Sustainable Energy Without Hot Air

[Lancashire Lad]

I’ve just been browsing a site which in my opinion should be at the very top of the favourite list of anyone with a passing interest in sustainable energy strategy: - www withouthotair.com

The site basically reproduces a chapter by chapter transcript of the book “Sustainable Energy – Without Hot Air”, written by David Mackay, a physicist and professor at the University of Cambridge.

The site is a masterpiece of simplicity, and navigation to any particular chapter, page, or subject, couldn’t be easier.

Not by any means the ramblings of a “green” activist, the book has endorsements ranging from people in Greenpeace and Friends of The Earth, to energy providers, politicians, and the government’s chief scientific advisor.

The site covers the whole gamut of sustainable energy. There is no pushing of ethical/moral high ground, just factual information – by the bucketful, and backed up by all the technical facts and figures anyone could want – if you want them.

The information is presented in an everyday manner, in a style so easy to read it makes browsing a treat. You are able to just dip in and out of any section or subject, and are guaranteed to be entertained and enlightened at the same time.

Reading the synopsis (via a link at the right hand side of contents page) gives the best introduction. The linked short video is also well worth a quick viewing. And for those with a greater interest, the full book is made freely downloadable as a PDF file.

I hasten to add, I have no connection whatsoever with this gent, but I take my hat off to him. The book is a gem, which ought to be read by everyone.

Regards,
Mike.

[John D]

Have a had very brief read MIKE through (4) WIND and (10) Offshore Wind and find it ALL very interesting.
This is without doubt a very well documented and very informative piece of work

Thanks again Mike for posting more FACTUAL INFORMATION without all the HOT AIR.

John D

[Lancashire Lad]

Cheers John,

The more I read from the book, the more respect I have for this guy. - Makes an awful lot of sense.

Just found this interview with David Mackay, which gives a good insight into his point of view and reasons for writing the book: -
Leo Hickman meets the author of this year's must-read energy book | Environment | The Guardian

Regards,
Mike.

[John D]

Originally Posted by Lancashire Lad

Cheers John,

The more I read from the book, the more respect I have for this guy. - Makes an awful lot of sense.

Just found this interview with David Mackay, which gives a good insight into his point of view and reasons for writing the book: -
Leo Hickman meets the author of this year's must-read energy book | Environment | The Guardian

Regards,
Mike.

Again very interesting Mike.
I have just come across another very interesting editorial

Is it time to generate your own domestic power? | Leo Hickman | Environment | guardian.co.uk

which again puts further thoughts and opinions into this rather complex subject of 'economical and practical alternative energy sources' debate.

All very interesting but where will it end up ???

John D

[Lancashire Lad]

Originally Posted by John D

....All very interesting but where will it end up ???

I'm as much in the dark (excuse the pun!) as you are on that one John.

The article does provide food for thought. My own opinion on "home based" microgeneration at this point in time is wholly in the camp of this contributor: -

QUOTE
"The primary psychological effect is one of delusion. People are lulled into a
sense of self-satisfaction: that they are self sufficient when in fact they are
entirely reliant on subsidy; and that they are helping to save carbon when in
fact they are diverting funds away from better options that would save far
more carbon."
UNQUOTE

The last sentence of that quote being particularly noteworthy.

I've looked in depth at several options currently available, and considering purchase/installation costs, likely lifespan of equipment, outlay/predicted payback period, none of them really stack up to a genuine cost saving, (or even a true environmental benefit - when such things as the overall carbon footprint of manufacturing the equipment etc. etc. are dropped into the mix as well).

One issue with these small "home based" systems, is that there doesn't seem to be any likelyhood of significant improvements to their efficiency ratios. - You can only get so much electrical output from a small photovoltaic panel or wind generator, and whatever that might be for given size of such a setup, it won't greatly improve in the near future without some major leaps in technology. In real terms it's probably much more effective in the long run to look at better loft insulation and that sort of thing.

To me, the subsidy situation hits the nail on the head, and is effectively falsifying the true staus quo. Subsidies can indeed make what would otherwise be a non-cost effective installation, appear to be substantially cost effective. Potentially great for the individual looking for personal energy use cost savings, but not so great if/when the subsidies are removed, or from the environmental point of view.

Elsewhere in the article, the response from Jeremy Leggett, (via link in second paragraph), is somewhat typical of the disingenuous phrasiology being bandied about: -

QUOTE
"First, Monbiot gets the workability of solar wrong. He says: "The amount
of power PV panels produce at this latitude is risible, [and] they also produce
it at the wrong time." Those who buy panels, therefore, will own a mere
"fashion accessory". The companies who manufacture solar PV in the UK
have shown that putting solar panels on all available building surfaces would
generate more electricity in a year, under typical cloudy British skies, than
the entire electricity consumption of our energy-profligate nation. Some
fashion accessory."
UNQUOTE

Looks like a great argument, but look what he is really saying: - "The companies who manufacture solar PV in the UK have shown that putting solar panels on all available building surfaces...."

Yes indeed, I'm quite sure that they would provide enough electricity, if we covered every available building surface in Britain with solar panels

His later statement is a far better appriasal of what is required: -

QUOTE
"Of course, just a fraction of that area of buildings would suffice
because we would want to mix and match renewable technologies
– large and small, onshore and offshore"
UNQUOTE

This a typical example of my comment elsewhere, where I said "...the reader needs to filter out the wheat from the chaff...".

Back on the subject of Home based / Microgenerating schemes, perhaps that warrants it's own thread? - Maybe there are WAB contributors out there who have such schemes already? - I would be very interested to hear what they have to say.

Regards,
Mike.

[animartco]

Generating own power- this is one of the reasons why I am tub thumping for flat roofs. You can get an awful lot of useful equipment on a flat roof, quite apart from improving the planet's albedo, and halving the imports of timber.
Let us face it, a pitched roof is a total waste of space! Millions of square miles of wasted space.

[ForestPaul]

Originally Posted by animartco

Let us face it, a pitched roof is a total waste of space!

Until it rains. It's a lot easier to construct a long-lasting waterproof roof using sustainable materials if it is pitched rather than flat.

[animartco]

Originally Posted by ForestPaul

Until it rains. It's a lot easier to construct a long-lasting waterproof roof using sustainable materials if it is pitched rather than flat.

This is the 21st century ForestPaul

[Jim Ford]

Could someone chip in extolling the benefits of HHO please - I could do with a laugh!

Jim

[Meta menardi]

Originally Posted by Jim Ford

Could someone chip in extolling the benefits of HHO please - I could do with a laugh!

Jim

Don't Jim, you will wake the children.

[Doggle Avaddit]

Originally Posted by Jim Ford

Could someone chip in extolling the benefits of HHO please - I could do with a laugh!

Jim

That wouldn't be you shouting from the sidelines again, Jim?

[eeyore]

Originally Posted by animartco

This is the 21st century ForestPaul

indeed it is - and flat roofs are so last century

forest paul is right that a pitched roof is much more waterproof and long lasting, even with modern materials

plus if it is constructed with a a south elevation it is far more efficient for solar panels than a flat one

[STYRBJORN]

Err - how about a FLAT roof, ie in a single plane, pitched at an angle of say 15*? Excess water runs off but the roof still gains maximal sunlight. A "flat" roof need not be a "horizontal" roof.
We get trapped by language sometimes.

STYRBJORN.

[eeyore]

Originally Posted by STYRBJORN

Err - how about a FLAT roof, ie in a single plane, pitched at an angle of say 15*? Excess water runs off but the roof still gains maximal sunlight. A "flat" roof need not be a "horizontal" roof.
We get trapped by language sometimes.

STYRBJORN.

what you are describing is a monopitch roof - flat roofs are horizontal because if they aren then they arent flat to (ie parallel with) the ground. QED

[Jim Ford]

Originally Posted by eeyore

what you are describing is a monopitch roof - flat roofs are horizontal because if they aren then they arent flat to (ie parallel with) the ground. QED

[PEDANT_MODE]
I would think that 'horizontal' is better described as 'a line or plane at right angles to the local direction of the force of gravity'!
[/PEDANT_MODE]

Jim

[Lancashire Lad]

Originally Posted by STYRBJORN

Err - how about a FLAT roof, ie in a single plane, pitched at an angle of say 15*? Excess water runs off but the roof still gains maximal sunlight. A "flat" roof need not be a "horizontal" roof.
We get trapped by language sometimes.

STYRBJORN.

By that logic, every roof other than domes and the like are flat

In this instance, Animartco was patently referring to a "flat" flat roof, i.e. one which is parallel with the floor below it.

For the record, I'm with Eeyore on this. I've been around the building industry all of my working life, and lost count of the number of times I've seen water penetration problems with flat roofs.

Eeyore is correct again with regards to solar energy capture - i.e. the best typical roof structure would be one pitched at right angles to the sun's line of travel across the sky, thus enabling it to "face" the largest possible amount of direct solar radiation.

The best structure overall, would be one that followed the sun's line of travel, (i.e. maintaining itself full face on to the sun), but that is obviously not practical for anything other than purpose built solar power stations.

Regards,
Mike.

[STYRBJORN]

Well Nyaah to the pair of yez. Would you care to discuss whether the universe follows Euclidean plane geometry, Lobachevskian closed space or Gaussian open curvature?

Replies on a postcard please. A flat space Euclidean one for preference. WITH A STAMP!!!

[Lancashire Lad]

Originally Posted by STYRBJORN

Well Nyaah to the pair of yez. Would you care to discuss whether the universe follows Euclidean plane geometry, Lobachevskian closed space or Gaussian open curvature?

Replies on a postcard please. A flat space Euclidean one for preference. WITH A STAMP!!!

"The" universe? - That implies you only believe there's the one. - What about the theory of infinite numbers of unverses .

Regards,
Mike.

[STYRBJORN]

OK "the universe in which we happen to exist" If you accept the Everett-Wheeler-Deutsch model of quantum mechanics, as I do, then there are an infinite number of alternative universes but we can never contact any of them. We are still stuck with the one in which we just happen to be.

Anyway what da wot not. It's oh flux in the morning and I am listening to Maddy Prior and Steeleye Span. Bet I'm happier than you!

STYRBJORN

[Lancashire Lad]

Originally Posted by STYRBJORN

....It's oh flux in the morning and I am listening to Maddy Prior and Steeleye Span. Bet I'm happier than you!...

Mmmm - All around my hat, Hard times of old England, The ups and downs, The twelve witches, Rogues in a nation... That takes me back! - I'll have to dig the old vinyls out.

Regards,
Mike.

EDIT - Just realised I've fallen all too easily into the trap of continuing the off topic debate. (On my own thread too ). Better leave things at that in case anyone wishes to return to the original subject of the thread.

[Meta menardi]

I have to say that I have always wondered, given the problems with flat roofes, Copper Knickers invented the sun and the circulation of planets through the heart, or am I missing something (perhaps a sense of decorum)

[STYRBJORN]

Originally Posted by Meta menardi

I have to say that I have always wondered, given the problems with flat roofes, Copper Knickers invented the sun and the circulation of planets through the heart, or am I missing something (perhaps a sense of decorum)

Tut-Tut. You must learn to take life seriously. Hmm. Copper Knickers. Brass Bras? Nickel Navel studs? Top hat tail coat and a whip?
Excuse me, I need a cold shower.
STYRBJORN

[Meta menardi]

Originally Posted by STYRBJORN

Tut-Tut. You must learn to take life seriously. Hmm. Copper Knickers. Brass Bras? Nickel Navel studs? Top hat tail coat and a whip?
Excuse me, I need a cold shower.
STYRBJORN

Come back to the subject, I was mis-understood, your Honour.

[STYRBJORN]

A friend of mine designed a hot air driven generator for his Master's in Environmental Engineering. It would only work in desert conditions but it would be far more efficient than photo-voltaic panels.

Imagine a 250m high chimney. Surrounding the base is a glass topped structure 1km in diameter, shaped rather like an inverted saucer with its lip raised clear of the ground. The air in the "saucer" is heated by sunlight, moves up rowards the centre, and flows up the chimney. As it does so, it turns fans which drive generators . . .

According to Chris's figures the velocity of the airflow up the chimney would stabilise at C150kph. A wind turbine designer would sell his wife and daughters into slavery in exchange for a guaranteed wind speed of 150kph 15 hours a day every day. The last I heard, Chris was looking at having fans around the lip of the saucer as well! Talk about greedy.

STYRBJORN

[animartco]

Hi Styrbjorn,
To be pedantic,(Aren't I always!) flat means parallel to the plane of the earth, but yes a slight monopitch could stull be tiled or whatever and ony necessitate cutting down, less than half as much rainforest- not much more than with a totally flat roof. But any pitch means there isn't a lot you can do ON the roof. It's still wasted space.
Of course the reason we are building steep pitched roofs is because we can buy four bed' houses and turn them into six, although why any sane family would want a six bed house is beyond me.