The Solar Tower

Hi Rikk,

Welcome to CR4!

This is a fascinating topic. I remember a science fiction short story about these towers, although I can't remember the author's name. He referred to them as "shortstacks." The main character's kid asks "why are they called shortstacks if they're so tall?" (The answer was that the fictional inventor's name was Short.

There is already some discussion of this topic on CR4 in the comment thread in the future energy sources blog here.

A working demonstration solar tower for steam/power generation was built and operated for a while in the early 80's at Dagget Calif, adjacent to the 'Coolwater' coal gasification power generation demonstration plant.

One major problem with all forms of 'enhanced draft' type power generation schemes is the very low pressure differential available to drive the power recovery turbines. VERY large blade areas are required to recover meaningful energy, and costly and heavy metal blades are required for the high temperatures--way hotter than composites or plastics can tolerate.

It represents a plethora of mechanical design problems that have not been solved.

Dear Sir,

Can I paraphrase John Kennedy's message on being elected President of the USA " "Dont ask what your Government can do for you, ask what you can yourself do for the Nation" Though the original exact words may not have been as quoted here, the answer is : get off your back and stop asking the Government to do things. (Yes I am Australian and dislike wingers. particularly during federal election times ! )

Reverting to the item , there is a Spannish tower in existence and from all reports it has been a sucess. In all of these forms of secondary energy the bigest problem is to be able to either : complement them , boost them , or use them intermittently only in a meaningfull and profitable way . I would imagine that the existent conversion possibility of : sea or wave- power, into vast amount of : compressed air being the easiest , and as well, being readily storable, could be used to supplement the air draft into a tower with better results for the turbines . There has been a knowledgeable answer from a contributor who clearly makes this very technical point on this issue.

I am extremely interested in this and hope that my blunt but truthfull reactions will not deter future contributions from other Australians or from any other interested contributor.

"get off your back and stop asking the Government to do things. (Yes I am Australian and dislike wingers. particularly during federal election times ! )"

Dear guest, I hope you aren't calling me a whinger?

The Australian Federal Government is supposed to be looking for ways to alleviate our dependence on coal, the highest use per capita in the world. Their solution? Nuclear power. Other technologies, some developed entirely in OZ, have been ignored for many years. The world leading solar technology has left our shores for China, pretty typical.

If you're claiming the government has no obligation to fund this research and development, then you are quite clearly wrong.

Rikk

PS: I'd just like to add, the cost to Australian taxpayers for our illegal involvement in Iraq has passed $3 billion, three times the estimated cost of this project. One is providing power for 200,000 homes, the other is killing innocent civilians and threatening world peace. If anything, it's wars this government should be keeping it's nose out of.

Rikk,

You're dam right there mate. I recall years ago a segment on tv when the power company was accused in parts of the Eastern states, mainly in New South Wales, for blocking remote farms to have their own Solar Power stations setup for @ $50,000.00 each (this was around 1990). Instead, for that amount the power company took the effort to extend their grid out there for which even the goverment later was attacked for due to some technical issues and wasting arable land.

Hi Guest. The water tower principle is in use in Western Norway since 1984. Norways western coast is subjected to huge north Atlantic rollers at all times. What they did was to place a large diameter hollow tower in the sea at a depth of 12 meters. The large column of air inside this tower produces a wind surge up and down inside the tower, at about 3/4s of the way up in the tower they placed a large 9 bladed wind turbine. It was so successful that they built three more. I know all this because I was on this project. Spencer.

According to what I read lately there is such a project for south of Spain and quite advanced.

Getting back on topic, I was involved in an exploratory project very similar to this one, except sea water was pumped to the top and sprayed in. The evaporation of the water and subsequent cooling of the air column would drive the flow downward toward the base and power "wind" turbines. The turbine blades were to be 100m in diameter, if I remember correctly. I worked for Southern California Edison at the time and was in charge of reviewing this rather large technical proposal from some folks in Israel. The document was jammed full of theory and mathematics, but it lost credibility in my eyes when, in all this detailed analysis, they had neglected to consider the pumping energy required to get the water to the top of the column! It was over 1/2 of the claimed energy produced. Never mind the fact that none of our structural engineers wanted anything to do with the tallest structure ever built (1000m tall).

I'm not going to get into an argument over what the government should or shouldn't fund. They do a fair amount of R&D funding as it is, including Geothermal power generation. Global warming is everyone's concern, and if government initiatives tread on toes, so be it. I certainly don't see the suggestion we all build a new house as being the answer!

The beauty of the tower, if it works, is that it's virtually free, clean power, after the initial outlay.

One thing I was wondering was the moisture in the air, what happens to it as it climbs the tower and cools down?

R

I found this page, it contains videos, one of which is the pilot project, built in Spain.

Solar Tower Videos

R

The problem with esoteric ideas like this as that they do not take into account the final cost per kilowatt/hour over the life of the plant.

This design is very costly to build and maintain and very inefficient in the amount of power produced for the costs involved.

Over the past 40 years I have been involved in many different pilot co-generation power plants, and a few wave power and thermal/differential generating plants. These never got much beyond the pilot plant stage because of the cost vs kw/hr factor was too low.

There are a multitude of ways to accomplish almost anything, we need to keep trying different approaches to solve the energy production problem. I am positive that a solution will be found, but this "Solar Tower" does not look like the answer at this time.

Firstly, I don't see how the running costs of this is so huge, for a start it doesn't require a constant source of fuel.

It remains to be seen if it's cost effective, especially when you factor in the "Global Warming" effect.

If we don't find a way in OZ to develop 'clean' coal, and our emissions continue to rise, the cost of Carbon Trading our way out of trouble will be immense, and technology like this will appear cheap in comparison.

"Firstly, I don't see how the running costs of this is so huge, for a start it doesn't require a constant source of fuel.

It remains to be seen if it's cost effective, especially when you factor in the "Global Warming" effect.

If we don't find a way in OZ to develop 'clean' coal, and our emissions continue to rise, the cost of Carbon Trading our way out of trouble will be immense, and technology like this will appear cheap in comparison."

Rikk, Go price a square meter of mirror that survive the elements that design must survive.

Then multiply this by how many square meters that are needed in this design.

Now think about the amount of glass cleaner needed to keep them clean and working at peak efficiently. (Not a joke. They HAVE to be clean.)

We do need an alternative to hydrocarbon based generating plants.

But solar is not it! People get sucked into the Sunlight is Free morass and common sense flies away. Wind power is good! And atomic energy is good. Solar is for dreamers. Wave power holds the most potential.

I would that you do more research in to something besides solar.

Some comments:

in the solar tower are not mirrors involved so that the clean surfaces are not required.

there are a lot of desert areas especially where the sun radiated energy is high so that it could be of interest to make them produce electrical energy.

The prototype didn't use glass, it used a UV resistant plastic sheeting.

If it were to use glass, there is Self Cleaning Glass available anyway, should cleaning be a problem.

These towers will be built, not as THE solution, but one of many.

"This is a project I have been following the progress of for a few years now, it has been held up for lack of funds, and someone to take the risk and build the thing."

According to Engadget the Spanish version is still TALK, no action.

Spanish Solar Tower

Perhaps Spain and Australia are each waiting for the other to build a Solar Tower and report the results or there are other projects of higher priority.

You may have to track the project(s) for a few more years.

The Spanish Solar Tower I refer to was built many years ago.

Go to the following link and download the "Beyond 2000" video.

Spanish Prototype Solar Tower

"The Spanish Solar Tower I refer to was built many years ago."

Must have been a proof of concept since it worked OK the next step is a full blown power plant that is the current interest.