Can someone please advise regarding using solar panels to drive an immersion heater in a hot water tank? Tank only 30 (possibly 50) litre capacity and mains electricity backup. Yes, mains would be used for maybe 4 months a year, but the other months ought to be ok using mainly solar. Any technical problems regarding the electricity input from the solars, which would be low-current relative to mains?
Why go to the trouble of using PV solar? Surely cheaper and as effective to use solar chauffage made for the job and much easier to install. Works for me.
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Hi Adam1. Been there, done that at previous house, with coiled tank. Was good. BUT here I want no extra plumbing - too difficult. Running a wire from the panels through a microinverter to the immersion is simple. Also no freeze-ups, leaks âŠ
Totally doable. How effective it is will depend on your location & how much PV capacity you can install.
Our 150 litre chauffe eau gains power from PV generation all year round. In the summer, unless we have guests, we never use any mains to heat hot water. Even in the depths of winter we get some contribution on sunny days.
There is another thread about related matters, & the subject of using surplus PV power to drive things.
Any such system will be better off using the PV across your entire supply, with the chauffe eau only using solar when you have a surplus.
Just to reinforce what @Badger says, having separate solar for the immersion heater is not the way to go. You need to integrate the solar into the grid and use a solar diverter for maximum flexibility. All discussed in the other thread.
I had read the other thread, but I donât want to get involved with joining into the grid. My water heating requirements are small (washing up, bathroom, 2 people) so I would just get near to 1kW-worth of solar. I can get four 200W panels for under âŹ600 including the inverter. I can wire it.
Up to 3kWc you can literally plug the system into a socket - no âgetting involvedâ if you donât want to.
Which will only ever be contribution to the needs of the water heater, so you need the grid to make up the difference. If you also fit an energy diverter you can ensure that you only use solar PV to heat the water.
If assuming the output is 500-700watts and in this case the tank is much smaller (50 litres) that would surely surfice (weather permitting)? Even if it takes an extra hour or two.
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Exactly, but the system needs to be grid tied, with a diverter, to make the most sense of this.
Or a Moes ATS,
MOES Dual Power Controller 50A 11000 Watt Automatic Transfer Switch for Off Grid Solar Wind System ATS DC 12V 24V 48V AC 110V 220V Black https://amzn.eu/d/3rnOEY0
Kits Solaires Plug and Play - Branchez et Produisez Ănergie | Materfrance.fr. As an example - itâs probably the lower end of the market but works well enough. You literally plug them in
All the self install suppliers do the kits. Brackets are a bit flimsy but strap them onto a timber frame and problem solved. They will extend the lead (but only in 2.5mm) so your not too limited in placing.
But prices have dropped a lot - There is a glut of panels.
Thanks for those posts. I am looking at: