Please note that my 10X factor is required to replace ALL of current fossil fuel energy - the generation capacity and grid as is exists today supplies only 10% of total energy consumption ( electrical + fossil ). Of this wind and solar represent and supply perhaps 1% of demand - thus to plan long term for only wind & solar is dreaming in technicolor ! These numbers are a bit of arm waving - I merely want to point out the true magnitude of the issue if we are serious.