we wouldnt do that. Because we are disconnected from our energy we don't think about our boilers working when we are not there. (some people do, Timers etc!)

 

[adamgp]

Absolutely, and set your gas boiler to kick in the evening after the sun has set or is setting to make up the difference.. at least this is what I do to maximise the PV energy usage.

 

[bommels]

For more than a year I have been running an early DIY immersion controller, with energy logging capability. Attached is a bar graph of the generation in kWh for April 2013 (2.88kWp array).
The logging allows tracking of where the energy goes: yellow indicates export to grid, red means it has been diverted to the immersion heater, and green marks the PV energy that has been used elsewhere in the household. The system has proven to be so effective that we rely on it entirely for domestic hot water in summer. And, as you can see from the plots, there is still room for improvement, as 42% of our solar PV production was pumped into the grid.

Do immersion controllers work? Certainly they do!

 

[BruceB]

Coincidentally, I had an email today from one of my customers I worked with in the early months of this year putting right a solar pv, solar thermal and ashp installation put in by others. He is full of praise for the immersun. He has about 5kW of PV and a 300 litre Gledhill thermal store in the loft.

"...The Immersun unit has diverted 428 Kwh thus far and is the biggest positive of the project. The only slightly off-putting thing is the noise of a monstrous kettle going off above your head in the bedroom. On a sunny day there are 3Kwh going into the immersion, and you do know it. It becomes the sound of money being saved, and you come to love it........."

 

[BruceB]

I also installed a bank of three thermometers showing the top, middle and bottom temperatures of the thermal store. £10 each from Maplins mounted in his sitting room. Just extended the sensor cables with cat5e. Cheap, cherful and effective. 3-in-1 Digital Probe Clock Thermometer : Thermometers & Hygrometers : Maplin Electronics

".......The three temp gauges in the tv room are the most cost effective part of the deal; we now know exactly what we are dealing with and how effective the wood burner is at a quick burst of heat in the evening; superb."

 

[danesol]

For more than a year I have been running an early DIY immersion controller, with energy logging capability. Attached is a bar graph of the generation in kWh for April 2013 (2.88kWp array).
The logging allows tracking of where the energy goes: yellow indicates export to grid, red means it has been diverted to the immersion heater, and green marks the PV energy that has been used elsewhere in the household. The system has proven to be so effective that we rely on it entirely for domestic hot water in summer. And, as you can see from the plots, there is still room for improvement, as 42% of our solar PV production was pumped into the grid.

Do immersion controllers work? Certainly they do!

View attachment 19012

How many CT sensors have you got fitted to get that level of info and what make are they - do you have a central monitor too ??

 

[bommels]

Hi Danesol,
My setup uses 2 clamps. One clamp sits around the tail at the consumption meter, measuring net import/export, the other clamp sits around the tails leading to the PV system.
Earlier, I have verified that the actual power going into the immersion heater corresponds to what the system thinks is going in there, so I do not have to use a clamp for that.

The clamps were recuperated from the scrap heap and have custom resistors fitted to limit the amplitude/range. Presumably the usual clamps would work just as well. I have not been chasing sub-1% accuracy I must admit.

 

[apj]

I'm considering PV, with flat roof garage could get 6kw system.
heating system is oil, so in addition to immersion i was considering some additional wall mounted rads with heating element direct from PV, can the immersun divert to more than one outlet or would multiple units be needed?
BruceB, graph is a very good idea, a couple of very low generation days - were these much more frequent over winter??

 

[danesol]

I'm considering PV, with flat roof garage could get 6kw system.
heating system is oil, so in addition to immersion i was considering some additional wall mounted rads with heating element direct from PV, can the immersun divert to more than one outlet or would multiple units be needed?
BruceB, graph is a very good idea, a couple of very low generation days - were these much more frequent over winter??

Would it even be worth it going over the domestic threshold of 4KW, considering for a moment rates change commencing Aug 2013 and the reduction in tariff going over 4kw ??

The immersion question is possibly secondary to this ?

All I would say is do the numbers very carefully - I assume you will stay in the building for the next 20yrs too !!!

 

[apj]

Would it even be worth it going over the domestic threshold of 4KW, considering for a moment rates change commencing Aug 2013 and the reduction in tariff going over 4kw ??

The immersion question is possibly secondary to this ?

All I would say is do the numbers very carefully - I assume you will stay in the building for the next 20yrs too !!!

Well the reduction over 4kw is not so much now, so will see. I've already got plenty of numbers to crunch just trying to compare the quotes, there's just a ridiculous difference between some of the quotes with nothing seeming to be true like for like, with everyone either claiming their panels are 'so much better than others on the market' or that there 'really isn't much difference between them all'!!