"Vortex" wrote in message
...
Hi,

Later this year I will be installing a
heatbank (see www.heatweb.com if you
don't know what I'm on about) in my home.
It will replace my indirect hot
water cylinder.

Good choice.

I also intend to have a "secondary solar
loop" in the heatbank so I can
experiment with solar panels....because I
have a south facing pitch on my
roof I reckon I can potentially enjoy solar hot
water - most of the time - for half the year.

I want to understand the practicality and
costs associated with using
"vacuum heat collecting tube" based solar
panels. (This web site says a lot
more http://www.consolchinese.com/old/english/sun01.htm ).

These are expensive. Simple flat plate are a lot cheaper. You can make
them yourself. CAT at http;//www.cat.org.uk, sell a flat plate kit and
instructions.

How about making all the roof a collector. Then you will have a plenty of
hot water delivered. If you have a large roof a lot of flat plates can
return more hot water than a few vacuum tube panels.

Despite extensive Googling I have not been
able to find objective technical
and pricing information for self-install solar
panels in the UK.

I have numerous questions such as:

* What is the typical heat output/square metre in various weather
conditions.
* Is it normal to use pressurised operation (as in unvented CH)?

Can be open vented. Many have self draining panels, that drain into a small
tank when there is no sun.

* What happens if things overheat? I don't think I want my heatbank to
boil.

You have high temp cuts offs that switch off the pump. The heat bank will
its own safety devices anyway, if the panel safety devices fail.

* Do these things deliver usable energy on sunny Winter days?

All energy is usable and its is for nothing. On winters days the temperature
received are low.

* What should I expect to pay?
Any pointers? Any recommendations? Anyone done this?

BTW I've already calculated that I'm unlikely to get payback (ie fuel
savings paying for my efforts) in a realistic timeframe. This is actually
an excercise in self-gratification....and me doing my little bit towards
the
Kyoto climate change treaty.

If the CH is run from the heat bank, the panels will supplement the CH also
in winter. A full south facing roof can provide enough heat in winter to
run low temperature underfloor heating for much of the time. They are an
ideal match.