According to the World Nuclear Association, 30 countries world wide operate 435 nuclear power plants and create 16% of the worlds power.  This is a substantial amount of energy created with out burning coal, but is it renewable?  The truth is uranium is not renewable and at this time there is no process in use which creates synthetic uranium for power plants.  At the current cunsumption rate, the reserves of nuclar power material (uranim 235) is expected to last somewhere between 50 and 100 years. 

     Many see nuclear power as an optimal fossil to renewable transition energy.  It is not a solution for the long term and it is appearent that at some point we need to swith to an eniterly renewable energy system.  In the mean time is nuclear a safe solution?  Well… yes and no.  Nuclear waste is known to cause a wide variety of ailments from cancer to birth defects. In the defense of nuclear energy, the waste created has considerably less of an impact on our environment than buring coal. The waste that is created by nuclear power is stored in concrete containers at the plants and ultimately will be properly dumped in a remote desert area in Navada (Yucca Mountain). 

     There is a process of breeding nuclear fuel, creating plutonium, which can be used when uranium begins running thin, but this will only extend the recource and is not currently being used in any commercial application.  The bottom line is, in the short run, environmentaly, nuclear is a cleaner energy than coal, but it too will need to be replaced.