A new parabolic trough can stop global warming. Quickly.

System

No I don't mean current huge parabolic troughs in those desert solar power plants. They are too expensive to compete with coal, and too big to be put into everyone's home.

It is a new design. This time, it is cheap enough to bring solar energy cost down to well below that of any fossil fuel, simple enough to be home made using basic hand tools, small enough to sit on rooftops, while powerful enough for efficient electricity generation.

Visit http://wims.unice.fr/xiao/solar/index.html

It reminds me of the old days when personal computers began. At that time, there were big computers, too expensive for ordinary people, too big for homes. Then some smart people started building cheap and small computers in their garages, called "personal computers".

Today, these people are big bosses of some top IT companies. I let you name them.

If you want to repeat the history, let me help you.

Windsun

Re: A new parabolic trough can stop global warming. Quickly.

Assuming that you buy into the global warming theory, not everyone does.

Aside from that, not sure what you do with this trough once you build it. Without some sort of tracking to follow the sun, it is not going to be very efficient.

I see other problems with it also, but will leave that for others to comment on.

System2

Re: A new parabolic trough can stop global warming. Quickly.

Windsun wrote: »

Aside from that, not sure what you do with this trough once you build it. Without some sort of tracking to follow the sun, it is not going to be very efficient.

The picture shows a working system with tracker and pump. It is not as naive as you used to see.

And it is ready for heat and electricity cogeneration.

System2

Re: A new parabolic trough can stop global warming. Quickly.

It does not bother me that you put my post in the "skeptics" column. In fact, if someone says that he believes me at this stage, it is me who will doubt his sincerity.

But I do want people to try it. Technical details are released, so that it can be built by people with minimal do-it-yourself skill. Right to a complete system.

You won't be taking a big risk by doing so. Except maybe a bit of your time. If it comes out to be true, you are a pioneer. I am not here to cheat anybody, because you can do it without paying me anything.

Of course, if you are here to look for something ready to buy, it is not the time for you. Come back 2 years later, maybe.

This document gives you step by step instructions on how to build one: http://wims.unice.fr/xiao/solar/diy-en.pdf

When somebody comes out with something, please tell us your result.

If you have questions, doubts, objections etc., post them here and I will explain.

Cariboocoot

Re: A new parabolic trough can stop global warming. Quickly.

Nothing can stop global warming except complete elimination of all energy use:
Every bit we use of whatever type eventually becomes infra-red (heat) regardless of what it started out as.

Conservation is more important than finding new sources of energy to waste.

BB.

Re: A new parabolic trough can stop global warming. Quickly.

One of Azuedu links was to the STG project.

Using car parts (power steering pump and turbo charger connected to an alternator) to run off a butane or pentane boiler "fueled" by the parabolic reflector.

Interesting as a back yard mechanic exercise. But, I really wonder that it would go anywhere (I found these guys a year or so ago--and they seem not to be moving too fast). Hard to tell if the website is more hype than real to collect donations and build up a resume for college students (not enough information to see how the system was really built).

Notice that in any remote and poor location, security is a huge problem... Their one (of two?) demonstration systems had the storage batteries stolen.

Wonder why they are working in Africa instead of spending the costs of the trip building and debugging the systems "at home" first.

-Bill

System2

Re: A new parabolic trough can stop global warming. Quickly.

Cariboocoot wrote: »

Nothing can stop global warming except complete elimination of all energy use:
Every bit we use of whatever type eventually becomes infra-red (heat) regardless of what it started out as.

Solar energy comes to the earth, and becomes infra-red, whether you use it or not. So exploiting solar energy directly does not add to infra-red on earth.

System2

Re: A new parabolic trough can stop global warming. Quickly.

BB. wrote: »

Interesting as a back yard mechanic exercise. But, I really wonder that it would go anywhere (I found these guys a year or so ago--and they seem not to be moving too fast).

Glad to hear from people with inside information. I don't know these guys. I put the link in because I cannot find better for the time being.

Home turbine will be an important problem. Because thermoelectric devices are too inefficient, and tellurium ressources are rare. People keep telling me that this one is hard, and maintenance will be a trouble. I don't know; cars should be much more complicated than that.

BB.

Re: A new parabolic trough can stop global warming. Quickly.

Technically, that answer is not 100% correct. The albedo of a solar collector (thermal or PV) is lower than the average earth itself (soil, vegetation, etc.). So, overall, they collect more energy and keep it at the ground level vs reflected energy from the earth back to space.

So you can could localized heating effects from very large installations. The simple act of collecting electricity and shipping it off to far away areas, can affect the total albedo of the local site.

-Bill

System2

Re: A new parabolic trough can stop global warming. Quickly.

BB. wrote: »

The albedo of a solar collector (thermal or PV) is lower than the average earth itself (soil, vegetation, etc.). So, overall, they collect more energy and keep it at the ground level vs reflected energy from the earth back to space.

So you can could localized heating effects from very large installations. The simple act of collecting electricity and shipping it off to far away areas, can affect the total albedo of the local site.

-Bill

More exactly, globally you have to compare the effect of eventual solar collectors with that of co2. I haven't done the exercise, but I think that co2 should be much more important.

Locally, this is more subtle. Fortunately, this collector can now be used in a distributed manner, local generation.

mike95490

Re: A new parabolic trough can stop global warming. Quickly.

1) your parabolic trough looks like a cylinder. They are not the same shape.

2) " Concentration ratio 40-100 " Welll, that makes planning a bit difficult.

BB.

Re: A new parabolic trough can stop global warming. Quickly.

Well, for us AGM deniers, CO2 has minimal effect on surface temperatures. The major green house gas (or at least IR moderating gas) is Water Vapor. And we know that clouds have a huge effect... I don't go looking at my CO2 meter to see if it is going to be hot or cold tomorrow, I look at the forecast regarding cloud cover. And even then, it is much more complex because clouds transport a huge amount of heat, and they reflect short and long wave IR heat back into space from the sun, and long wave IR back down to earth.

Just like adding insulation to an enclosed box does not make it warmer--it just limits the temperature extremes (assuming no other heat sources or sinks) inside the box. Now, we can guess that the colder temperatures are not as cold, and the hotter temperatures are not as hot--did the "average" temperature go up or down?

Even a 100 years ago, it was proven that the "real green house effect" was not the result of glass letting in short wave IR and trapping/reflecting long wave IR. It is not... The Green House Effect (see last section of linked post) is based on preventing convective and wind mixing of ground "heat" and warm air with upper level cooler air. Any material that trapped wind and convective currents inside would do the same thing.

At this point, we already see what buildings (blocking wind flow) and adding additional heat (electricity and fossil fuels) does to cities--it is called the urban heat island effect.

So--if you are wondering, it is not hard to figure out the albedo of a solar panel / solar collector... But, to a degree, it also depends on where you install them... Put them over an asphalt roof, dirt, or paved area--the panels will probably reflect more heat than the roof, dirt, or paving. If you put them over sand, green vegetation, etc., they probably will absorb more heat.

Is it more or less than burning fossil fuels--don't know.

And by adding solar panels could act like a "real" green house and prevent mixing of air which will affect the local environment.

In any case, any change, whether by humans or nature, will have lots of effects (large and small). I don't believe that all life on earth will end if we put in several thousand square miles of solar panels--but there will be secondary effects (from the panels themselves, the mines for the source of the solar panels and structure, human use of power, etc.).

If people using these collectors can limit the burning of fire wood and other sources of heat (dung, brush, etc.)--it will probably have a positive effect on the local environment and reduction of desertification.

-Bill

System2

Re: A new parabolic trough can stop global warming. Quickly.

mike90045 wrote: »

1) your parabolic trough looks like a cylinder. They are not the same shape.

That's probably because you are used to see troughs with a different rim angle. Often they are of smaller rim angles. But parabolic cylinders can have different rim angles (opening angles).

mike90045 wrote: »

2) " Concentration ratio 40-100 " Welll, that makes planning a bit difficult.

You don't have to. The concentration ratio is interchangeable: the box is always the same, and you can change the concentration ratio by replacing the receiver.

http://wims.unice.fr/xiao/solar/index.html