Thu, 25 Jun 2026 02:29:07 +0100 https://www.greenbuildingforum.co.uk/newforum/ Lussumo Vanilla 1.0.3 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162821#Comment_162821 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162821#Comment_162821 Fri, 07 Dec 2012 10:19:16 +0000 jon
The idea is to form bays of segmented mirror spheres to generate high grade heat to supply turbines for day demand. Excess heat and electricity production can be sent to air fuel synthesis or compressed air storage (for night-time demand). I've put up some 3-D Google Earth concept models in the link below (great fun to play with but not easy to transfer from AutoCAD format)

http://flyingoven.blogspot.co.uk/2012/12/concept-drawings-california-array.html

The spherical idea is inexpensive and good from a land-use perspective. From the figures I got from our test prototypes (long time ago but they're on the forum somewhere), this could potentially supply the USA or Europe with its energy needs (in the future sometime). Technically, there's no dispute about whether or not it could work (largely because a variant on it is already operational at the Auroville Solar Bowl: http://solarcooking.wikia.com/wiki/Auroville_Solar_Bowl)

Can anyone see a fatal flaw with the arrangement.. a reason why it couldn't work better than the various other large scale solar projects which are being tried?]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162822#Comment_162822 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162822#Comment_162822 Fri, 07 Dec 2012 10:41:12 +0000 SteamyTea ]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162823#Comment_162823 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162823#Comment_162823 Fri, 07 Dec 2012 10:50:02 +0000 jon ]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162827#Comment_162827 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162827#Comment_162827 Fri, 07 Dec 2012 13:41:51 +0000 djh https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162832#Comment_162832 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162832#Comment_162832 Fri, 07 Dec 2012 14:25:38 +0000 jon http://en.wikipedia.org/wiki/Heliostat)

If you're thinking of heliostats, they need to be driven: Fixed to a structure which can me moved by motors so that the mirrors remain focused on the tower. This means that the support structure is relatively expensive (together with the drivers)

The mirror array on a spherical reflector is similar: It's also flat plates arranged spherically (so the formers are very simple to make and much simpler to focus than, say, a parabolic). But the big difference is that, with a spherical reflector, the mirrors never move; only the receptor or boiler moves (for instance at Auroville near the equator, it's a set of mirrors placed permanently into the structure)

The main benefit would be in reduced cost and maintenance.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162833#Comment_162833 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162833#Comment_162833 Fri, 07 Dec 2012 14:27:05 +0000 Seret https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162834#Comment_162834 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162834#Comment_162834 Fri, 07 Dec 2012 15:18:00 +0000 renewablejohn
http://www.designboom.com/technology/spherical-glass-solar-energy-generator-by-rawlemon/

You could automate the solar collection by putting a thermal oil pipe at the focal point similar to the paper used on similar light intensity meters (Old age I forget the instruments name)]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162847#Comment_162847 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162847#Comment_162847 Fri, 07 Dec 2012 17:51:23 +0000 jon
Mirrors could be made of any reflective surface that can be made flat. Because they are fixed in one unmoving position, and are easy to focus and retain, the cheapest would probably do; sprayed float glass might be an option (on larger arrays, durability would be less of a problem).

jon]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162849#Comment_162849 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162849#Comment_162849 Fri, 07 Dec 2012 18:56:20 +0000 CWatters https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162865#Comment_162865 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162865#Comment_162865 Sat, 08 Dec 2012 10:20:40 +0000 jon
Wind isn't so much of a problem because it can be tied down (and large arrays reduce the uplift component on single units)

Sand: Good point. It would need to have holes of some sort to let sand through in the flatter areas: Doesn't matter so much where the mirror plates are at a steeper angle, but it's probably better to include it as a standard detail all round.

Part of the idea with the closely spaced fixed grid would be to establish succulents (the mirror grid is fixed so it doesn't really matter if plants establish around the framing). This could help the overall carbon footprint but the real reason for doing it would be to reduce sand blast on the mirror grids.


I've noticed that the original website I did on it is now used as a reference by several renewable, solar and farming wikis, so I'm thinking of developing it more as an open source project; perhaps transferring some of the engineering data into more use-able drawings and output. That's a lot of work if there's some major flaw, so comments are much appreciated.]]> https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162946#Comment_162946 https://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=9888&Focus=162946#Comment_162946 Mon, 10 Dec 2012 08:57:23 +0000 jon
I know it's too new agey for some, but this is a review of one of the books on the Megalithic Portal, a large and well known archaeological interest site:


“The author has obviously done a lot of research, but more importantly has put in a lot of leg-work visiting the sites mentioned in the book and has actually tried the experiments using only the materials available to megalithic peoples. When someone has done (or tried to do) something, you get an added depth to the experience and this certainly comes across in Jon’s writing. Page 11 has a marvellous example, when attempting to view the exact point on the horizon where the sun rises/sets. Even on a clear day this is often impossible due to the haze, something I also know through bitter experience.”

“The one thing that makes this book a winner is the fact that it’s central theory is not a house of cards. The various parts are not all required to prove that Stonehenge was a geocentric “planetarium” (or whatever the solar equivalent is) and equally you can accept all the parts but reject the final conclusion.”

“Highly recommended to anyone with an interest in Stonehenge.”


http://www.megalithic.co.uk/article.php?sid=2146414126


I've made it available as electronic only. We figured that given the green nature of its origins, we should keep to a green format. This one has also been made as low cost as possible; I figure that if there is a link here, it could boost the idea of renewables as a serious alternative in the public mind.]]>