Siting of panels for solar water heating

In message , Joe Fischer writes

On Sun, 19 Nov 2006 19:42:44 +0000, John Beardmore wookie@wookie.demon.co.uk> wrote:
In message , Joe Fischer joe@westpointracing.com> writes On 19 Nov 2006 01:36:41 -0800, meow2222@care2.com wrote: The solution really needs to focus on renewable energy, and that should help with any global warming problem,
Seems fair.
if there is one.
Seems probable.
I am searching for something to convince me, right now I am looking for __THE__ current global mean temperature.
Easy - stick a thermometer up it's arse

anywhere in Septicstan would prolly do
-- geoff

In message , John Beardmore writes

In the immediate future, global warming is not the scary thing, volcanic activity on the continent of Antarctica should be the most feared thing by property owners in low lying coastal areas.
And second, maybe volcanic activity in Greenland.
Why these areas as opposed to say Yellowstone ?
Yellowstone is something else entirely, 500,000 years vs 30,000 for ice ages.
Yes, but the geologists tell us that the caldera is rising and that an eruption is any time soon. Granted on a 500,000 year cycle, 'a bit late' can be 10,000 years, but to have the ground rise measurably in a human lifetime should be a cause for concern I would have thought ?
Now, if we could just get Gran Canaria to collapse at the same time ...

-- geoff

In message , Peter Parry writes

On Sun, 19 Nov 2006 20:19:27 +0000, John Beardmore wookie@wookie.demon.co.uk> wrote: In message , Peter Parry peter@wpp.ltd.uk> writes
A great pity the accreditation didn't involve actual testing of devices to prove they worked and that their performance was at least close to the sellers invariably vastly overstated claims.
Too bad you don't know what on earth you are talking about then. That's precisely what the accreditation of equipment does cover !!
Neither of the toy windmills have had any performance testing or validation of performance claims whatsoever. Their "accreditation" is a carry over from Clearskies which didn't require any performance testing of windmills whatsoever.

As I said - for wind, I criticised it, it was fairly weak.

That of solar panels is, to put it mildly, rudimentary.

I don't think so. Have you actually seen any test results, or is this just rank speculation on your part ?

What testing do installers get?

Well - proof of experience by case study or mentored installations, inspection of installations while provisionally accredited, random inspection of installations thereafter. There are also codes of practice, insurance requirements etc, which is plenty of bureaucracy to be going on with thanks.

and offered a report about it if anybody is interested,
Yes please.

You have mail, though as I said in it, please do not redistribute without the consent of CREST. (Happy to ask them if you want to use it for anything in particular.)

As far as I recall the Windsave machine quotes a rated power at a given wind speed - and there is nothing wrong that per se,
Depends if it is accurate as their earlier claims, some of which comfortably exceeded the theoretical maximum a perfect turbine could produce.

Well - I've no reason apart from your cynicism to assume that it won't deliver 1kW at 12 m/s.

though a proper power curve would be nice.
Yes it would, I wouldn't hold your breath waiting for it though.

I don't plan to.

The real problem is that the quoted wind speed is 12 m/s, and there is a cube law between wind speed and the energy that can be extracted. This is something the public - and indeed many of the sales people at B&Q level may not appreciate.
I think the senior sales people appreciate it very clearly

Really ? I doubt most of know a cube law from a short plank ?

and produce copy for their juniors appropriately. That's why they are so enthusiastic about using the wildly optimistic NOABL database (when used for urban wind) with no correction for surface roughness.

Just how enthusiastic are they ? You seem very quick to criticise, but judging by your questions, you are keen to 'score points', and not enormously well informed about some of the targets you choose.
Don't get me wrong - I don't think horizontal axis wind turbine urban wind is a good idea, and I fear that there may be a backlash against renewables as a whole if it is marketed cynically. None the less I don't know the details of who is making what claims about urban turbines - we just warn people off them in our consultancy work, decline to install them, and discourage others from doing so.
Cheers, J/. -- John Beardmore

On Sun, 19 Nov 2006 22:39:56 +0000, John Beardmore wrote:

In message , Joe Fischer joe@westpointracing.com> writes I am searching for something to convince me, right now I am looking for __THE__ current global mean temperature.
I'm sure it shouldn't be too hard to track down.

http://education.arm.gov/studyhall/globalwarming/beginwhatis.stm
Says 14 degrees (57), but

release 1982 0987 The current average global temperature is l5 (59 F). A gradual trend toward cooler climate began about l00 million years ago, resulting in the glacial ... www.jpl.nasa.gov/releases/80s/release_1982_0987.html - 8k - Cached - Similar pages

is from 1982, (page may be busy, try again), and contains wording almost identical to what I read in some of the pro posts, only the quoted temp then is a degree warmer than the first link above written after 1995.
And this second link contains this;

During most of Earth's history, the climate appears to have been considerably warmer, with average global temperatures about 25 (77 F). The current average global temperature is l5 (59 F).

in 1982.
It will take me a while to read and absorb
http://www.lenntech.com/greenhouse-effect/global-warming-discussion.htm
which I do not see anything definitive in.
And here the temperature is back to 57 degrees.
http://www.pbs4549.org/antarcti/ozone.htm
And
http://www.physicalgeography.net/fundamentals/5d.html
gives some interesting history, but I didn't see a current temperature mentioned.
And in 1993, we are back to 59 degrees in
http://www.skepticfiles.org/evolut/icecore2.htm
Just to be safe, I am going to study
http://www.solstation.com/habitable.htm http://members.fcac.org/~sol/solcom/habitable.htm
to see if a way to find another planet with the right temperature orbiting a star in the "Habitable Zone". I don't think many of us will be able to wait for the sun to brighten enough for Mars to be in the HZ.
The link
http://www.gpiatlantic.org/pdf/greenhouse/ghg.pdf
talks about the reduction of emissions in millions of tons. What doesn't seem to be discussed is the CO2 emissions of people and animals. I emit about 2 pounds of CO2 daily, and I only weight 200 pounds, so the emissions of the population of the world must be many millions of tons, and including all the animals, life forms may emit more CO2 than burning fossil fuels.
There were only about 39 hits using
http://www.google.com/search?q=%22the+current+average+global+temperature%22+&hl=en&lr=&start=20&sa=N
and I didn't try any PDF links because I am on dialup.
Joe Fischer

On Mon, raden wrote:

In message x Joe Fischer joe@westpointracing.com> writes I am searching for something to convince me, right now I am looking for __THE__ current global mean temperature.
anywhere in Septicstan would prolly do

I found 15 degrees, and danger of 2 or 3 degrees higher in the next 50 years.
Now should I start worrying about a few other possibilities, like the asteroid in 2028, or one of these
http://www.iceagenow.com/Five-Potential_Supervolcanoes.htm
and a 100 year winter?
Joe Fischer

John Beardmore wrote:

In message , 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.
No need - it was unconvincing the first time as indeed I pointed out giving at least one example of why.

your example illustrates your unfamiliarity with the concept. I'll go see if I've got the link...
http://periodpropertyshop.co.uk/phpBB2/viewtopic.php?t=6888&sid=5ca008e775816416ce3381a9440c4fc2 Relevant posts are mostly on the first few page and the last.
NT

"Joe Fischer" wrote in message

I've been told that the volcano which formed Yellowstone National Park (or is it the Grand Canyon - you know Brits, we don't know the difference) is about to blow at any time.
By a citizen of USA.
That is a super volcano, there are only a few of those in the world, and while speculative, it is something that could possibly almost obliterate the US and part of Canada.
Pray it never happens.

Oh, I shall pray :-)

"John Beardmore" wrote in message

In message , Mary Fisher mary.fisher@zetnet.co.uk> writes
Given that the only realistic saving is in hot water (an optimistic 70%), not house heating (when it's REALLY required)
I wonder what is thought of as REALLY required.
Our thermostat is set at 10C - that is, the thermostat is wound to its lowest setting. When it comes on in the night, as it did last night when we had a frost, it's too hot for us.
Turn down the boiler then ?

I've turned off the bedroom RTV.
But that doesn't answer what is REALLY required in terms of house heating. Most houses I go into seem to have the thermostat at 25C, the inhabitants wear minimal clothing.
Daft, I call it.
Mary

"David Hansen" wrote in message

On Sun, 19 Nov 2006 19:46:16 GMT someone who may be raden raden@kateda.org> wrote this:-
Today, with the outside temperature at 6C (and overcast sky) we had water at 25C. That's not hot enough for Spouse's washing up or my baths but it's fine for hand washing and it means that the boiler won't need to be on as long to raise the water temperature to his acceptable level.
So, considering it's not really cold and your system's struggling

Not really cold? You'd be happy to have your room temperature at that?

Solar water heating works on the sun, not the external temperature. The two do have some relationship, but the temperature from a solar system essentially depends on the length and intensity of the sunlight, the external temperature is largely irrelevant (except for frost protection in some systems).
not really very good then

It is very good. Even if the temperature in the cylinder needs to be boosted it will use far less gas and time than if the mains cold feed were being heated.
I'm not trying to persuade anyone to have solar water heating, I do wonder why people try to prove that our system isn't good.

Look at the subject and note that the manufacturers say that solar water heating will provide nearly all the hot water in the summer, assuming a properly sized system, but need some boosting in autumn, winter and spring, depending on the amount of sunlight. The hot water requirement does not change much with the seasons.

That's true for us. In summer we sweat so have to change clothes more frequently but in winter we wear more layers.
Mary

On Mon, 20 Nov 2006 01:28:09 +0000, John Beardmore wrote:

In message , Peter Parry peter@wpp.ltd.uk> writes
That of solar panels is, to put it mildly, rudimentary.
I don't think so. Have you actually seen any test results,

Yes, but to be fair the devices themselves are fairly simple so rudimentary testing is probably quite adequate.
As it is we do at least have some independent field testing of solar water panels done for the DTI (Side by Side testing of 8 Solar Water Heating Systems - ETSU S/P3/00275/REP/2) and the follow up which looked at the methodology used in the first test compared with ISO 9459-2.
Per panel this showed an annual energy contribution between 3,200 and 4,000 MJ (890 - 1100 kWh). Take an average of 1,000 kWh and a fuel cost of about 3p per kWh and you save about GBP30 per year per panel.
Three of the eight systems on test had failures of some sort at some point during the one years testing.

and offered a report about it if anybody is interested,
Yes please.
You have mail,

Not got it yet, if it is quite large could you please try (peter at wppltd dot demon dot co dot uk) as the mail relay has a limit of either 3 or 5M.

though as I said in it, please do not redistribute without the consent of CREST.

No problem.

Really ? I doubt most of know a cube law from a short plank ?

You are probably right :-). I'm pretty sure they know what the realistic performance of their devices in an urban environment is going to be though and don't want it mentioned under any circumstances. Wasn't there a comment recently that windmills are now B&Q's single biggest profit earner?

That's why they are so enthusiastic about using the wildly optimistic NOABL database (when used for urban wind) with no correction for surface roughness.
Just how enthusiastic are they ?

It's what they appear to be using to judge wind suitability of a site, the "on site inspection" appears to be no more than a check the house isn't actually surrounded by trees.
When I asked about one here the site was "checked on the computer" and found to be "suitable" subject to on site check of the surroundings.
The NOABL estimate for here is 4.4m/s average. However, if you include surface roughness in the calculation that drops to about 1.5m/s which isn't far from reality and wholly unsuitable for a windmill.
-- Peter Parry. http://www.wpp.ltd.uk/

On Mon, 20 Nov 2006 13:23:55 +0000 Peter Parry wrote :

As it is we do at least have some independent field testing of solar water panels done for the DTI (Side by Side testing of 8 Solar Water Heating Systems - ETSU S/P3/00275/REP/2) and the follow up which looked at the methodology used in the first test compared with ISO 9459-2.
Per panel this showed an annual energy contribution between 3,200 and 4,000 MJ (890 - 1100 kWh). Take an average of 1,000 kWh and a fuel cost of about 3p per kWh and you save about GBP30 per year per panel.
Three of the eight systems on test had failures of some sort at some point during the one years testing.

What sort of failures? One wonders what this rate might extrapolate to during the estimated payback period - progressively worse, or once the weaknesses are knocked out, long-term reliability?
-- Tony Bryer SDA UK 'Software to build on' http://www.sda.co.uk

On Mon, 20 Nov 2006 14:24:06 GMT, Tony Bryer wrote:

On Mon, 20 Nov 2006 13:23:55 +0000 Peter Parry wrote :

Three of the eight systems on test had failures of some sort at some point during the one years testing.
What sort of failures?

In total there were 6 failures, 3 on delivery and three in use.
The three on delivery were -
A defective controller PCB. (Zen) Tube in vacuum array mounted upside down (Riomay) Blocked non return valve (Filsol)
in service the three faults were:-
1. System boiled after power cut - melted manifold to supply plastic pipe, during rectification non return valve found to have no internal components. (Riomay)
2. System pump failed (Fieldway)
3. System boiled after power cut, afterwards overpressure release valve leaked. (Thermomax).
There were two vacuum tube panels (Riomay and Thermomax) and 5 flat panels.
-- Peter Parry. http://www.wpp.ltd.uk/

In message , meow2222@care2.com writes

John Beardmore wrote: In message , 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.
No need - it was unconvincing the first time as indeed I pointed out giving at least one example of why.
your example illustrates your unfamiliarity with the concept. I'll go see if I've got the link...
http://periodpropertyshop.co.uk/phpBB2/viewtopic.php?t=6888&sid=5ca008e7 75816416ce3381a9440c4fc2 Relevant posts are mostly on the first few page and the last.

Well, they certainly restate your position, but they don't answer the points I raised when this first came up in this thread, or deal with the example I gave.
No professional environmental decision maker would see this as a viable method - at best it's a poor indicator - at worst it's deeply misleading !
Cheers, J/. -- John Beardmore

In message , Peter Parry writes

On Mon, 20 Nov 2006 01:28:09 +0000, John Beardmore wookie@wookie.demon.co.uk> wrote: In message , Peter Parry peter@wpp.ltd.uk> writes
That of solar panels is, to put it mildly, rudimentary.
I don't think so. Have you actually seen any test results,
Yes, but to be fair the devices themselves are fairly simple so rudimentary testing is probably quite adequate.
As it is we do at least have some independent field testing of solar water panels done for the DTI (Side by Side testing of 8 Solar Water Heating Systems - ETSU S/P3/00275/REP/2) and the follow up which looked at the methodology used in the first test compared with ISO 9459-2.
Per panel this showed an annual energy contribution between 3,200 and 4,000 MJ (890 - 1100 kWh). Take an average of 1,000 kWh and a fuel cost of about 3p per kWh and you save about GBP30 per year per panel.
Three of the eight systems on test had failures of some sort at some point during the one years testing.

Yes, but the stuff for clear skies goes way beyond this, and covered all the approved products !
See for example
http://www.solarenergy.ch/spf.php?lang=en&fam=2&tab=3
http://www.solarenergy.ch/spf.php?lang=en&fam=21&tab=1
http://www.solarenergy.ch/spf.php?lang=en&fam=1&tab=1
http://www.solarenergy.ch/spf.php?lang=en&fam=1&tab=1
and as an example of details on the standardised tests on a specific collector
http://www.solarenergy.ch/factsheets/scf500en.pdf

and offered a report about it if anybody is interested,
Yes please.
You have mail,
Not got it yet, if it is quite large could you please try (peter at wppltd dot demon dot co dot uk) as the mail relay has a limit of either 3 or 5M.

It was 1172k encoded so should be OK, and I've had no bounce or rejection message. There yet ?

though as I said in it, please do not redistribute without the consent of CREST.
No problem.

Thanks.

Really ? I doubt most of know a cube law from a short plank ?
You are probably right :-). I'm pretty sure they know what the realistic performance of their devices in an urban environment is going to be though and don't want it mentioned under any circumstances.

:) Maybe, but maybe most of there other products are crap too ?

Wasn't there a comment recently that windmills are now B&Q's single biggest profit earner?

Somebody was saying that the had 24,000,000 worth of orders, which is certainly very depressing if true !!

That's why they are so enthusiastic about using the wildly optimistic NOABL database (when used for urban wind) with no correction for surface roughness.
Just how enthusiastic are they ?
It's what they appear to be using to judge wind suitability of a site, the "on site inspection" appears to be no more than a check the house isn't actually surrounded by trees.
When I asked about one here the site was "checked on the computer" and found to be "suitable" subject to on site check of the surroundings.
The NOABL estimate for here is 4.4m/s average. However, if you include surface roughness in the calculation that drops to about 1.5m/s which isn't far from reality and wholly unsuitable for a windmill.

Yes - were typically expecting a 1 or 2% capacity factor.
Cheers, J/. -- John Beardmore

On Sun, 19 Nov 2006 13:54:56 -0500, Joe Fischer wrote:

In the immediate future, global warming is not the scary thing, volcanic activity on the continent of Antarctica should be the most feared thing by property owners in low lying coastal areas.

I hate to break the news to you but there is volcanic activity in Antarctica. In fact Mount Erebus is classified as a stratovolcano, the same as Krakatoa and Mount St Helens and we all know what a bang they made.
Do SUV's float?
--