As a cynical optimist, I've a feeling that not only will our civilization be around a lot longer than most people think, but that we are still in the dawn time for our species. That's pretty optimistic, given that, depending on how liberal you are with the definition of what "human" is, our species has been around for a quarter million years or so.
However, the cynical part means far future people are going to make serious fun of us primitive, paranoid early humans. Case in point: energy production. There will come a day when far future people will make the statement: "Can you believe those assholes burned oil?!!!?!!!"
Instead, of, you know, using it to manufacture youth butter, the stuff that keeps us all looking immortal and ageless.
But, energy production. I think we just might be entering the era where we go beyond the primitive 19th century techniques we've used so far: burning shit to heat water up to make steam. Wow. Fucking cave people.
Your Government (US citizens) has some programs funded through Arpa-E that, in the unlikely event that any of them prove fruitful, would be major game changers. (See, this is why the government should NOT be run like a business, which is what so many butthead conservatives think is a good idea. It is, in fact, a completely fucking stupid fucking wet little turd of an idea, since the purpose of running a business is to make money, and if a business can get away with offering you a shitty, fucked up, shoddy product or service and you, the consumer are dumb enough to buy it, then everything is just fine. If, on the other had, we run it like a government, which has more public accountability and is thus held to higher standards...).
Scientific American has identified seven government funded programs here. (Sorry, link is for subscribers). I particularly like the syngas (petrochemical precursors) production using sunlight, water, carbon dioxide and rust. Another innovation which I like is the quantum dot solar cell. This really pushes the efficiencies of solar cells to a point that solar generation is well below the cost thresholds that fossil fuels enjoy.
In fact, when it comes to solar, the prospects are just starting to open up. Certainly within the next decade, production costs and efficiencies will be easily competitive with all other energy production schemes, especially fossil fuels. More importantly, as can be read in the previous link, solar manufacturers built, shipped out, and installed 17 nuclear power plants (17 gigawatts @ 1 plant per gigawatt) worth of generating equipment in 2010 alone. How long does it take to get a nuke plant built, let alone licensed?
But hey, speaking of nukes, there's a fun possibility that you might see small nuke plants being built. Ones that can't melt down. Ones that don't generate toxic wastes, or rather, just a tiny fraction of waste that the current monsters produce. Japan and Germany are considering dropping nuclear power generation entirely. If this thorium reactor design comes to fruition, they may want to rethink their policy.
This pint-sized thorium reactor, which uses a particle accelerator to power the reaction, could be just the thing we need.
And, of course, there's always fusion. The joke is fusion is always just thirty years away. Always. But, who knows, some schemes may work out that don't require megatons of equipment, and billions of dollars to build. (MY bet is that a fusion rocket is easier to build than a fusion power plant, and perhaps, in combination with advanced magnetohydrodynamic studies, that's the way fusion power will materialize. In space.)
In any case, I'm cynically optimistic about the prospects. Technologists area little overdue at pulling something out of their collective ass.
It may be an extremely large rabbit that pops out.