Sci-fi fans will tell you that it's not hard to picture scenes from the far future. We have fleets of interplanetary ships exploring the vastness of space, which is hard to understand. We have a lot of hardy settlers who are changing the way strange new worlds look. 

There is a long chain of people made of will, knowledge, and intelligence that goes all the way across the Milky Way and far beyond. At least, that's one way to look at it. Some people would talk about a violent, military future for humans or a future with formless consciousnesses and connections of artificial intelligence that cover the whole planet. 

But in all of them, there is one thing people can't live without energy.

Energy is such an essential and vital part of civilization, whether it exists off-world or not, that Soviet astronomer Nikolai Kardashev classified spacefaring civilizations in 1964 according to how much energy they used; the higher the rating, the more developed, as stated by Space.com. 

We're talking about a lot more than simple fuels like coal and oil. Because humans haven't fully utilised the energy present on our own planet, Earth isn't even a Type I civilization. A Type II civilisation, on the other hand, might be able to construct a Dyson sphere-like energy-harvesting device around its own sun, according to Popular Mechanics. 

After all, just like they need resources, all those intergalactic spacecraft, stations, communities, etc., require power from somewhere.

What if the cosmos was powered by some nearly unlimited, nearly miraculous source of energy? What if it could be tapped whenever, anywhere, and from any location? That's a brief summary of zero-point energy.

Even though there is something called zero-point energy, all energy originates from the same source of inefficient systems. The sun burns hydrogen to make heat and light, just like a car burns gasoline to make heat, pollution, and other things. Both have more energy than systems that have less energy. 

As sites like Study.com and ThoughtCo explain, energy is transmitted from the high system to the low system because energy always seeks disorder, or 'entropy.' Alternatively, if your hand and the sun were the same temperatures, the sun wouldn't feel warmer because there wouldn't be a difference in energy, which is what makes heat.

Forbes says that we are living in a period of high physical order, which is why we have things like frothing balls of nuclear combustion stars spinning around in space, pistons moving upwards and downwards in a car engine, flammable wood catching fire to make bonfires, and so on. 

That is, cosmologically speaking, from the Big Bang to the Heat Death of the universe, 13.8 billion years after the Big Bang, we live in a time when the universe is full of many separate, discrete systems that use and make energy. 

But Big Think says that when the universe reaches 'heat death,' when all energy is perfectly even and smooth, there won't be any heat or light due to the lack of energy differences anywhere. 

That is the most chaotic time. What now? ThoughtCo says that now is a unique moment with 'free energy.'