Need help & advice on solar electricity/heating - confused!!!

[RandomMess]

So we are buying a property to which we will be doing extensive remodelling and has a very old boiler and cylindar tank.

We are looking at installing solar electricity/heating - errr something!
DH works from home (computer based)
I work part time so can do lots of domestic stuff during the day
We have 4 dc aged 9 & up

I would say we are quite heavy electricity users!

My questions...
Is it possible to just have the electricity creating stuff that somehow heats hot water or stores heating somehow to be used in the evening - or is using stored warm water from the heating panels the only option?

We will have a 3 story house would it be worth installing underfloor heating at the basement/ground floor level - we are starting from scratch down there.

Can you still be demanding during the day more electricity than you are creating? How do you work out how much electricty you demand?

I have looked at various websites and am still rather confused.

Not quite sure I understand your question: are you thinking of having solar PVs installed (i.e. the ones that generate electricity)? In that case you could consider installing en Ecocent or something similar. You can set it to run at the times you are producing maximum electricity and it will store hot water for the rest of the time. Alternatively you have thermal panels, which will heat up the water when the sun shines and store it. When there isn't sufficient light/heat you then back up with an immersion heater.

If you have PV's they will be linked up to the mains: if you produce more than you use, surplus will be exported. If you produce less than you use, you buy back electricity as normal.

Thanks oricella that does help. I will go look up what an Ecocent is!!!

I'm even more confused now

I want to know from an independent source (ie not a company trying to sell me something) what is the best option for us!!!

We get solar electricity panels.

We can in part use the electricity to part heat hot water in a storage tank.

Can we then use some sort of gas boiler to heat the water to the correct temperature for
a) hot water
b) central heating

Is there a mechanism so when you aren't producing spare electricity it stops heating up the hot water tank?

Sorry I am being very thick but I'm still just going around in circles. As far as I can tell you don't get to sell back your spare electricity anymore so it's about using what you are producing to it's full capacity

It's a steep learning curve..

As far as I understand the FIT rates cover for what you produce (even if you don't use it): the export rate was always marginal compared to the actual production rates. So yes, best would be to maximize electricity use during the day - but I wouldn't get too hung up on not using it all to the max.

As far as I know there isn't a mechanism to tie in the heater to solar PV output. What works for us is to set the hot water to come on for 3 hours in the afternoon when on average solar output is highest. The advantage of an ecocent is that it runs at a low wattage (600 W I think) compared to an immersion heater - so even if there is little sunshine it is cheaper than an immersion heater. POssibly not cheaper than gas though. Efficiency also depends on the lay out of your house: it will work best when you have some passive solar gain. If you have lots of separate rooms you may just be better off with gas heating.

The navitron forums are full of good advice too: best thing would be to read up as much as you can and be really well prepared when you ask a few companies for input. Good luck