solar panels with thermal store

[qikker]

I have jsut installed a pair of Grant solar panels connected to a Gledhill Torrent SE thermal store, i seems to work very well. I intent to fit a small exhaust air heat pump (air to water) and connect that to the torrent. I was also intending to install a wood burner with boiler to replace my open fire (room heat only) but have decided to fit an esse 350 room heater stove without a boiler and allow the heat pump to reuse some of the generated heat. Hopefull that will make my oil boiler almost redundant.
I am a renewables installer and feel that this system will work well in my 25 year old house. The biggest problem with the thermal store is how to run it in the winter in a way which best utilises any solar energy as I normally run my heating 24hs through a programable room stat which will mean that the store will be required to be up to full working temperature a lot of the time.

There is a pipe stat on the solar circuit to hold off the boiler which may help a little. I'm also going to be installing a grant weather compensating mixer to the heating next week.

I've fitted plenty of solar installations and don't actually see the point of drainback systems a twin coil cylinder and a sealed solar circuit is a clean and simple method preferred by all the major manufacturers.

Just realised I've rambled on about myself in someone elses post, sorry

 

[Norcon]

Evacuated tubes with what looks like a drain back system ?

Drainback will not prevent the panel from reaching very high temperatures (200C+) which if done regularly would shorten the lifespan.

The Navitron evacuated tubes (to take an example) are 'cooled' by the water flow in the manifold. Allowing them to heat up to temperatures in excess of 100 deg C and then blasting them with relatively cold water will result in thermal shock !.
For long-term reliability this would not be good.
Don't know what make PB's panels are but the Navitron evacuated tube manifold contains a thermal sensor to detect the tube (heat-pipe) temperature and control the solar pump - the heat being conducted via the water in the manifold.
Take away the water and there is no means to detect the heat-pipe temperatures

The drain-back principle is used in some flat plate collector systems where the mass of the plate absorbs the heat and the temperature can be sensed direct from the plate surface.

The stated advantage is that antifreeze is not required because - in theory - the water drains out of the collector panel when the pump shuts off and therefore it should not freeze at night...
For what it's worth - it's not a method I would want to utilise on this design of evacuted tubes.

But !.
Your tubes may be different. And indeed your design !.

 

[Paul Barker]

who is using drainback?

Thanks for further useful ideas Bigburner.

i would have prefered to use a combi ala Alpha but i have a buderus regular boiler which i can't sell as it is fire damaged but should be fine after i rewire it. Certainly economically repaireable.

A very green boiler since it is such a good design with respect to long term repairability.

I really do believe with this type system the combi is the perfect partner.

Good to hear from someone who fits these things for a living.
i am partly gathering intellectual capital in case I manage to carve a place in the market. one always has to keep an eye out for work. Stillwaiting for an actual start date with BG if they don't hurry i'll not even start. Aparently it's now iminent. Whether i will last is no small matter.

Plumbers mates in this town are geting laid off. My Napit inspection the guy said he is experiencing no difficulty seeing electricians they are sat at home.

Building trades in diar state.

 

[MartinNormanton]

Hi Paul. You wrote " two 1,000 litre stores arriving Food grade containers £145 the pair delivered." How/where did you find the containers?
I am thinking along your lines, but need container(s) which will fit through the door.

 

[kevindgas]

Hi Paul. You wrote " two 1,000 litre stores arriving Food grade containers £145 the pair delivered." How/where did you find the containers?
I am thinking along your lines, but need container(s) which will fit through the door.

you might notice that he said that over 2 years ago!!