Is Solar Energy Inexhaustible?

Not technically, because the sun itself is exhaustible. These days, it also takes a lot of energy to collect and store solar energy. So if you are stuck with a couple of rainy days, the energy depletes itself rather rapidly. But as an overall speculation... Will you be able to get it more often than not? Yes. Will the sun ever peter out in our lifetime? No. So it is more inexhaustible than most other forms of energy.