Siting of panels for solar water heating

Joe Fischer wrote:

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.

The US govt does control policy/law though.

But both the coal industry and the power plants have been spending fortunes cleaning up coal to reduce pollution.

Less toxins is nice, but wont have any effect on CO2 output tho.

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.

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.

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.
1 National new build energy policies can switch from gas and coal to nuke and wind. 2 New build houses can be required to have 6" insulation instead of 2". Saves people money 3 New CH systems can be required to have a programmer for each room, so time and temp can be set for each. Saves people money 4 A quality BS can be set up for cfls so the decent ones are recognised by buyers, and marked properly instead of the nonsense equivalence claims now common. People knowing they can buy quality cfls would mean many more sales. Saves people money 5 filament bulbs can be taxed to prod people to move to cfl - the amount of tax would be low enough not to have much real effect on anyone's purse, and there is little need to buy filament bulbs anyway. Moving to cfl saves money. 6 Legalise car engine conversion for greater mpg. The simplest way to do this is to close off one or more cylinders by removing rocker arms. Saves people money 7 Heavily tax hungry cars at point of sale. Moving people to leaner vehicles reduces costs. Saves people money 8 Increase VED for low mpg cars (annual tax disc), while at the same time offering a free VED bracket for the 5% highest mpg vehicles (this would be a moving target, moved annually to keep it to the top 5%). This could together not change total revenue, though we all know how it'll go in practice. Saves people money by reducing total fuel consumption. 10 Govt to offer a nice fat prize to the person who can design the best of various categories of energy reduction equipment. Eg: - solar space heating - solar dhw - any other enrgy saving tech and so on. The requirements would include good ROI, little or minimal maintnance, and practical diy fitting.
Theres plenty more. The main barriers are lack of genuine belief in the need for it and general ignorance regarding energy saving options, solar design and so on.

There are ways to reduce energy use, like having people move close to where they work, but there isn't a power that can accomplish that.

Fuel taxation would, but I'm not sure this would be productive anyway. More tax incentives for home workers, making up for it with tax on non-homers would also skew the picture and reduce energy use.

Solar energy is primarily a sub-tropic region energy source, and is not being guided in the right direction. Solar panels on the roof, especially retrofitted, is not a good idea, on walls facing the equator is a much better idea. Just one leak caused by installing panels on the roof, and all the savings for 10 years is lost,

Kit mounted atop single storey flat roofs has significant advantages.
FWIW its quite possible to use a controller that detects leaks and shuts off one section of a parallelled system. This would improve reliability, reduce ongoing costs, and extend system lifetimes. But this is only going to be cost effective when the equipment reaches mass production.

roofs don't usually last more than 15 or 20 years, so installing panels on a 10 year old roof is not a good idea.

In Britain average roof lifetime is mesured in centuries.

Bee-hive apartments may be energy efficient with less outside walls, but not everybody is willing to live in an apartment.

Many are though. New build programs could become more apartment block oriented. The British planning system makes extending existing buildings difficult to impossible, and this could also be improved. Larger buildings house more people more energy efficiently.

Really old buildings may be the most difficult to heat, and the trend in the US is larger homes, so nothing is moving in the right direction to save energy.

Its not too hard to retroinsulate old houses.

It seems evident that for solar energy to be affordable by the masses, there has to be a large Do-it-Yourself effort, with the right ideas, and a modular approach that can be done a little at a time is better both for time, and the up front cost.
Joe Fischer

Yes, and its doable. As the real cost of energy increases, and knowledge spreads, courtesy of the www, we see more of it being done.
NT

In article , "Mary Fisher" writes:

"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.

He's posting from the US. In the UK, roof life between significant maintenance events has normally been around 70 years (so you've got 1 year to go Mary;-).
It is likely that with better materials used in recent years, roofs which are less than 70 years old will extend this period, but we don't have figures for them yet, obviously.
-- Andrew Gabriel

Joe Fischer wrote:

On 17 Nov 2006 meow2222@care2.com wrote:
A typical brick or block house should be big enough, assuming its decently insulated. Mine doesnt lose a whole lot of temp overnight. One simply sets the solar heating stat to above the temp of the gas CH, make use of that comfort zone. NT
A house built for solar heat, or any type of efficient heating, should have a triple wall construction, in contrast to present common designs, a well insulated outer wall, a thick masonry wall (concrete block), and either face brick on the inside, or furring strips and plaster (drywall). There are many concrete block houses, but almost all have the block on the outside.
This is as bad as all the industrial buildings having north facing windows.
Joe Fischer

It would be a lot more material efficient to have 2 wall leafs than 3, with the inner being thicker than the outer, eg 2.5" outer leaf, 1" uninsulated cavity, 6" insulated cavity then 6" inner leaf. SS wall ties would give the 2.5" leaf good stability.
Triplewall construction only gives a 2nd cavity, and this can be achieved at far lower cost in other ways.
NT

"Andrew Gabriel" wrote in message

In article , "Mary Fisher" writes:
"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.
He's posting from the US.

And it's different there?

In the UK, roof life between significant maintenance events has normally been around 70 years (so you've got 1 year to go Mary;-).

Ours hasn't needed any maintenence and my father back-pointed the (rosemary) tiles when the house was new. Nothing has shifted - we keep an eye on it but apart from a bit of flaunching round the chimney (not really the roof) nothing needs doing.
If only the rest of the house were as good :-)

Mary

On Sat, 18 Nov 2006 08:15:43 +0000 someone who may be Andy Hall wrote this:-

I wonder how much the sales people focus on any of the others than the possibility that the customer might save money. Maybe.

Are you expecting those of us in favour of such things to apologise for the way some salespeople try and sell them?

In terms of worthiness, I suppose it depends on what one means by worthiness. Incrementalism is a poor argument at the best of times and one might have hoped that people would be smart enough to realise that they won't save the world through installing a solar panel.

People said much the same sort of thing to a very great man when he took on the largest empire in the world over the salt tax. As events proved they were wrong and the largest empire the world has ever seen was humbled.

-- David Hansen, Edinburgh I will *always* explain revoked encryption keys, unless RIP prevents me http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

wrote:

Ian Stirling wrote:
... 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.
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. 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.

Watching you wave your hands about solar heating is like watching a 2-year-old draw a 300' tree with a 1" diameter trunk or hearing an earthy-crunchy person say he can heat his house by running rainwater from his roof through his microhydro plant :-)
Numbers give a sense of perspective in this energy newsgroup.
Nick

On 2006-11-18 11:20:51 +0000, David Hansen said:

On Sat, 18 Nov 2006 08:15:43 +0000 someone who may be Andy Hall andyh@hall.nospam> wrote this:-
I wonder how much the sales people focus on any of the others than the possibility that the customer might save money. Maybe.
Are you expecting those of us in favour of such things to apologise for the way some salespeople try and sell them?

Not at all. It just further demonstrates how thin the tangible arguments actually are.
If people want to spend their money on fashion, positioning, looking good, toys, whatever, that's perfectly fine and it's also perfectly fine for sales people to sell to them on that basis.
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.

In terms of worthiness, I suppose it depends on what one means by worthiness. Incrementalism is a poor argument at the best of times and one might have hoped that people would be smart enough to realise that they won't save the world through installing a solar panel.
People said much the same sort of thing to a very great man when he took on the largest empire in the world over the salt tax. As events proved they were wrong and the largest empire the world has ever seen was humbled.

Quite. However, the two scenarios are not at all comparable. That is a very weak argument. David and Goliath would have been a better one than Gandhi. Besides, government policy hasn't changed. They are still trying to discourage people from consuming too much salt.

On Sat, 18 Nov 2006 12:15:45 +0000 someone who may be Andy Hall wrote this:-

However, when taken to the realities of
- Does it save money with all factors taken into account?

Part of the answer is that it depends on the wind resources available at the particular site. Another part of the answer is that it is usually better (in financial as well as environmental terms) to save energy than generate it. Both these are things groups like Friends of the Earth have said for a long time.

- Does it save the planet with all factors taken into account?

The question is does it reduce greenhouse gas emissions? The answer to this question is yes, in nearly all cases. However, there may well be other ways to reduce carbon dioxide emissions more, which is why Friends of the Earth Scotland say, "Done what you can to make your home more energy efficient? Made the switch to a green energy supplier? Want to do more to support green energy? If you own your own home then you may be in a position to generate your own energy. In some cases you could even get paid for the energy you produce." http://www.foe-scotland.org.uk/nation/microrenewables.html
Will one wind turbine "save the planet" is a question the antis like to ask, presumably because they think it is a killer question. However, the answer to this question is the same as it is on many other things, a lot of little things add up to a lot.

-- David Hansen, Edinburgh I will *always* explain revoked encryption keys, unless RIP prevents me http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

On 2006-11-18 12:52:22 +0000, David Hansen said:

On Sat, 18 Nov 2006 12:15:45 +0000 someone who may be Andy Hall andyh@hall.nospam> wrote this:-
However, when taken to the realities of
- Does it save money with all factors taken into account?
Part of the answer is that it depends on the wind resources available at the particular site. Another part of the answer is that it is usually better (in financial as well as environmental terms) to save energy than generate it. Both these are things groups like Friends of the Earth have said for a long time.

A bit woolly....

- Does it save the planet with all factors taken into account?
The question is does it reduce greenhouse gas emissions? The answer to this question is yes, in nearly all cases. However, there may well be other ways to reduce carbon dioxide emissions more, which is why Friends of the Earth Scotland say, "Done what you can to make your home more energy efficient? Made the switch to a green energy supplier? Want to do more to support green energy? If you own your own home then you may be in a position to generate your own energy. In some cases you could even get paid for the energy you produce." http://www.foe-scotland.org.uk/nation/microrenewables.html
Will one wind turbine "save the planet" is a question the antis like to ask, presumably because they think it is a killer question. However, the answer to this question is the same as it is on many other things, a lot of little things add up to a lot.

OK. Let's say (to pick a number) that 20% of UK households installed solar panels and or personal windmills.
What would be the estimates for energy saved and reduction in CO2 emission, assuming that the energy replacement was of the highest CO2 emitting means of power generation?
I am thinking of these as a realistic maximum of households (make it some other percentage if you like) and that it would be addressing the most affecting energy sources. In reality, the existing power generators would take the most expensive production out of service first rather than the dirtiest, but let's be generous and leave that aside as well.
Then extrapolate the figures for a) Western Europe and b) Kyoto participants.

On Sat, 18 Nov 2006 13:13:43 +0000 someone who may be Andy Hall wrote this:-

Part of the answer is that it depends on the wind resources available at the particular site. Another part of the answer is that it is usually better (in financial as well as environmental terms) to save energy than generate it. Both these are things groups like Friends of the Earth have said for a long time.
A bit woolly....

Simplistic answers, particularly in marketing leaflets, are something you criticised in other posts. Non-simplistic answers can be called woolly, but most interesting questions cannot be answered with sound bites.
On your other question, I'm not jumping to requests for ever more detailed figures. Information has been produced by others should people wish to follow it up, though there is still much work to do on the subject.
People could also wait for the evidence given to the "enquiry" on the subject by the DTI. At the moment they are calling for evidence. I see that OFGEM are doing something similar.


-- David Hansen, Edinburgh I will *always* explain revoked encryption keys, unless RIP prevents me http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

nicksanspam@ece.villanova.edu wrote:

meow2222@care2.com> wrote: Ian Stirling wrote:
... 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.
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. 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.
Watching you wave your hands about solar heating is like watching a 2-year-old draw a 300' tree with a 1" diameter trunk or hearing an earthy-crunchy person say he can heat his house by running rainwater from his roof through his microhydro plant :-)
Numbers give a sense of perspective in this energy newsgroup.
Nick

This house stays within comfort zone temp swing overnight. If you wish to add some figures to this, take things forward another informational step, great.
NT

On 2006-11-18 14:18:39 +0000, David Hansen said:

On Sat, 18 Nov 2006 13:13:43 +0000 someone who may be Andy Hall andyh@hall.nospam> wrote this:-
Part of the answer is that it depends on the wind resources available at the particular site. Another part of the answer is that it is usually better (in financial as well as environmental terms) to save energy than generate it. Both these are things groups like Friends of the Earth have said for a long time.
A bit woolly....
Simplistic answers, particularly in marketing leaflets, are something you criticised in other posts.

Correct.

Non-simplistic answers can be called woolly, but most interesting questions cannot be answered with sound bites.

Also correct. Verifiable figures produced by a disinterested party would serve very well.

On your other question, I'm not jumping to requests for ever more detailed figures. Information has been produced by others should people wish to follow it up, though there is still much work to do on the subject.

Mmmm.....

People could also wait for the evidence given to the "enquiry" on the subject by the DTI. At the moment they are calling for evidence. I see that OFGEM are doing something similar.

Even more mmmmm......

"David Hansen" wrote in message

On Sat, 18 Nov 2006 12:15:45 +0000 someone who may be Andy Hall andyh@hall.nospam> wrote this:-
However, when taken to the realities of
- Does it save money with all factors taken into account?
Part of the answer is that it depends on the wind resources available at the particular site. Another part of the answer is that it is usually better (in financial as well as environmental terms) to save energy than generate it. Both these are things groups like Friends of the Earth have said for a long time.
- Does it save the planet with all factors taken into account?
The question is does it reduce greenhouse gas emissions? The answer to this question is yes, in nearly all cases. However, there may well be other ways to reduce carbon dioxide emissions more, which is why Friends of the Earth Scotland say, "Done what you can to make your home more energy efficient? Made the switch to a green energy supplier? Want to do more to support green energy? If you own your own home then you may be in a position to generate your own energy. In some cases you could even get paid for the energy you produce." http://www.foe-scotland.org.uk/nation/microrenewables.html
Will one wind turbine "save the planet" is a question the antis like to ask, presumably because they think it is a killer question. However, the answer to this question is the same as it is on many other things, a lot of little things add up to a lot.

-- David Hansen, Edinburgh I will *always* explain revoked encryption keys, unless RIP prevents me http://www.opsi.gov.uk/acts/acts2000/00023--e.htm#54

well the best way in regard to my point of view would to use effeicently designed wrought iron structure in the top of the roof its lets u to make the panels face where ever u like. and the expert in your area would definetely know what is the angle the panel should be put for getting maximum energy out of it. hope this works! Will wrote:

We moved into our two storey, reconstituted stone-built, pitched-roof house in April.
We decided early on to get as much of our energy as possible from renewables.
A couple of weeks ago we signed up for a solar heating system. I've looked at a few and this seems like a very good system.
The marketing wonk who visited us (who had obviously been in the pub first) declared that our directly west-facing roof would be perfectly adequate to site the panels. It is a very clear prospect as it faces a flat field, and there are no trees in the line of sight.
However, when their surveyor came to measure up he said that the west-facing roof was inadequate and the panels would have to be sited on the gable-end wall (facing south).
I can't see how this would be an improvement. Even though the panels would be angled away from the wall (mimicing the roof's pitch) they would certainly be obscured by the angle of the roof for at least part of the morning and part of the evening.
Am I wrong? The alternative, according to the surveyor, would be double the number of panels with half on the east pitch and the other on the west.
Many thanks
Will.

In message , OldNick writes

On Sat, 18 Nov 2006 08:09:03 +0800, OldNick <nsremovable@iinet.net.au wrote:
Actually I am not sure I _do_ agree. Still interested in your basis.

Nick - the fact that you live upside down doesn't mean that you have to top post
it's just a sign of being mentally retarded - err .. like a septic

On Fri, 17 Nov 2006 22:12:22 GMT, raden wrote:
Well, having done a few quick calcs, I tend to agree, unless you had a HUGE heating panel to get it active the next morning.
However, I would be interested in your calcs and figures, as you seem to feel strongly about this <G
Like ...
what time the sun rises in winter, how big a thermal store you would need to store sufficient heat overnight
it's just not very realistic for heating

-- geoff