Solar Panel immersion heater automatic switch.

[solarfred]

Here is a fully compliant system running 9 (yes 9) immersion heaters only using PV power. 3 phase system with house on one phase (so EMMA was not going to work). The power is from 27kw array and heating 3000 litre store for swimming pool and then surplus into house DHW. Not one for the purists but it was a project I had to accept.
The pool house is 70 metres from the inverters and the CT clamps measuring all three phases for PV and house loads. The system runs via RF to the sockets.
We have it running but are now fine tuning. I have got them to install 3 x 1.5kw elements in the first switches so as to get it working virtually all the time with the rest 3kw elements.
We can set the time of operation per day/ the time delay of switching from 0 minutes upwards (to allow for brief interruptions) / balance of power switching point in watts. Stepped switching so as power changes the immersions switch on or off to keep it all positive.
Key is getting the programme correct so as to minimise the export potential. As customer is getting paid for production and deemed export so a little bit of export is allowable! Import is a no, no.

 

[thushar]

One can consult illumilitr[dot]com[dot]au they have expertise and can give consultancy. I do not know about electrical.

The same product and much more advanced version is now available at Intelligent Solar PV Immersion Heater Switch - Use Surplus PV Power to Heat Water. The latest version Mark II monitors both PV production and in-house consumption just with a single sensor! Rumours are a Mark III version with proportional controller will be out soon .

 

[Worcester]

Why wait, Immmersun already does it fully proportional and more:, cascade, additonal boiler / timer (see legionella) Plus more yet to come ...

 

[thushar]

Why wait, Immmersun already does it fully proportional and more:, cascade, additonal boiler / timer (see legionella) Plus more yet to come ...

It may worth the wait for a week or so, as immersun is around £600 while the proportional controller from Intelligent Solar PV Immersion Heater Switch - Use Surplus PV Power to Heat Water will be below £300

 

[Gavin A]

It may worth the wait for a week or so, as immersun is around £600 while the proportional controller from Intelligent Solar PV Immersion Heater Switch - Use Surplus PV Power to Heat Water will be below £300

not really. We're offering Immersun fully installed for £499, significantly less if installed at the same time as a solar PV installation, and/or voltage optimiser.

I believe this is around the going rate as well.

 

[audreyhudges]

I agree also that it is quite expensive but as I since electrical knowledge is needed making on your own is really in need. If you want to save more then solar panel could really help you.

 

[SolarCity]

Gavin, I was just reading your link on your website - you mention that this could also be used to divert power to the dishwasher or washing machine. Can it really work that way? Surely as soon as the washing machine starts, you need it to complete the whole cycle? What am I missing?

 

[yellowvanman]

The Immersun only works on a resitive load, anything with motors/electronic controllers will not work, may even damage them, so washing machines/dishwashers are not suitable - and generally they are plugged into the ring main.

Resistive loads include immersions and storage heaters (as long as these don't have a fan) and should be on their own dedicated circuit.

 

[jason121]

immersun have volt free contacts

 

[SolarCity]

immersun have volt free contacts

To operate on a certain generation point and for a certain amount of time?

 

[yellowvanman]

immersun have volt free contacts

Can you explain further that comment?

 

[Worcester]

Download the user manual and wiring diagrams from here : Technical Resources | Micro-Generation Power Manager

 

[jason121]

its in the manual additional loads if over 3kw use seperate contactor but will not be PI controlled
if PI controlled only use resistive loads

 

[Worcester]

As well as the standard proportional output functions, it can also be daisy chained for higher output (or consuming) systems, the proprtional output can be 'rolled' over to a second resistive load if the immersion is up to temperature, it has a built in relay that can be controlled by various functions and features to control any load that you like, resistive or inductive.

How you can use and configure the controller is really down to your imagination - that relay for example can be used to trigger the normal boiler (you next least cost heating option of your choice) to come on at the end of the day to ensure that the hot water is up to temperature say during winterm, or on an overclouded rainy sunny day (like today for us)

In our case (oil) we use the timer to to trigger the immersion on at 7:30pm for an hour, if it doesn't need it, eben though it's on. the immersion of course won't draw the power ..

Imagination is more important than knowledge (Einstein)

 

[yellowvanman]

How you can use and configure the controller is really down to your imagination - that relay for example can be used to trigger the normal boiler (you next least cost heating option of your choice) to come on at the end of the day to ensure that the hot water is up to temperature say during winterm, or on an overclouded rainy sunny day (like today for us)

I can see what you're saying but wouldn't it be easier to just have your oil boiler programmed as normal, if the tank temp is low then the tank stat will call for heat from the boiler anyway.

 

[yellowvanman]

Worcester
I've had a look at your link and some of your news articles, can you explain fiurther on the following:

'so once the water is hot, it will then send the excess power to a storage radiator, whilst still constantly monitoring the immersion to ensure a full tank of hot water'

How does it monitor the immersion in such a way?

 

[Worcester]

Aha, it knows if it is drawing power on not - it also monitors when trying to send power to the proportionally controlled circuit wether any is going there, if it isn't it will then send it to the second load, and then every minute go back and check to see if the immersion needs it - so if the immersion (or primary load doesn;t need it) it could either send a proportionally controlled power to another resitive load, or switch on a de-stratification pump, then send the power back to the immersion when it is ready.


Simples as Sergei would say

 

[Worcester]

I can see what you're saying but wouldn't it be easier to just have your oil boiler programmed as normal, if the tank temp is low then the tank stat will call for heat from the boiler anyway.

Yes that would work fine as well.

 

[Glynn Fletcher]

Hello Everyone, new to the forum,my first post.
I have recently had a 4kw PV array fitted to my roof and want some kind of immersion heater switch to use up the "spare" power rather than let it go back, unpaid for, to the grid. I have read about various ones that use 1 and 1.5 Kw immersion heaters but a recent one called SolarImmersion (mark 3) seems far superior. This lets you keep the 3Kw immersion heater and diverts ALL the unused power. Does anyone have one fitted or know anything about them, they are £250 which seems a lot but compared with the PV array on the roof it seems quite cheap. Thanks for reading.
Glynn.

 

[Trader9]

Hi Glynn

Welcome to the forum. I have built my own diverter and you can to for less than £100. Last year I diverted more than 1MWh into my 3kW immersion heater. Go to the Talking Solar web site for construction details and links to the OpenEnergyMoniter site where the system came from. Only a handfull of components are required and PCB's are available.

Regards, Trader9.