Siting of panels for solar water heating

In message , meow2222@care2.com writes

John Beardmore wrote: In message , SJC writes
Solar thermal panels for space heating is one of the ways we can save lots of fossil fuels in the future.
I really doubt it !
Cheers, J/.
Whys that?

Because I strongly suspect that there will be cheaper ways to achieve the same thing, because the UK doesn't have that many cold but bright days, because the sun doesn't shine when we need space heating, because passive solar design is more cost effective.

http://www.builditsolar.com/ & http://www.builditsolar.com/Projects/SpaceHeating/Space_Heating.htm

Yes - and there has been some good work done at one of the Glasgow universities, and there is a Nu Aire system on sale in the UK that we have looked at installing for somebody, and the Carbon Trust have waxed a bit lyrical in some of their training about merging all sorts of streams of low grade heat to heat space, but all of these things seem to require a lot of capital cost and super insulated buildings to be viable, and they also require buildings to use, in some cases, whole walls as solar collectors which again rather begs the question, would passive solar be cheaper ? It also raises planning issues, which knowing the UK, may take decades to resolve.
Cheers, J/. -- John Beardmore

In message , Joe Fischer writes

On Sat, 18 Nov 2006 raden wrote:
In message x Joe Fischer joe@westpointracing.com> writes On Sat, Andy Hall wrote: All of this is focus in completely the wrong area. All the time that the U.S. continues not to make much of a federal effort in terms of emissions control
The federal government doesn't own many fossil fuel power plants. But both the coal industry and the power plants have been spending fortunes cleaning up coal to reduce pollution.
Reducing demand might help too
That's why we buy everything from China and Asia now, so we don't use so much energy in factories. :-)

Aha problem shifting
these Ameristanis think of everything

and China is opening a new coal fired power station weekly, all of this other stuff makes so little difference that it is a waste of time on environmental grounds.
There is a lot of USA bashing, but other than the French nuclear industry, I see very little about what other countries are doing to reduce CO2 emissions.
Mainly because the USA is by far he most energy hungry country
And the biggest energy producing country.

Yeah ... the idea is to sort of reduce energy

But if the A-380 is ever used by airlines, fuel use all over the world will go up.

Errrrrr ...
compared to Septics who fly like we take the bus ?

I would suggest that efforts are turned towards dealing with the major issues, and that does not include getting GW Bush to sign up for silly politicised nonsense like Kyoto, but for serious efforts for change.
Actually, the only really viable change can only come from alcohol production from bio sources, there can be some CO2 sequestration but not on the scale that would be needed to make a difference.
Even if the case for CO2 induced global warming could be demonstrated clearly and proven beyond doubt, there is nothing much that can be done without people freezing
How did mankind survive 200 years ago ?
Depends on where, eskimos wore skins, and ate lots of blubber for energy. Rural Eastern Europe lived in shacks with dirt floors, and on real cold nights invited the cattle and pigs in, and cuddled with them. I guess maybe in the UK, coal was being burned for heat.

Well, when I was a kid, there was no central heating (or air con), yes, a couple of coal / wood fires in the house
Strangely I'm still here to tell the tale

or giving up income.
Well that's the rub - when you're living beyond your (ecological) means, you have to cut back
Unless Saudia Arabia keeps selling oil.

?

The same as is happening to North Sea cod - over-fishing means that we're reaching the tipping point from which it seems unlikely that the stocks will recover. Factory farming will be useful in the future, but there's a chasm between then and now
I don't think the energy crisis is exactly analogous to over fishing, but I like the idea of fish farms.

Not exactly, but in some ways, a good parallel (of course, you can eat fish when you set fire to them)

In 1958 I experimented with raising guppies in salt water until they were adults, they were sterile in ocean water, bur when slowly accustomed back to fresh water, they were extremely healthy and prolific. If the number of young I got from 15 pairs were to be extrapolated over 10 years, there would be enough to feed the world.
similarly with energy consumption
I am all for planting every square acre in sugar cane, potatoes, beets, water melon, and everything that can be used to make ethanol. But that may not work in every country.
... which needs a cunning plan, not people turning off their TVs and disconnecting phone power supplies
There is time, at least in the US, but I see Europe in a critical situation, with an urgent need to do something to assure that people don't freeze.
Even if there is a crisis, action will be fast, and a solution will be worked out

No, there will be an eleventh hour panic whuich will be too late

(unless you are talking about sea level rise, which is going to happen anyway). My problems are just keeping warm in 2 rooms and bath (the rest of the house is not heated), and trying to keep from being bored.
Which is where I'm going to have to sign off and go for my solution

upstairs awaits
-- geoff

In message , Ian Stirling writes

In uk.d-i-y John Beardmore wrote: In message , Ian Stirling writes In uk.d-i-y raden wrote: In message , Eric Sears phoneme@025379386.for.email.address> writes
I think the usual assumption is that the building will have significant thermal mass internally, in the form of an insulated concrete slab, or something.
:)
That's not a standard feature of the solar water heating systems we install. You are getting into the realm of the Hockerton Housing Project design strategy here, but this has been criticised because of the environmental impact if making the concrete. Ultra low thermal capacity buildings also have something to commend them as long as they can dump heat when required.
I'm not convinced it has no place - you would admittedly need a very large additional thermal mass - a ton or two of water probably, to keep the heating on overnight, with a 10-20C drop.
This is not of itself very expensive, though the places it can be easily installed are of course going to be very limited.

Yes - Our architect dissuaded me from putting a few cube under the extension of our house.
Cheers, J/. -- John Beardmore

In message , meow2222@care2.com writes

Ian Stirling wrote: In uk.d-i-y John Beardmore wrote: In message , Ian Stirling writes
A decently designed solar space heating system would not be using water in the first place. Picking hydronic for space heating is pretty much a design death blow.
Secondly, an entirely different method would be used to maintain temp after dark.

I suspect the notion was that the water would be a heat store.

There is a comfort zone, not just one fixed temp at which people are cosy. Heat to as high in that zone as solar power provides, and you have n hours after sundown of sufficient warmth. N depends on design details.

If you go down the high thermal capacity route.
Cheers, J/. -- John Beardmore

On 2006-11-19 14:05:05 +0000, "Dave Liquorice" said:

On Sun, 19 Nov 2006 10:24:50 -0000, Mary Fisher wrote:
We have all of those apart from hurricanes,
We've had the odd one .... and several tail ends.
I guess it depends how you define "hurricane". Is it the simple Beaufort Scale sustained winds of over 72mph (*not* gusts) at a given place or a real hurricane or typhoon, driven by warm Sea Surface Temperatures. 26C is about the lowest SST required for huricanes to maintain themselves having formed over warmer water. The waters around the UK are pushed to get above 15C. Also bear in mind hurricanes are *HUGE*, thier sheer size never really comes across in the news reports.
If the eye of yer average hurricane passed over Manchester, you would have sustained winds >72mph from the South Lakes to North Birmingham and Tropical Storm force winds (>39mph) from Glasgow to London. The destruction this would bring to the UK would be treemendous. It would make the '87 look like a gentle breeze.

Ah, but if you've ever had the misfortune to watch local TV in the U.S. you would have seen that anything more than the gentlest breeze is a storm and that a tree falling over is major destruction.

On 2006-11-19 13:55:43 +0000, John Beardmore said:

In message , Andy Hall writes
However, when taken to the realities of
- Does it save money with all factors taken into account?
- Does it save the planet with all factors taken into account?
The answers become very thin indeed.
The answers seem to be yes and yes with UK domestic systems typically pulling in 1 to 4 MWh per year depending on panel area and hot water use.
Granted the more prolific users will displace the most CO2 with them.
Cheers, J/.

I did say with *all* factors taken into account.

In message , meow2222@care2.com writes

John Beardmore wrote:
To be honest, while what you say was true 10 years ago, the difference in cost per area is now pretty small, and the prices we quote to end users are much the same per area for FP and ET, because while ET is slightly more expensive, installation is easier and safer in lifting and handling terms, if not actually quicker.
Cheers, J/.
I suppose thats true of professional installs on rooftops, I'm thinking more of diy installs, where the cost for a decent area of tubes is way above that of flat panels,

But that's my whole point. At least in the UK, the prices are now pretty similar.

Flat panels can give much better performance at ground level or on a flat roof, as 1 or 2 reflectors are easily added to give anything from 1-2 suns.

Not sure why the same can't be true of ET systems ?

Equipment on a flat roof ditto, mounting the panel either at an angle from roof to wall or else flat on the wall, reflector below.

I guess the bug bear with that is getting end users to keep the reflectors clean, especially if they are flat.

I guess the ultimate is a 3 zone system, with a drain heat exchanger providing the 1st stage of heat input,

Maybe. My understanding is that the people who have tried these in the UK have not found them cost effective, and I'm not sure what the regulatory position is either.
Guess energy prices may have changed the first of those at least !

flat panels the 2nd (with reflectors for best performance), and vac tubes the last.

Possibly. We've done cylinders / heat stores that go
Oil
Wood
Solar
and have also considered
Oil
Solar
Heat pump

Perhaps one day the equipment will be cheap enough for this to be the done thing.

Or more likely, energy prices will be high enough to justify it.
Cheers, J/. -- John Beardmore

In message , cynic writes

I installed a system a few weeks ago. My vacuum tube array collector is vertical on the gable end. I was faced with a cylinder replacement and decided to go solar rather than stay limited to fossil.

OK. Reflector below ?

The whole batch of kit and pipes came to �1100.

Does that include pump, controller, antifreeze etc ?
What's the collector area ? Who made the panel ?

I was dubious about the effectiveness of having the panel vertical so I have used 4 "L" brackets to mount it to the wall. If I find it lacks performance when the spring comes round I can simply extend the bottom brackets with mild steel bar.

You should certainly be able to boost it some.

with the present dull weather we do notice an elevation of the temperature of the cylinder bottom by about 15 to 20 degree C on many days (the sensor is about 300mm above the base of the cylinder)

Where is that relative to the solar coil ?

It will be interesting to see what happens to our energy bill over the next twelve months. Obviously I would like a decent saving but its an experiment with a potential for economy

Let us know how it goes !
Cheers, J/. -- John Beardmore

In message , Joe Fischer writes

"cynic" wrote:
Vacuum tube arrays could possibly be produced fairly cheap, just as 4 foot fluorescent tubes only cost 99 cents the last time I bought them, but I don't have much hope of seeing them sold to the DIY gang in small quantities at a good price.

It's getting better, mostly thanks to the Chinese !
Cheers, J/. -- John Beardmore

In message , raden writes

In message , John Beardmore wookie@wookie.demon.co.uk> writes
I don't see what my folks signed for as being economically viable
No, but I think our clients divide into at least four categories.
People that want to save the world.
Well, they really aren't going to, are they
They've been taken in by the con

They certainly aren't going to save it single handed, and no doubt they appreciate that, but they'd rather move towards solving the problem, than gratuitously make it worse.

The reality is that the total energy demand of the UK is insignificant when compared to that of the USA and the potential consumption of China, India and other fast developing nations

Well - obviously we should all invest in patio heaters then !

One thing which I have not come across is anyone publishing the manufacturing footprint i.e. energy require and CO2 created in manufacturing the system, keeping the factory open, maintaining reps cars, etc

I've not got an LCA to hand, but my understanding is that they have been done for various renewables and they have been favourable.
I can't speak for other installers, but the ones I know of which are small and local don't use reps, though the national ones that do, presumably do so because it is more efficient financially - I can't say if it's better environmentally.
One development in the UK is state intervention in the market to accredit installers and equipment. Accredited products and installers are listed centrally, so this cuts down on advertising and some other overheads, and facilitates comparisons between installers and products, as well as helping consumers identify who is local to them. Although there are aspects of state intervention that are a pain in the bum such as keeping some capable people out of the market place, for those of us that are accredited, it does make us easy to find and reduce some of our overheads.

People that like interesting toys.
FSVO interesting

?

People that want to set an educational example.
probably
People that want to save money.
Given that the only realistic saving is in hot water (an optimistic 70%), not house heating (when it's REALLY required) or cooking
and seeing the cost of these systems (>�5k) I fail to see how most people would see a payback in less than 10 years

I don't think we've ever charged more than �3,700 for a domestic system, and that was 7.2 sqm of evacuated tubes which is on the large side after all.

All three seem worthy in one respect or another.
Not really

Well - ymmv.

Another category may also creep in.
People that follow fashion.
I remember hearing last week "Solar heating is the double glazing of the 21st century"
... sounds about right to me

Well - in the sense that some installers are trying to sell systems in the 6,000 to 12,000 range I agree, but how many people these days would choose to revert to single glazing, especially given recent fuel price increases ?
Cheers, J/. -- John Beardmore

In message , meow2222@care2.com writes

Joe Fischer wrote: On 18 Nov 2006 meow2222@care2.com wrote: Joe Fischer wrote: On Sat, Andy Hall wrote:
This is because US uses a lot more energy per person than other coutries. Where the european drive is more toward efficient use of more limited resources, the US approach is still generally excess and waste.
Most countries in Europe have no choice,

I'm not quite sure in what sense ?

Even if the case for CO2 induced global warming could be demonstrated clearly and proven beyond doubt, there is nothing much that can be done without people freezing or giving up income.
Oh, there is.
First bear in mind convincing evidence would cause many more people to make greener decisions.
So convince me.
No, you missed what I meant. We dont have anything convincing, if/when we do, people may take more notice.

Seems to me that some people need more convincing than others.
Polar ice melt, measured temperature increase, CO2 emission rates and the properties of CO2 will do for me for now. No doubt our understanding will improve in due course.

For both space heating and gasoline, economics is the determining factor, people are hurting, and have no way to do much. They really can't afford to change cars, they owe on the one they are driving.
what does a rock bottom ac unit cost? How much does it save per year on heating, using it as a winter heat pump? Sure some cant stump up the $200, but also some can. Increasing awareness improves things, even if only some do it.

Think they cost a lot more than that in the UK.

I dont see any reason for anyone to change cars.

But replacing with better ones is good !

roofing __MUST__ be done so that gravity drain without cement or caulking is accomplished, and it is difficult to do that and still put screws through the roof to mount panels.
Oh, we do that without any difficulty. Steelwork is slipped under the slates and secured on the inside.

Even the caulking approach has its place.

But of more significant is new build, where any type of panel can be integrated into the roof, and replace some of the roofing cover material.

Evacuated tubes ??

Chances are the high cost of energy will cause more people to do things than any talk of global warming, rising sea levels, or even shortage scares.
yes... but I dont think they'll rise anything like as much as is hyped.

:) We'll have to see !

It is important to work on these problems without getting too concerned about the pace things are moving, the majority of people simply do not have the money to do much of anything, and if it costs money to save money, they don't have the money unless they are in a position to borrow the money.
Yes, thats a common problem. Reality is there are very cheap ways to do things when needed. At one house I saw cardboard cavities on solid walls, that can be done for peanuts. Borax fire retardant �1, knife �1, wallpaper glue �1.

Yes - but I'm not sure that such insulation will last too long ?

Plastic film secondary glazing is fairly cheap, though reuse of old glass is a much better bet.

But needs some sort of frame making.

Poverty equals lack of time for such extras, but when theres savings to be had, some will do it, once they know it can be done.

Yes, but it still takes some skill and money, and an ability to assess what will work in given circumstances.
Cheers, J/. -- John Beardmore

John Beardmore wrote:

In message <1163835127.443384.291590@j44g2000cwa.googlegroups. com>, Meow2222@care2.com writes
To understand that they'd need to see the connection between supply & fit cost and the energy input in supplying and fitting it. Very briefly, money is a form of measure of energy.
It may be an indicator, but not a very good one !

I wrote about / explained the money -energy connection in detail just recently, so I dont want to again.
NT

Joe Fischer wrote:

On Sat, 18 Nov 2006 10:09:37 -0000, "Mary Fisher" mary.fisher@zetnet.co.uk> wrote: "Joe Fischer" wrote in message snip
roofs don't usually last more than 15 or 20 years,
WHAT?
Our house was built in 1937 and has its original roof (plus solar water heating panel). Most of the others houses on this estate are the same, the few who have newer roofs have replaced them for reasons other than failure. Mary
What kind of roof, slate or terra cotta tile, or metal?
I guess there are places where a kind of concrete tiles are the most used.
Joe Fischer

Metal roofs are generally considered fit only for outbuildings here. I dont agree, but I'm not the majority. The only folk putting metal roofs on houses here are people with ancient buildings that have had them in the past, and where the character is to be preserved. Having lived with a corrugated metal roof I dont see a problem with them, and didnt mind the rain noise, but few agree.
NT

In message , Joe Fischer writes

It is important to work on these problems without getting too concerned about the pace things are moving,

So best not to do much at all then really ?

the majority of people simply do not have the money to do much of anything,

Best not do anything much then.

and if it costs money to save money, they don't have the money unless they are in a position to borrow the money.

So leave it to the masterly inactivity of market forces as usual then !
J/. -- John Beardmore

In message , Joe Fischer writes

On Sun, 19 Nov 2006 raden wrote:
In message x Joe Fischer joe@westpointracing.com> writes And I am not convinced there is a problem,
There we are, that's the problem
Septics who (in the face of overwhelming evidence) aren't convinced there's a problem
I hope there is a problem with your spelling ability.

I hope not - where ?
-- geoff