Sulphur into the stratosphere

It's well worth considering releasing dust particles in the air to reflect some of the sunlight, as an alternative to positioning mirrors in orbit above Earth. [There are] a few problems with the dust-particles approach, such as difficulties in regulating the right amount of dust. It may turn out that - in hindsight - too many dust-particles have been released in the atmosphere and that it will be quite a problem getting them out again. Another problem is that the dust-particles method will affect the climate everywhere on earth.
Sam Carana - Vital Signs 2005- Vital Facts - May 20 2005

One such proposal is by Paul Crutzen, who won the Nobel Prize for chemistry when he discovered the causes of the hole in the ozone layer. Paul proposes to shoot hundreds of rockets loaded with tons of sulphur into the stratosphere to create a vast, but very thin sunscreen of sulphur around the earth. The proposal was discussed in the BBC documentary:
Five Ways To Save The World

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Artificial Trees

Klaus Lackner, physicist at Columbia University, has proposed artificial trees to suck carbon out of the air. The trees suck in carbon dioxide for storage under the ocean-floor in disused oil or gas fields.

Such trees could be planted anywhere. A small one could sit like a TV on the lawn to balance out the CO2 emitted by one person or family. A large tree, the size of a barn, could sit in the open air, near repositories for easy transportation and storage of carbon. Klaus Lackner estimates that some 250,000 such trees worldwide would be needed to soak up the CO2 produced by human activity annually.
BBC News, 21 February 2003
Earth Institute at Columbia University
Amazon.com News

More recently, Klaus Lackner's trees featured prominently in the BBC documentary
Five Ways To Save The World

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Mirrors in Space

The concept Mirrors in Space was discussed in an article from the summer 2001 Whole Earth Review, Mirrors & Smoke: Ameliorating Climate Change with Giant Solar Sails,
by Kenneth I. Roy, PE and Robert Kennedy, PE.

Over the years, the concept has been discussed in many posts, including in the geo-engineering group by Sam Carana

The ABC show, Good Morning America, on January 29, 2007, featured a clip on mirrors in space, featuring a proposal by Roger Angel, University of Arizona, to send many small discs into space to form giant mirrors deflecting some of the sunlight from Earth.



Roger Angel's research into the feasibility of cooling the Earth with a cloud of small spacecraft near the inner Lagrange point (L1) has been discussed at:
National Academy of Sciences
National Institues of Health
Sciencenews.org
Roland Piquepaille

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$25 million prize to combat global warming

In February 2007, airline tycoon Richard Branson announced a $25 million prize for the most innovative solution to get greenhouse gases out of the atmosphere in the battle against global warming.

Former Vice President Al Gore and Virgin CEO Richard Branson talk with Harry Smith about the prize in the interview below.

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Wave Power

Thirty years ago, Stephen Salter designed a floating canister that captured wave power by driving a generator from the motion of bobbing up and down on the waves.

Since that time, a lot of water has flowed under the bridge and many prototypes have been made.

Four students at University of British Columbia worked for four months on a prototype that makes 15 Watts of energy in 10 inch high waves.


Here's a video called Taming the waves, about a project in Cornwall (UK)


Another video shows a device by Solarist


This video by SwellFuell shows a device coined Pandorra's box that uses a flywheel to get a more continuous flow of electricity.


And here's another one:

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Turbines inside a huge Solar Tower

Last year, Australian power company EnviroMission proposed the Solar Tower project - a $225 million green power experiment to construct a 1,600 foot tower with enough generating capacity to fuel 100,000 homes.

Instead of relying on solar cells, the tower acts like a giant greenhouse. The sun's energy is harnessed to create warm air currents that will drive a series of power generating turbines inside the tower. Located under the glaring sun of the Australian outback, the 50 megawatt pilot project will stand taller than Chicago's Sears Tower and sit 260 feet in diameter at the base. The capacity for the technology is far greater though, and has gained the attention of Chinese investors. In 2002, Xiang Jiang Industrial became EnviroMission's second largest shareholder and plans to build a 200 megawatt tower in Shanghai, China.

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