Using the efficiency of solar panels available today and the current energy needs of the world you could produce enough power with an area the size of Arizona.

Using the efficiency of solar panels available today and the current energy needs of the world you could produce enough power with an area the size of Arizona. Assuming you ignore losses from distribution, storage etc. If you did the calculations say 30 years ago when solar was orders of magnitude less efficient you might have gotten to those numbers, but today we are in a very different situation. Nuclear base load with solar and wind will absolutely provide the vast majority of clean energy for future generations.