Planet Earth and environment
Sahara desert - before the great 21st century greening project
After the greening project
The Sahara desert is an untapped resource in two chief respects:
1. It receives a vast amount of solar energy from the sun, much of which at present simply heats the desert and the air above it. It would be better to convert this energy to electricity and food.
2. If the Sahara and other deserts (Australia etc) could be made to bloom, it would remove sizeable amounts of carbon dioxide from the atmosphere through creation of new carbon sinks.
So what, you may wonder, is running through those pipes (shown blue) that has produced the miraculous greening of the desert ?
Water, from desalination plants ? No, water is heavy, needing too much energy to pump long distances.
In fact the pipes contain hydrogen gas, produced by solar-powered electrolysis plants sited along the shoreline of the Atlantic and Mediterranean oceans.
The hydrogen is piped inland, where it is burned (at nightime) to produce electricity and pure water. Electricity is produced during the day from solar arrays.
The water that collects overnight is then used to create a patchwork of small desert oases, being suitable for both crop irrigation and for drinking.
Feasible ? The science is I believe OK, but there are some formidable technological problems still to be overcome. I'll be discussing these in future posts. In the meantime, I'll be scouring the internet for possible solutions, and maybe register with some specialist online discussion groups, such as those hosted by Digg etc.
Economics ? The threat of global warming and climate change means that old schemes, previously dropped for requiring too big an initial capital outlay, can now be dusted off and looked at afresh. That is dependent, needless to say, on being able to produce convincing evidence that such schemes can slow or counter the effects of man-made climate change through excessive burning of fossil fuels.
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