Is there such a beast available that combines an electric producing
solar panel with water heating? I'm guessing having a water circuit
carrying the heat from the presumably high temperature solar panels
might serve to pre-heat water before sending it through the boiler or
WHY and increase the life-span of the panel?
Or does the generation/removal of electricity significantly reduce the
temperature of the big flat black surface?

I'm also guessing the installation of solar panels on a roof reduces the
heat transferred into the roof/loft space in the house by a fair amount?

There must be a reason why solar panels don't seem to come with a water
heating circuit?

Just a thought..

--
http://www.GymRatZ.co.uk - Fitness+Gym Equipment.
http://www.water-rower.co.uk

On 24/05/2012 20:50, www.GymRatZ.co.uk wrote:
Is there such a beast available that combines an electric producing
solar panel with water heating?

Edit: Should read Solar PV panels with a water heating circuit (to save
confusion)

Pete
--
http://www.GymRatZ.co.uk - Fitness+Gym Equipment.

On Thu, 24 May 2012 20:50:37 +0100, www.GymRatZ.co.uk wrote:

Is there such a beast available that combines an electric producing
solar panel with water heating?

Yes I saw something about hybrid panels just the other day, trouble
is it was out on the web...

I'm guessing having a water circuit carrying the heat from the
presumably high temperature solar panels might serve to pre-heat water
before sending it through the boiler or WHY and increase the life-span
of the panel?

I didn't pay much attention o the details of the hybrids but I'd
expect the wet side to function much the same as normal solar thermal
system ie some form of thermal store. Of course the solar thermal may
not gather as much energy per unit area as a conventional solar
thermal as it's shaded by the solar PV. But then the solar PV needs
considerably more area than solar thermal to give similar power
levels.

There must be a reason why solar panels don't seem to come with a water
heating circuit?

You don't get 43p/kWhr for solar thermal...

--
Cheers
Dave.

"www.GymRatZ.co.uk" wrote

Is there such a beast available that combines an electric producing
solar panel with water heating? I'm guessing having a water circuit
carrying the heat from the presumably high temperature solar panels
might serve to pre-heat water before sending it through the boiler or
WHY and increase the life-span of the panel?

Or does the generation/removal of electricity significantly
reduce the temperature of the big flat black surface?

Nope.

I'm also guessing the installation of solar panels on a roof reduces the
heat transferred into the roof/loft space in the house by a fair amount?

Yep.

There must be a reason why solar panels don't seem to come with a water
heating circuit?

Yep. What works best for producing electricity isnt suitable for heating
water.

If you just want a crude system to preheat the water for the boiler
etc, whats used to heat swimming pools will work fine and is a lot
cheaper than a fancy engineered system that combines a solar panel
and water heating.

And if you want something that really heats the water
properly to high temps, its better to have two separate
systems, one for the electricity and one for the water.

Just a thought..

I gave up on those, they just make my head hurt.

On 24/05/2012 20:50, www.GymRatZ.co.uk wrote:
Is there such a beast available that combines an electric producing
solar panel with water heating? I'm guessing having a water circuit
carrying the heat from the presumably high temperature solar panels
might serve to pre-heat water before sending it through the boiler or
WHY and increase the life-span of the panel?
Or does the generation/removal of electricity significantly reduce the
temperature of the big flat black surface?

I'd guess it doesn't lose that much and deliberately cooling a solar PV
array improves its efficiency but you are stuck with the problem of the
plumbing and extra weight and it is probably only worth the effort in
mid summer. You would probably want to feed the water through a
concentrating collector to get a decent temperature hot water out.

I'm also guessing the installation of solar panels on a roof reduces the
heat transferred into the roof/loft space in the house by a fair amount?

There must be a reason why solar panels don't seem to come with a water
heating circuit?

Cost and complexity and the mismatch between the area needed for solar
hot water vs solar PV. It is ironic that the subsidised solar PV which
is all the rage has very limited economic return without the daft FIT
scheme whereas the solar hot water which is actually viable in parts of
the UK is severely discouraged by the governments crazy subsidies.

--
Regards,
Martin Brown

On 24/05/2012 21:39, Rod Speed wrote:

And if you want something that really heats the water
properly to high temps, its better to have two separate
systems, one for the electricity and one for the water.

Thanks for input Rod
It all revolves around a proposed extension which will (if given the
go-ahead) give us a 15m long x 2.5m pitched roof with SW elevation.

Given that our house is heated just fine for both UFH and Rad. zones
with max. flow rate of 55 degrees C and we're sort sort of down south
(Bristol latitude) if I could get 55 degrees from such a system for 4
hours of the day in deep winter it _might_ prove to be of significant
benefit by offsetting boiler run/start time into the evening.

Perhaps a summer/winter diverter that could (pre)heat DHW in summer and
CH in winter...

Just found http://www.newformenergy.com/
and bounced them a few questions.

All depends on planning app. at the moment though... (and of course
price of such a hybrid solution)
8¬|

Cheers - Pete
--
http://www.GymRatZ.co.uk - Fitness+Gym Equipment.

On May 24, 8:50*pm, "www.GymRatZ.co.uk"
wrote:
Is there such a beast available that combines an electric producing
solar panel with water heating? I'm guessing having a water circuit
carrying the heat from the presumably high temperature solar panels
might serve to pre-heat water before sending it through the boiler or
WHY and increase the life-span of the panel?
Or does the generation/removal of electricity significantly reduce the
temperature of the big flat black surface?

I'm also guessing the installation of solar panels on a roof reduces the
heat transferred into the roof/loft space in the house by a fair amount?

There must be a reason why solar panels don't seem to come with a water
heating circuit?

Just a thought..

It would give you a large amount of low temp warm water, which is far
from ideal. Also no useful output in spring and autumn,again hardly
ideal. And where any type of sometimes cold collector meets q
sometimes hot panel, you're going to get trapped condensation, which
is not a good thing.


NT

On Thu, 24 May 2012 22:00:04 +0100, www.GymRatZ.co.uk wrote:

if I could get 55 degrees from such a system for 4 hours of the day in
deep winter ...

Well our 30 tube collector occasionally got to that temperature in
the winter but that was about all that got hot. If you tried to
circulate the water to extract the heat there simply wasn't the heat
input to warm the circulating water. A bright sunny day might have
had it running for an hour either side of solar noon. Compare that
with the same wall to wall sunshine we are having ATM. it's starting
up very soon after the sun starts to shine on it (0800-0900) and runs
through until the sun is off it (1700-1800).

it _might_ prove to be of significant benefit by offsetting boiler
run/start time into the evening.

A normal solar thermal system produces at best 2 to 3kW. It'll heat a
thermal store for HW use pretty effectively during a summers day but
that energy is very little when compared to space heating
requirements.

There is no reason why one couldn't install a larger collector but
what do you do with all that heat in the summer when you have no
space heating requiremen?

--
Cheers
Dave.

Dave Liquorice wrote
www.GymRatZ.co.uk wrote

if I could get 55 degrees from such a system
for 4 hours of the day in deep winter ...

Well our 30 tube collector occasionally got to that temperature
in the winter but that was about all that got hot. If you tried to
circulate the water to extract the heat there simply wasn't the heat
input to warm the circulating water. A bright sunny day might have
had it running for an hour either side of solar noon. Compare that
with the same wall to wall sunshine we are having ATM. it's starting
up very soon after the sun starts to shine on it (0800-0900) and runs
through until the sun is off it (1700-1800).

it _might_ prove to be of significant benefit by offsetting boiler
run/start time into the evening.

A normal solar thermal system produces at best 2 to 3kW. It'll heat a
thermal store for HW use pretty effectively during a summers day but
that energy is very little when compared to space heating requirements.

There is no reason why one couldn't install a larger collector but
what do you do with all that heat in the summer when you have no
space heating requiremen?

Just cover part of it would be one obvious approach.

Makes a lot more sense to do a solar air heater tho for winter.

Much easier to do and trivial to just not move the air in summer.

On 24/05/2012 23:05, Dave Liquorice wrote:

There is no reason why one couldn't install a larger collector but
what do you do with all that heat in the summer when you have no
space heating requiremen?

Ah well I was also thinking about that one earlier...
The front garden/drive etc could be used as an Interseasonal Thermal
Store. Dump hrat into the ground through the summer and tap it off
again in the winter.
Front garden is going to be completely re-modeled anyway as drive is to
be moved etc....
:¬)

"www.GymRatZ.co.uk" wrote
Dave Liquorice wrote

There is no reason why one couldn't install a larger
collector but what do you do with all that heat in the
summer when you have no space heating requiremen?

Ah well I was also thinking about that one earlier...
The front garden/drive etc could be used as an Interseasonal
Thermal Store. Dump hrat into the ground through the
summer and tap it off again in the winter.

It just isnt feasible to do that on a house block. Even just enough
heat stored for overnight use from the day before takes quite
literally rooms full of road aggregate with a solar air system.

Front garden is going to be completely re-modeled
anyway as drive is to be moved etc....
:¬)

NT wrote:
On May 24, 8:50 pm, "www.GymRatZ.co.uk"
wrote:
Is there such a beast available that combines an electric producing
solar panel with water heating? I'm guessing having a water circuit
carrying the heat from the presumably high temperature solar panels
might serve to pre-heat water before sending it through the boiler or
WHY and increase the life-span of the panel?
Or does the generation/removal of electricity significantly reduce the
temperature of the big flat black surface?

I'm also guessing the installation of solar panels on a roof reduces the
heat transferred into the roof/loft space in the house by a fair amount?

There must be a reason why solar panels don't seem to come with a water
heating circuit?

Just a thought..

It would give you a large amount of low temp warm water, which is far
from ideal. Also no useful output in spring and autumn,again hardly
ideal. And where any type of sometimes cold collector meets q
sometimes hot panel, you're going to get trapped condensation, which
is not a good thing.


NT

also relevant is the further reduction of FITS

http://www.telegraph.co.uk/finance/personalfinance/consumertips/household-bills/9287863/Government-plans-to-cut-solar-feed-in-tariff.html


--
To people who know nothing, anything is possible.
To people who know too much, it is a sad fact
that they know how little is really possible -
and how hard it is to achieve it.

On May 24, 8:50*pm, "www.GymRatZ.co.uk"
wrote:
Is there such a beast available that combines an electric producing
solar panel with water heating? I'm guessing having a water circuit
carrying the heat from the presumably high temperature solar panels
might serve to pre-heat water before sending it through the boiler or
WHY and increase the life-span of the panel?
Or does the generation/removal of electricity significantly reduce the
temperature of the big flat black surface?

I'm also guessing the installation of solar panels on a roof reduces the
heat transferred into the roof/loft space in the house by a fair amount?

There must be a reason why solar panels don't seem to come with a water
heating circuit?

Just a thought..

--http://www.GymRatZ.co.uk- Fitness+Gym Equipment.http://www.water-rower.co.uk

Such a device would be pointless. Apart from the sun they are
unrelated technologies.
What I have seen is a solar thermal panel with a small PVpanel to
work the water circulating pump.
This is a brilliant idea because as the sunlight intensiifies the (DC)
pump speeds up so keeping a constant temperature output from the
thermal panel.

On May 24, 10:00*pm, "www.GymRatZ.co.uk"
wrote:
On 24/05/2012 21:39, Rod Speed wrote:

And if you want something that really heats the water
properly to high temps, its better to have two separate
systems, one for the electricity and one for the water.

Thanks for input Rod
It all revolves around a proposed extension which will (if given the
go-ahead) give us a 15m long x 2.5m pitched roof with SW elevation.

Given that our house is heated just fine for both UFH and Rad. zones
with max. flow rate of 55 degrees C and we're sort sort of down south
(Bristol latitude) if I could get 55 degrees from such a system for 4
hours of the day in deep winter it _might_ prove to be of significant
benefit by offsetting boiler run/start time into the evening.

Perhaps a summer/winter diverter that could (pre)heat DHW in summer and
CH in winter...

Just foundhttp://www.newformenergy.com/
and bounced them a few questions.

All depends on planning app. at the moment though... (and of course
price of such a hybrid solution)
8¬|

Cheers - Pete
--http://www.GymRatZ.co.uk- Fitness+Gym Equipment.

Such a device is pointless. You don't need any house heating when the
sun is shining. Heat collected in Winter is minimal in the UK climate.
Spend your money on insulation.
Rod is from Oz ergo most of the stuff he rambles on about is
irrelevant here in the UK.
http://www.flickr.com/photos/ara-chl...7627608971673/

On May 25, 12:10*am, "Rod Speed" wrote:
Dave Liquorice wrote





www.GymRatZ.co.ukwrote
if I could get 55 degrees from such a system
for 4 hours of the day in deep winter ...
Well our 30 tube collector occasionally got to that temperature
in the winter but that was about all that got hot. If you tried to
circulate the water to extract the heat there simply wasn't the heat
input to warm the circulating water. A bright sunny day might have
had it running for an hour either side of solar noon. Compare that
with the same wall to wall sunshine we are having ATM. it's starting
up very soon after the sun starts to shine on it (0800-0900) and runs
through until the sun is off it (1700-1800).
it _might_ prove to be of significant benefit by offsetting boiler
run/start time into the evening.
A normal solar thermal system produces at best 2 to 3kW. It'll heat a
thermal store for HW use pretty effectively during a summers day but
that energy is very little when compared to space heating requirements.
There is no reason why one couldn't install a larger collector but
what do you do with all that heat in the summer when you have no
space heating requiremen?

Just cover part of it would be one obvious approach.

Makes a lot more sense to do a solar air heater tho for winter.

Much easier to do and trivial to just not move the air in summer. *- Hide quoted text -

- Show quoted text -

I dunno why you ramble on about a climate you have zero knowledge
about.
You really ought to shut up. Go find some Ozians to annoy.

On May 25, 1:52*am, "Rod Speed" wrote:
"www.GymRatZ.co.uk" wrote

Dave Liquorice wrote
There is no reason why one couldn't install a larger
collector but what do you do with all that heat in the
summer when you have no space heating requiremen?
Ah well I was also thinking about that one earlier...
The front garden/drive etc could be used as an Interseasonal
Thermal Store. *Dump hrat into the ground through the
summer and tap it off again in the winter.

It just isnt feasible to do that on a house block. Even just enough
heat stored for overnight use from the day before takes quite
literally rooms full of road aggregate with a solar air system.



Front garden is going to be completely re-modeled
anyway as drive is to be moved etc....
:¬)- Hide quoted text -

- Show quoted text -

Forget a bout thermal stores. They fail on a small scale and are
vastly expensive.

harry wrote
Rod Speed wrote
Dave Liquorice wrote
www.GymRatZ.co.ukwrote

if I could get 55 degrees from such a system
for 4 hours of the day in deep winter ...

Well our 30 tube collector occasionally got to that temperature
in the winter but that was about all that got hot. If you tried to
circulate the water to extract the heat there simply wasn't the heat
input to warm the circulating water. A bright sunny day might have
had it running for an hour either side of solar noon. Compare that
with the same wall to wall sunshine we are having ATM. it's starting
up very soon after the sun starts to shine on it (0800-0900) and runs
through until the sun is off it (1700-1800).

it _might_ prove to be of significant benefit by offsetting boiler
run/start time into the evening.

A normal solar thermal system produces at best 2 to 3kW. It'll heat a
thermal store for HW use pretty effectively during a summers day but
that energy is very little when compared to space heating requirements.
There is no reason why one couldn't install a larger collector but
what do you do with all that heat in the summer when you have no
space heating requiremen?

Just cover part of it would be one obvious approach.

Makes a lot more sense to do a solar air heater tho for winter.

Much easier to do and trivial to just not move the air in summer.

I dunno why you ramble on about a climate you have zero knowledge about.

Know a hell of a lot more about solar and house
heating than you ever do, you silly senile old fart.

You're so stupid you don't even realise the hybrid systems
are sold in spite of your stupid claim that they are pointless.

reams of your puerile **** any 2 year old could leave for dead flushed
where it belongs

"harry" wrote in message
...
On May 24, 10:00 pm, "www.GymRatZ.co.uk"
wrote:
On 24/05/2012 21:39, Rod Speed wrote:

And if you want something that really heats the water
properly to high temps, its better to have two separate
systems, one for the electricity and one for the water.

Thanks for input Rod
It all revolves around a proposed extension which will (if given the
go-ahead) give us a 15m long x 2.5m pitched roof with SW elevation.

Given that our house is heated just fine for both UFH and Rad. zones
with max. flow rate of 55 degrees C and we're sort sort of down south
(Bristol latitude) if I could get 55 degrees from such a system for 4
hours of the day in deep winter it _might_ prove to be of significant
benefit by offsetting boiler run/start time into the evening.

Perhaps a summer/winter diverter that could (pre)heat DHW in summer and
CH in winter...

Just foundhttp://www.newformenergy.com/
and bounced them a few questions.

All depends on planning app. at the moment though... (and of course
price of such a hybrid solution)
8¬|

Cheers - Pete
--http://www.GymRatZ.co.uk- Fitness+Gym Equipment.

Such a device is pointless. You don't need
any house heating when the sun is shining.

More mindless drivel, most obviously with existing
houses that arent practical to redo as passive solar etc.

Heat collected in Winter is minimal in the UK climate.

Wrong, as always. Passive solar works fine there, fool.

"harry" wrote in message
...
On May 25, 1:52 am, "Rod Speed" wrote:
"www.GymRatZ.co.uk" wrote

Dave Liquorice wrote
There is no reason why one couldn't install a larger
collector but what do you do with all that heat in the
summer when you have no space heating requiremen?
Ah well I was also thinking about that one earlier...
The front garden/drive etc could be used as an Interseasonal
Thermal Store. Dump hrat into the ground through the
summer and tap it off again in the winter.

It just isnt feasible to do that on a house block. Even just enough
heat stored for overnight use from the day before takes quite
literally rooms full of road aggregate with a solar air system.



Front garden is going to be completely re-modeled
anyway as drive is to be moved etc....
:¬)-

Forget a bout thermal stores. They fail on a small scale

Wrong, as always.

and are vastly expensive.

Even sillier. A room full of road aggregate costs
peanuts and if costs peanuts to do a solar air heater

That claim of yours is as stupid as your previous stupid
pig ignorant claim that active solar just isnt feasible.

On Fri, 25 May 2012 01:22:37 +0100, www.GymRatZ.co.uk wrote:

There is no reason why one couldn't install a larger collector but
what do you do with all that heat in the summer when you have no
space heating requiremen?

Ah well I was also thinking about that one earlier...
The front garden/drive etc could be used as an Interseasonal Thermal
Store.

Do the maths. To store a useful amount of heat you will need a big
store and lots of insulation. When planning the system here I did
half look at how big a store would need to be to supply a days heat.
I think it came out at about 1500l of water at 90C. So to store just
a months worth of heat it's getting a bit big...

I know of a system with ground source heat pump and solar thermal. If
the solar thermal gets the store to it's maximum safe temperature it
dumps the any excess heat into the ground but having thought about it
that is just a heat sink the heat won't stay there 'till the winter
to be pumped back out.

--
Cheers
Dave.

On 25/05/2012 08:53, Dave Liquorice wrote:

I know of a system with ground source heat pump and solar thermal. If
the solar thermal gets the store to it's maximum safe temperature it
dumps the any excess heat into the ground but having thought about it
that is just a heat sink the heat won't stay there 'till the winter
to be pumped back out.

I read on t'internet that heat moves very slowly through the ground.
I think it was in the region of 1 metre / month.

So theoretically.... 30M bore holes would swallow up (and retain) a hell
of a lot of dumped solar thermal, might take several summers to reach
max. "working" temp though.

However.... if the heat has to be extracted back via GSHP the finances
of such a project render it completely pointless.

;¬)

--
http://www.GymRatZ.co.uk - Fitness+Gym Equipment.

In article o.uk, Dave Liquorice wrote:

I know of a system with ground source heat pump and solar thermal. If
the solar thermal gets the store to it's maximum safe temperature it
dumps the any excess heat into the ground but having thought about it
that is just a heat sink the heat won't stay there 'till the winter
to be pumped back out.

It can be done, but it's not trivial:
http://en.wikipedia.org/wiki/Seasonal_thermal_store
http://www.icax.co.uk/thermalbank.html

In article o.uk, Dave Liquorice wrote:

There is no reason why one couldn't install a larger collector but
what do you do with all that heat in the summer when you have no
space heating requiremen?

Heat an outdoor swimming pool that isn't used in the winter....

On 25/05/2012 06:42, harry wrote:

Such a device is pointless. You don't need any house heating when the
sun is shining. Heat collected in Winter is minimal in the UK climate.

But if the cooling of the PV increases their output and can provide a
20+ (?) degree temperature rise to pre-heat mains cold water before it
goes through the combi. that could in it's self could make quite a
reduction on gas consumption during summer months for DHW would it not?

(throwing ideas in the air for discussion and dissection)

--
http://www.GymRatZ.co.uk - Fitness+Gym Equipment.

harry wrote:
On May 24, 8:50 pm, "www.GymRatZ.co.uk"
wrote:
Is there such a beast available that combines an electric producing
solar panel with water heating? I'm guessing having a water circuit
carrying the heat from the presumably high temperature solar panels
might serve to pre-heat water before sending it through the boiler or
WHY and increase the life-span of the panel?
Or does the generation/removal of electricity significantly reduce the
temperature of the big flat black surface?

I'm also guessing the installation of solar panels on a roof reduces the
heat transferred into the roof/loft space in the house by a fair amount?

There must be a reason why solar panels don't seem to come with a water
heating circuit?

Just a thought..

--http://www.GymRatZ.co.uk- Fitness+Gym Equipment.http://www.water-rower.co.uk

Such a device would be pointless.

Harry, all renewable energy devices are pointless.

Dave Liquorice wrote:
On Fri, 25 May 2012 01:22:37 +0100, www.GymRatZ.co.uk wrote:

There is no reason why one couldn't install a larger collector but
what do you do with all that heat in the summer when you have no
space heating requiremen?
Ah well I was also thinking about that one earlier...
The front garden/drive etc could be used as an Interseasonal Thermal
Store.

Do the maths. To store a useful amount of heat you will need a big
store and lots of insulation. When planning the system here I did
half look at how big a store would need to be to supply a days heat.
I think it came out at about 1500l of water at 90C. So to store just
a months worth of heat it's getting a bit big...

I know of a system with ground source heat pump and solar thermal. If
the solar thermal gets the store to it's maximum safe temperature it
dumps the any excess heat into the ground but having thought about it
that is just a heat sink the heat won't stay there 'till the winter
to be pumped back out.

It actually can.

That's how heat pumps work - summer heat is stored in the ground over
winter.



--
To people who know nothing, anything is possible.
To people who know too much, it is a sad fact
that they know how little is really possible -
and how hard it is to achieve it.

On 25/05/2012 09:45, www.GymRatZ.co.uk wrote:
On 25/05/2012 06:42, harry wrote:

Such a device is pointless. You don't need any house heating when the
sun is shining. Heat collected in Winter is minimal in the UK climate.

But if the cooling of the PV increases their output and can provide a
20+ (?) degree temperature rise to pre-heat mains cold water before it
goes through the combi. that could in it's self could make quite a
reduction on gas consumption during summer months for DHW would it not?

(throwing ideas in the air for discussion and dissection)

The problem is one of cost effectiveness and complexity.

There is no point in saving power usage to create vast quantities of
lukewarm water that you don't need in mid-summer if it makes the whole
installation a lot more expensive and prone to failure.

A rough rule of thumb is that summer DHW is less than 10% maybe as low
as 5% of peak winter space heating requirements. We are just too far
north for solar power to be sensible without market distorting FITs.

--
Regards,
Martin Brown

Martin Brown wrote:
On 25/05/2012 09:45, www.GymRatZ.co.uk wrote:
On 25/05/2012 06:42, harry wrote:

Such a device is pointless. You don't need any house heating when the
sun is shining. Heat collected in Winter is minimal in the UK climate.

But if the cooling of the PV increases their output and can provide a
20+ (?) degree temperature rise to pre-heat mains cold water before it
goes through the combi. that could in it's self could make quite a
reduction on gas consumption during summer months for DHW would it not?

(throwing ideas in the air for discussion and dissection)

The problem is one of cost effectiveness and complexity.

There is no point in saving power usage to create vast quantities of
lukewarm water that you don't need in mid-summer if it makes the whole
installation a lot more expensive and prone to failure.

A rough rule of thumb is that summer DHW is less than 10% maybe as low
as 5% of peak winter space heating requirements. We are just too far
north for solar power to be sensible without market distorting FITs.


I calculated that my annual DHW costs are about £100 quid. My annual
heating costs are now getting on for £2000 of which about £1200 is
between November and March. Plus a couple of hundred for wood.

That's on a fully insulated house run as cold as I dare.


--
To people who know nothing, anything is possible.
To people who know too much, it is a sad fact
that they know how little is really possible -
and how hard it is to achieve it.

On 25/05/2012 10:02, The Natural Philosopher wrote:
Martin Brown wrote:

The problem is one of cost effectiveness and complexity.

There is no point in saving power usage to create vast quantities of
lukewarm water that you don't need in mid-summer if it makes the whole
installation a lot more expensive and prone to failure.

A rough rule of thumb is that summer DHW is less than 10% maybe as low
as 5% of peak winter space heating requirements. We are just too far
north for solar power to be sensible without market distorting FITs.

I calculated that my annual DHW costs are about £100 quid. My annual
heating costs are now getting on for £2000 of which about £1200 is
between November and March. Plus a couple of hundred for wood.

I have never bothered to compute the exact hot water cost in detail but
in the coldest part of the winter we burn ~100L/week and in the summer
months on hot water only it is down to 100L over 4 months. The
difference in burn rate from winter to summer is about 6L/wk DHW vs
100L/wk for space heating. Actually now distorted by the wood burning
stove and 2T of wood during the coldest months.

The complexity of the plumbing (and distance from hot water tank to
where the solar panel would have to be) has so far put me off doing
anything for solar DHW. I have a feeling that the old oil boiler would
rust up if it was not fired up periodically during the summer. The CH
pump certainly does its best to seize up after every summer...

That's on a fully insulated house run as cold as I dare.

Likewise. Except that parts of our house are very thick solid stone
walls and not amenable to cavity wall insulation for obvious reasons.

--
Regards,
Martin Brown

On May 25, 6:42*am, harry wrote:
On May 24, 10:00*pm, "www.GymRatZ.co.uk"









wrote:
On 24/05/2012 21:39, Rod Speed wrote:

And if you want something that really heats the water
properly to high temps, its better to have two separate
systems, one for the electricity and one for the water.

Thanks for input Rod
It all revolves around a proposed extension which will (if given the
go-ahead) give us a 15m long x 2.5m pitched roof with SW elevation.

Given that our house is heated just fine for both UFH and Rad. zones
with max. flow rate of 55 degrees C and we're sort sort of down south
(Bristol latitude) if I could get 55 degrees from such a system for 4
hours of the day in deep winter it _might_ prove to be of significant
benefit by offsetting boiler run/start time into the evening.

Perhaps a summer/winter diverter that could (pre)heat DHW in summer and
CH in winter...

Just foundhttp://www.newformenergy.com/
and bounced them a few questions.

All depends on planning app. at the moment though... (and of course
price of such a hybrid solution)
8¬|

Cheers - Pete
--http://www.GymRatZ.co.uk-Fitness+Gym Equipment.

Such a device is pointless. *You don't need any house heating when the
sun is shining. Heat collected in Winter is minimal in the UK climate.
Spend your money on insulation.
Rod is from Oz ergo most of the stuff he rambles on about is
irrelevant here in the UK.http://www.flickr.com/photos/ara-chl...7627608971673/

Whose house is that? It must be like living in a tomb.

"www.GymRatZ.co.uk" wrote
harry wrote

Such a device is pointless. You don't need any house heating when the
sun is shining. Heat collected in Winter is minimal in the UK climate.

But if the cooling of the PV increases their output and can provide a
20+ (?) degree temperature rise to pre-heat mains cold water before it
goes through the combi. that could in it's self could make quite a
reduction
on gas consumption during summer months for DHW would it not?

Yes, but I doubt you'd actually get a significant cooling of the PV array.

So you might well be better off with a dedicated solar hot water system
instead, particularly as hybrid systems are significantly more expensive
than a simple PV array from china and a dedicated solar hot water system.

(throwing ideas in the air for discussion and dissection)

Just don't stand underneath them. Can end up with tears before bed time.

wrote:
On May 25, 6:42 am, harry wrote:
On May 24, 10:00 pm, "www.GymRatZ.co.uk"









wrote:
On 24/05/2012 21:39, Rod Speed wrote:
And if you want something that really heats the water
properly to high temps, its better to have two separate
systems, one for the electricity and one for the water.
Thanks for input Rod
It all revolves around a proposed extension which will (if given the
go-ahead) give us a 15m long x 2.5m pitched roof with SW elevation.
Given that our house is heated just fine for both UFH and Rad. zones
with max. flow rate of 55 degrees C and we're sort sort of down south
(Bristol latitude) if I could get 55 degrees from such a system for 4
hours of the day in deep winter it _might_ prove to be of significant
benefit by offsetting boiler run/start time into the evening.
Perhaps a summer/winter diverter that could (pre)heat DHW in summer and
CH in winter...
Just foundhttp://www.newformenergy.com/
and bounced them a few questions.
All depends on planning app. at the moment though... (and of course
price of such a hybrid solution)
8¬|
Cheers - Pete
--http://www.GymRatZ.co.uk-Fitness+Gym Equipment.
Such a device is pointless. You don't need any house heating when the
sun is shining. Heat collected in Winter is minimal in the UK climate.
Spend your money on insulation.
Rod is from Oz ergo most of the stuff he rambles on about is
irrelevant here in the UK.http://www.flickr.com/photos/ara-chl...7627608971673/

Whose house is that? It must be like living in a tomb.

Its harries passive haus.

Costs a bomb to build and to misquote Vivian stanshall 'when harry broke
a fast, you cursed double glazing'


--
To people who know nothing, anything is possible.
To people who know too much, it is a sad fact
that they know how little is really possible -
and how hard it is to achieve it.

wrote in message
...
On May 25, 6:42 am, harry wrote:
On May 24, 10:00 pm, "www.GymRatZ.co.uk"









wrote:
On 24/05/2012 21:39, Rod Speed wrote:

And if you want something that really heats the water
properly to high temps, its better to have two separate
systems, one for the electricity and one for the water.

Thanks for input Rod
It all revolves around a proposed extension which will (if given the
go-ahead) give us a 15m long x 2.5m pitched roof with SW elevation.

Given that our house is heated just fine for both UFH and Rad. zones
with max. flow rate of 55 degrees C and we're sort sort of down south
(Bristol latitude) if I could get 55 degrees from such a system for 4
hours of the day in deep winter it _might_ prove to be of significant
benefit by offsetting boiler run/start time into the evening.

Perhaps a summer/winter diverter that could (pre)heat DHW in summer and
CH in winter...

Just foundhttp://www.newformenergy.com/
and bounced them a few questions.

All depends on planning app. at the moment though... (and of course
price of such a hybrid solution)
8¬|

Cheers - Pete
--http://www.GymRatZ.co.uk-Fitness+Gym Equipment.

Such a device is pointless. You don't need any house heating when the
sun is shining. Heat collected in Winter is minimal in the UK climate.
Spend your money on insulation.
Rod is from Oz ergo most of the stuff he rambles on about is
irrelevant here in the UK.
http://www.flickr.com/photos/ara-chl...7627608971673/

Whose house is that?

His.

It must be like living in a tomb.

Entirely appropriate given that he has one foot in the grave.

And it's a ****ed passive solar system. The windows are MUCH too
short vertically and there is no eave to stop solar input in summer either.

On May 25, 7:17*am, "Rod Speed" wrote:
"harry" wrote in message

...





On May 24, 10:00 pm, "www.GymRatZ.co.uk"
wrote:
On 24/05/2012 21:39, Rod Speed wrote:

And if you want something that really heats the water
properly to high temps, its better to have two separate
systems, one for the electricity and one for the water.

Thanks for input Rod
It all revolves around a proposed extension which will (if given the
go-ahead) give us a 15m long x 2.5m pitched roof with SW elevation.

Given that our house is heated just fine for both UFH and Rad. zones
with max. flow rate of 55 degrees C and we're sort sort of down south
(Bristol latitude) if I could get 55 degrees from such a system for 4
hours of the day in deep winter it _might_ prove to be of significant
benefit by offsetting boiler run/start time into the evening.

Perhaps a summer/winter diverter that could (pre)heat DHW in summer and
CH in winter...

Just foundhttp://www.newformenergy.com/
and bounced them a few questions.

All depends on planning app. at the moment though... (and of course
price of such a hybrid solution)
8¬|

Cheers - Pete
--http://www.GymRatZ.co.uk-Fitness+Gym Equipment.
Such a device is pointless. *You don't need
any house heating when the sun is shining.

More mindless drivel, most obviously with existing
houses that arent practical to redo as passive solar etc.

Heat collected in Winter is minimal in the UK climate.

Wrong, as always. Passive solar works fine there, fool.- Hide quoted text -

- Show quoted text -

I have a passive house. I know what works and what doesn't.

On May 25, 8:53*am, "Dave Liquorice"
wrote:
On Fri, 25 May 2012 01:22:37 +0100,www.GymRatZ.co.ukwrote:
There is no reason why one couldn't install a larger collector but
what do you do with all that heat in the summer when you have no
space heating requiremen?

Ah well I was also thinking about that one earlier...
The front garden/drive etc could be used as an Interseasonal Thermal
Store.

Do the maths. To store a useful amount of heat you will need a big
store and lots of insulation. When planning the system here I did
half look at how big a store would need to be to supply a days heat.
I think it came out at about 1500l of water at 90C. So to store just
a months worth of heat it's getting a bit big...

I know of a system with ground source heat pump and solar thermal. If
the solar thermal gets the store to it's maximum safe temperature it
dumps the any excess heat into the ground but having thought about it
that is just a heat sink the heat won't stay there 'till the winter
to be pumped back out.

--
Cheers
Dave.

Exactly so. A passive house need only get 5% of it's energy from non
solar sources. So that much expense for active heating makes no sense
at all.

Another point is that the heat has leaked away by the time you need
it.

On May 25, 9:36*am, "www.GymRatZ.co.uk"
wrote:
On 25/05/2012 08:53, Dave Liquorice wrote:

I know of a system with ground source heat pump and solar thermal. If
the solar thermal gets the store to it's maximum safe temperature it
dumps the any excess heat into the ground but having thought about it
that is just a heat sink the heat won't stay there 'till the winter
to be pumped back out.

I read on t'internet that heat moves very slowly through the ground.
I think it was in the region of 1 metre / month.

So theoretically.... 30M bore holes would swallow up (and retain) a hell
of a lot of dumped solar thermal, might take several summers to reach
max. "working" temp though.

However.... if the heat has to be extracted back via GSHP the finances
of such a project render it completely pointless.

;¬)

--http://www.GymRatZ.co.uk- Fitness+Gym Equipment.

The rate heat moves through anything is driven by conductivity but
also by temperature difference.
A very major factor is if or not there is ground water. Ground water
is often not stationary but moves through the ground and takes any
stored heat with it.

On May 25, 9:45*am, "www.GymRatZ.co.uk"
wrote:
On 25/05/2012 06:42, harry wrote:

Such a device is pointless. *You don't need any house heating when the
sun is shining. Heat collected in Winter is minimal in the UK climate.

But if the cooling of the PV increases their output and can provide a
20+ (?) degree temperature rise to pre-heat mains cold water before it
goes through the combi. that could in it's self could make quite a
reduction on gas consumption during summer months for DHW would it not?

(throwing ideas in the air for discussion and dissection)

--http://www.GymRatZ.co.uk- Fitness+Gym Equipment.

The final solution is massive insulation, large south windows and
small north windows, all with insulated shutters.
KISS.
Keep It Stupid Simple
Apart from the PV array, you need no high tech crap.
I have no gas, oil or electric heating.
I have thermal mass.

It works. I have such a house which was converted from an ordinary
house.
I am writing a book.

On May 25, 9:56*am, Martin Brown
wrote:
On 25/05/2012 09:45,www.GymRatZ.co.ukwrote:

On 25/05/2012 06:42, harry wrote:

Such a device is pointless. *You don't need any house heating when the
sun is shining. Heat collected in Winter is minimal in the UK climate.

But if the cooling of the PV increases their output and can provide a
20+ (?) degree temperature rise to pre-heat mains cold water before it
goes through the combi. that could in it's self could make quite a
reduction on gas consumption during summer months for DHW would it not?

(throwing ideas in the air for discussion and dissection)

The problem is one of cost effectiveness and complexity.

There is no point in saving power usage to create vast quantities of
lukewarm water that you don't need in mid-summer if it makes the whole
installation a lot more expensive and prone to failure.

A rough rule of thumb is that summer DHW is less than 10% maybe as low
as 5% of peak winter space heating requirements. We are just too far
north for solar power to be sensible without market distorting FITs.

--
Regards,
Martin Brown

Quite right. But that depends on the price of fossil fuel and PV
panels.
Nuclear power is subsidised too.
If I want free hot water, I can turn the immersion heater on when the
sun is shining (PVpower). if I am feelng public spirited, I turn on my
solar thermal array.

On May 25, 10:02*am, The Natural Philosopher
wrote:
Martin Brown wrote:
On 25/05/2012 09:45,www.GymRatZ.co.ukwrote:
On 25/05/2012 06:42, harry wrote:

Such a device is pointless. *You don't need any house heating when the
sun is shining. Heat collected in Winter is minimal in the UK climate..

But if the cooling of the PV increases their output and can provide a
20+ (?) degree temperature rise to pre-heat mains cold water before it
goes through the combi. that could in it's self could make quite a
reduction on gas consumption during summer months for DHW would it not?

(throwing ideas in the air for discussion and dissection)

The problem is one of cost effectiveness and complexity.

There is no point in saving power usage to create vast quantities of
lukewarm water that you don't need in mid-summer if it makes the whole
installation a lot more expensive and prone to failure.

A rough rule of thumb is that summer DHW is less than 10% maybe as low
as 5% of peak winter space heating requirements. We are just too far
north for solar power to be sensible without market distorting FITs.

I calculated that my annual DHW costs are about £100 quid. My annual
heating costs are now getting on for £2000 of which about £1200 is
between November and March. Plus a couple of hundred for wood.

That's on a fully insulated house run as cold as I dare.

--
To people who know nothing, anything is possible.
To people who know too much, it is a sad fact
that they know how little is really possible -
and how hard it is to achieve it.- Hide quoted text -

- Show quoted text -

My PV array is worth £2200/year to me taking into account tax.
I have no heating bill & my electric bill is around £400.
Not very smart are you?

On May 25, 10:34*am, " wrote:
On May 25, 6:42*am, harry wrote:





On May 24, 10:00*pm, "www.GymRatZ.co.uk"

wrote:
On 24/05/2012 21:39, Rod Speed wrote:

And if you want something that really heats the water
properly to high temps, its better to have two separate
systems, one for the electricity and one for the water.

Thanks for input Rod
It all revolves around a proposed extension which will (if given the
go-ahead) give us a 15m long x 2.5m pitched roof with SW elevation.

Given that our house is heated just fine for both UFH and Rad. zones
with max. flow rate of 55 degrees C and we're sort sort of down south
(Bristol latitude) if I could get 55 degrees from such a system for 4
hours of the day in deep winter it _might_ prove to be of significant
benefit by offsetting boiler run/start time into the evening.

Perhaps a summer/winter diverter that could (pre)heat DHW in summer and
CH in winter...

Just foundhttp://www.newformenergy.com/
and bounced them a few questions.

All depends on planning app. at the moment though... (and of course
price of such a hybrid solution)
8¬|

Cheers - Pete
--http://www.GymRatZ.co.uk-Fitness+GymEquipment.

Such a device is pointless. *You don't need any house heating when the
sun is shining. Heat collected in Winter is minimal in the UK climate.
Spend your money on insulation.
Rod is from Oz ergo most of the stuff he rambles on about is
irrelevant here in the UK.http://www.flickr.com/photos/ara-chl...7627608971673/

Whose house is that? It must be like living in a tomb.- Hide quoted text -

- Show quoted text -

It's mine. Why a tomb? All the rooms are better lit than most
houses. Half of the walls is glass.