Energy Matters Forums

[taikura]

I am interested to know if anyone has heard anything about this proposed development.

The article:
http://www.smartplanet.com/blog/intelligent-energy/video-worlds-tallest-building-could-be-a-247-australian-solar-chimney/12558?tag=nl.e660

Company website:
http://hyperionenergy.com.au/

[Tracker]

..
yet another of these "Green Projects".. I wonder how much of the cost will come from Govt. Subsidies.

We were talking about these devices some time ago, and I recall suggesting that it might exceed my neighbour's tolerance should one appear here..

What ever happened to all the WAVE-Action generators that folk have proposed..
..
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[taikura]

Another Australian company, EnviroMission (listed on the ASX), has plans to build a similar tower in Arizona. It has reached an agreement to supply power and on 12 January 2012 announced that it has obtained finance for the entire project subject to due diligence. Enviromission's CEO said in a video interview that the project will cost approximately $750 million with potential recovery of the cost of capital in 11 years.

http://www.enviromission.com.au/

[Tracker]

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BTW - How can it be 24/7 ?

Surely it can ONLY work when the sun is available to heat the stack...
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[Gordon-Loomberah]

I haven't looked at the link, but thermal mass is one way- heat it up when the sun shines, and when the air cools down at night you still have a large temperature difference, so the convection is going to stay strong for a while. It's a good application for phase change materials. With the right absorption surface, it would be easy to get well over 100C, and with say an air temp of 20C at night, so you could still have an 80C temperature differential = good strong convection.

[taikura]

This Wiki article outlines the technology and some prototypes and proposed developments.

http://en.wikipedia.org/wiki/Solar_updr ... e_in_Spain

My basic understanding is that it relies on the relative difference in air temperature between ground level (underneath the canopy) and the top of the chimney (i.e. convection).

I would love to see an analysis of the likely cost of energy produced by such projects.

.
BTW - How can it be 24/7 ?

In theory, heat generated during the day may be stored (in the ground or by other means) and released at night.

[taikura]

According to this article, China has already built one such tower:

"Starting operation on Dec. 10, the 200-kilowatt power generating unit can supply 400,000 kwh of electricity per year, saving the equivalent of 100 tonnes of coal and 900 tonnes of water, compared with thermal power generation."

Source: http://news.xinhuanet.com/english2010/c ... 666710.htm

However, I cannot find any photographs or articles in Western media.

[Tracker]

In theory, heat generated during the day may be stored (in the ground or by other means) and released at night.

I would have thought that the idea was to REFLECT heat from the ground=plane.. Some of which would hit the tower. I would have thought that the idea was to keep the ground as cool as possible...
ie.. Heat in the ground (alone) would surely not create much convection.

The ONLY way that I could see it working 24/7, would be if there was a heat-storage device (Phase-Change???) in the outer layer of the tube, as Gordon has suggested.. but I still wonder how effective it would be, as the storred heat would be lost to the air from both the inner and the outer faces of the stack..

I'm not arguing.. I'm just curious..

PS -- Look at the first image of the device.. Sunlight is irradiating ALL the ground-plane..
WHY - Is the OUTER ends of the air-pipes, COLDER than in the centre.. ( Unless they are deeply burried and rise to near the surface at the Stack..
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[zzsstt]

I sometimes wonder how many of these projects are really ever intended to be built. There is so much money to be made in the planning stages....

It costs very little to come up with a fabulous concept that can be made to look good on paper. Then find a small number of investors, who can be easily persuaded by a glossy "concept outline" that there is a fortune to be made, and the money starts coming in. Obviously money must be spent on employing a team of experts ("mates") to carry out a feasibility study, then we have to design a proposal, wine and dine various other potential supporters etc. and such a process can take years, all the while the "project team" are paying themselves and employing ad agencies etc.

I'd be willing to bet that if you totted up the money wasted on proposed systems that never went anywhere (wave power proposals, schemes abandoned due to "lack of government help" etc.) there'd be enough money to equip half the planet with PV systems!