Hot water from PV

[steptoe]

I tend to agree

https://www.electoral-reform.org.uk...have-looked-with-proportional-representation/
But Turkeys will NEVER vote for Xmas

That's not quite right tho as norn iron actually use the PR system, as have for as long as I can remember, so I don't know how they change numbers,
As for the remainder of the UK , it certainly looks like it would be more representative

 

[rugbyguy1]

As a side thought..
and I may be barking up the wrong tree here...

But many years ago I did a rewire for a property that also had a solar-water system fitted..
i.e. some panels consisting of pipes filled with an anti-freeze solution, that was pumped around a coil inside a hot water cylinder with dual coils..
One from solar, on from boiler..

Just made me think what are the advantages / disadvantages between electric and water solar for heating your domestic water supply?

I have Solar Hot Water ! Fantastic. Using Elect to heat Hot Water is expensive. My 1 Solar panel gets water up to 65% in a couple of hrs. Thats been going for some 17yrs, now have to replace pump, not a big job. Rgds.

 

[Berserkerboy]

Depends on how many tubes you have fitted. I put 10 on our last property and was very happy with the results. It's actually more efficient than using PV. However, the coil used in the tank is generally the bottom one, so the whole tank gets heated, which can take a while. Whereas, with PV, your immersion is probably higher up the tank, mine is now at the top. So I'm finding water is up to hot much quicker. There are pro's and cons.

 

[fourtytwo]

I use PV to heat water with a DIY direct converter so the hot water has priority over anything else.
As @Berserkerboy says you don't get a full tank as the immersion tends to be in the top only (I don't know how long my element is but the thermostat is 11").
The reason I went that way instead of PV-water was cost and simplicity, I could use the existing hot water cylinder and there were no pumps etc required.
Also having done my own roof PV install that was hard enough, I certainly would not fancy wielding larger & heavier ? water tubes etc up there!

 

[Gian]

Has anyone heard of a Bunsen air heating system or even installed one.

 

[Berserkerboy]

Just had a quick google. Looks like air source heat pump technology with fewer moving parts. I'd be interested to know the cost of installing one and whether they have a DIY option. I also wonder what the efficiency is bearing in mind some woeful reports on real-world heat pump experiences.
My first thoughts are that it would only be worth doing if you don't have PV. A solic immersion diverter only costs £200 and is extremely efficient.
Although not a direct comparison, as it would work in poor weather conditions, albeit using electric power, it would be up against thermal tubes.
However, a clever bit of technology.

 

[w0z]

Taking the original question down to bare bones
The optimum is to use as little import energy as possible, if you regularly have an excess it makes sense to use as much as you can before export. If you can't use it any other way then long term fitting a cylinder depending on cost, would ensure you always use the excess.
If you can use it to charge an EV or for heat top up the equation changes (fitting an electric heater is a lot cheaper than a cylinder but then that would only cover you for the colder months)
The extra benefit if they get the plumbing right is instant hot water rather than the usual combi delay (awful in my place because it's a long way from the taps)