Heating engineers? Going electric

Solarchaser

As an update to this I have finalised my plans.
I'm ditching the upstairs thermal store.
Instead I'm now going to have 2 x 500L horizontal cylinders with dual coils in them, under the house, specifically under the coldest part of the living room. 
Coil 1 will be for hot water and coil 2 for heating.
Cylinder 1 hot water will daisy chain to cylinder 2, the reason for this is to reduce heat loss, if I have marginal solar I can heat only the second cylinder, so the cold water will go through cylinder 1 with virtually no temperature rise, but then go through cylinder 2 and get hot.
If I have excess solar then cylinder 1 will act as a preheat for cylinder 2.

This should also mean if I have bright days followed by dull days, I should have enough hot water to last last the dull days *should*

Central Heating on the other hand won't work that way, as I'm circulating the same water round a circuit to get hot, dumping it In a cold tank would be a bad idea, instead it will be tee'd into both cylinders, but I will use two port valves attached to cylinder 1 controlled by the water pump, but also a thermal switch, so if its not warm enough to have a positive impact, valve will remain closed and only cylinder 2 will be used to heat the house.
If cylinder 1 is warm enough then the two port valve will open and water will circulate through both cylinders.

I initially wanted to avoid using valves as if they fail I have no heat, but not using them will mean more wasted heat, and a less efficient system... plus I get two free with the cylinders,  so may as well use them 

The 1000L total will mean I have over 40kwh of heat available, which should give me some headroom.

My changes have come from many nights of research and many conversations, including this one, so thanks all for your contributions.👍

The cylinders I will be essentially using the wrong way round, I'll be buying indirect cylinders (so usually heated with a boiler etc) with a second coil (usually used to heat the tank from solar thermal.

The tanks usually work by the coils Providing heat to the water in the tank, I'll be instead heating the water in the tank, with the electfic elements and using the coils to extract the heat.

Hopefully it will work.

I'll find out soon.🤔

Bendy_House

Blimey! Really looking forward to updates on this.

I wouldn't be too concerned about having to use valves as you can be pretty confident they'll give at LEAST 10 years solid service, usually more.

Have you heard the Octopus guy is planning to mass-produce ASHPs and bring their cost down to gas boiler levels?

Solarchaser

No I didn't hear that.
That is good news, octopus really does seem to be an actual ethical company, which is avrare thing in this day and age.

Bendy_House

Yes, he seems a really cool guy.

The 'same as a gas boiler' price will be with the gov's £5k contribution, but still...

Solarchaser

I forgot to update this thread with the link for the green and ethical forum where I've put the project thread,  so here it is

https://forums.moneysavingexpert.com/discussion/6377030/ditching-gas-going-electric-immersion-only-a-wee-project