Self-replication, nanorobot

A photoelectrolysis hydrogen fuel energy system uses self-replicating nanorobots ( nanobots ) to mimic the first half of the photosynthesis process to produce hydrogen gas. Fuel cells made of carbon nano-tubes could be used to interface with all energy consumers. This hydrogen fuel energy system is conceptualized as shown in Fig. 7. 

Whether nanotechnology will be good or bad for the human race remains to be seen. There is tremendous potential associated with the ability to manipulate individual atoms and molecules, to deliver medications to a disease site, and to build products such as cars that are lighter yet stronger than ever. There also exists the persistent worry that humans will lose control of this technology and face what one writer called gray goo, a scenario in which self-replicating nanorobots take over and ultimately destroy the world. 

In order to manipulate the immense number of atoms required to make a product, scientists plan on constructing tiny robots called nanorobots. Nanorobots would have two objectives— to manipulate atoms and to copy themselves (self-replication). Through self-replication, countless nanorobots could be created. This work force of nanorobots would then work together to quickly and efficiently assemble new products. 

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