Nice article from Business Insider Australia on how much energy the sun generates. The author's conclusion for the US is that they just aren't capturing much of this energy. We're not capturing enough here either, but until every business in Australia has solar on the roof, it won't be --but the viability of solar is beyond doubt now. Here's an excerpt:
There’s one simple fact that may just change your thoughts on renewable power.
In a single hour, the amount of power from the sun that strikes the Earth is more than the entire world consumes in an year.
To put that in numbers, from the US Department of Energy:
Each hour 430 quintillion Joules of energy from the sun hits the Earth. That’s 430 with 18 zeroes after it!
In comparison, the total amount of energy that all humans use in a year is 410 quintillion Joules.
For context, the average American home used 39 billion Joules of electricity in 2013.
Clearly, we have a source of virtually unlimited (the sun won’t die out for another five billion years or so) clean energy in the form of solar power — we’re just not capturing it.